The invention relates to improved catheters, and is particularly apt to catheters for imaging and/or interventional device delivery at desired locations in the body of a patient.
Catheters are tubular medical devices that may be inserted into a body vessel, cavity or duct, and manipulated utilizing a portion that extends out of the body. Typically, catheters are relatively thin and flexible to facilitate advancement/retraction along non-linear paths. Catheters may be employed for a wide variety of purposes, including the internal bodily positioning of diagnostic and/or therapeutic devices. For example, catheters may be employed to position internal imaging devices, deploy implantable devices (e.g., stents, stent grafts, vena cava filters), and/or deliver energy (e.g., ablation catheters).
In this regard, use of ultrasonic imaging techniques to obtain visible images of structures is increasingly common, particularly in medical applications. Broadly stated, an ultrasonic transducer, typically comprising a number of individually actuated piezoelectric elements, is provided with suitable drive signals such that a pulse of ultrasonic energy travels into the body of the patient. The ultrasonic energy is reflected at interfaces between structures of varying acoustic impedance. The same or a different transducer detects the receipt of the return energy and provides a corresponding output signal. This signal can be processed in a known manner to yield an image, visible on a display screen, of the interfaces between the structures and hence of the structures themselves.
Numerous prior art patents discuss the use of ultrasonic imaging in combination with specialized surgical equipment in order to perform very precise surgical procedures. For example, a number of patents show use of ultrasonic techniques for guiding a “biopsy gun”, i.e., an instrument for taking a tissue sample from a particular area for pathological examination, for example, to determine whether a particular structure is a malignant tumor or the like. Similarly, other prior art patents discuss use of ultrasonic imaging techniques to assist in other delicate operations, e.g., removal of viable eggs for in vitro fertilization, and for related purposes.
In the past few decades, there have been significant breakthroughs in the development and application of interventional medical devices including inferior vena cava filters, vascular stents, aortic aneurysm stent grafts, vascular occluders, cardiac occluders, prosthetic cardiac valves, and catheter and needle delivery of radio frequency ablation. However, imaging modalities have not kept pace as these procedures are typically performed under fluoroscopic guidance and make use of X-ray contrast agents. Fluoroscopy has draw backs including its inability to image soft tissues and the inherent radiation exposure for both the patient and the clinician. Furthermore, conventional fluoroscopic imaging provides only a planar two dimensional (2D) view.
Intracardiac Echocardiography (ICE) catheters have become the preferred imaging modality for use in structural heart intervention because they provide high resolution 2D ultrasound images of the soft tissue structure of the heart. Additionally, ICE imaging does not contribute ionizing radiation to the procedure. ICE catheters can be used by the interventional cardiologist and staff within the context of their normal procedural flow and without the addition of other hospital staff. Current ICE catheter technology does have limitations though. The conventional ICE catheters are limited to generating only 2D images. Furthermore, the clinician must steer and reposition the catheter in order to capture multiple image planes within the anatomy. The catheter manipulation needed to obtain specific 2D image planes requires that a user spend a significant amount of time becoming facile with the catheter steering mechanisms.
Visualizing the three dimensional (3D) architecture of the heart, for example, on a real-time basis during intervention is highly desirable from a clinical perspective as it facilitates more complex procedures such as left atrial appendage occlusion, mitral valve repair, and ablation for atrial fibrillation. 3D imaging also allows the clinician to fully determine the relative position of structures. This capability is of particular import in cases of structural abnormalities in the heart where typical anatomy is not present. Two dimensional transducer arrays provide a means to generate 3D images, but currently available 2D arrays require a high number of elements in order to provide sufficient aperture size and corresponding image resolution. This high element count results in a 2D transducer that is prohibitive with respect to clinically acceptable catheter profiles.
The Philips iE33 echocardiography system running the new 3D transesophageal (TEE) probe (available from Philips Healthcare, Andover, Mass., USA) represents the first commercially-available real-time 3D (four dimensional (4D)) TEE ultrasound imaging device. This system provides the clinician with the 4D imaging capabilities needed for more complex interventions, but there are several significant disadvantages associated with this system. Due to the large size of the TEE probe (50 mm circumference and 16.6 mm width), patients need to be anesthetized or heavily sedated prior to probe introduction (G. Hamilton Baker, MD et al., Usefulness of Live Three-Dimensional Transesophageal Echocardiography in a Congenital Heart Disease Center, Am J Cardiol 2009; 103: 1025-1028). This requires that an anesthesiologist be present to induce and monitor the patient on anesthesia. In addition any hemodynamic information relevant to the procedure must be gathered prior to the induction of general anesthesia due to the effects of anesthetic on the hemodynamic status of the patient. Furthermore, minor and major complications from TEE probe use do occur including complications ranging from sore throat to esophageal perforation. The complexity of the Phillips TEE system and probe require the participation of additional staff such as an anesthesiologist, echocardiographer and ultrasound technician. This increases procedure time and cost.
Interventional clinicians desire an imaging system that is catheter-based and small enough for percutaneous access with three dimensional imaging in real-time (4D) capabilities. Rather than steering the catheter within the anatomy to capture various views, as is the case with conventional ICE catheters, it is desirable that such a catheter system be capable of obtaining multiple image planes or volumes from a single, stable catheter position within the anatomy. A catheter that would allow the clinician to guide or steer the catheter to a position within the heart, vasculature, or other body cavities, lock the catheter in a stable position, and yet still allow the selection of a range of image planes or volumes within the anatomy would facilitate more complex procedures. Due to the size constraints of some anatomical locations, e.g., that in the heart, it is desirable that the viewing angles necessary be obtainable within a small anatomical volume of for example less than about 3 cm.
As internal diagnostic and therapeutic procedures continue to evolve, the desirability of enhanced procedure imaging via compact and maneuverable catheters has been recognized. More particularly, the present inventors have recognized the desirability of providing catheter features that facilitate selective positioning and control of componentry located at a distal end of a catheter, while maintaining a relatively small profile, thereby yielding enhanced functionality for various clinical applications.
The present invention relates to improved catheter designs. For purposes hereof, a catheter is defined as a device which is capable of being inserted into a body vessel, cavity or duct, wherein at least a portion of the catheter extends out of the body and the catheter is capable of being manipulated and/or removed from the body by manipulating/pulling on the portion of the catheter extending out of the body. Embodiments of catheters disclosed herein may include a catheter body. A catheter body may, for example, include an outer tubular body, an inner tubular body, a catheter shaft, or any combination thereof. Catheter bodies disclosed herein may or may not include a lumen. Such lumens may be conveyance lumens for the conveyance of a device and/or material. For example, such lumens may be used for the delivery of an interventional device, the delivery of a diagnostic device, the implantation and/or retrieval of an object, the delivery of drugs, or any combination thereof.
Embodiments of catheters designs disclosed herein may include a deflectable member. The deflectable member may be disposed at a distal end of a catheter body and may be operable to deflect relative to the catheter body. “Deflectable” is defined as the ability to move a member interconnected to the catheter body, or a portion of the catheter body, away from the longitudinal axis of the catheter body, preferably such that the member or portion of the catheter body is fully or partially forward-facing. Deflectable may also include the ability to move the member, or the portion of the catheter body, away from the longitudinal axis of the catheter body, preferably such that the member or portion of the catheter body is fully or partially rearward-facing. Deflectable may include the ability to move the member away from the longitudinal axis of the catheter body at a distal end of the catheter body. For example, a deflectable member may be operable to be deflected plus or minus 180 degrees from a position where the deflectable member is aligned with a distal end of the catheter body (e.g., where the deflectable member is disposed distal to the distal end of the catheter body). In another example, a deflectable member may be deflectable such that a distal port of a conveyance lumen of the catheter body may be opened. The deflectable member may be operable to move relative to the catheter body along a predetermined path that is defined by the structure of the interconnection between the deflectable member and catheter body. For example, the deflectable member and catheter body may each be directly connected to a hinge (e.g., the deflectable member and catheter body may each be in contact with and/or fixed to the hinge) disposed between the deflectable member and catheter body, and the hinge may determine the predetermined path of movement that the deflectable member may move through relative to the catheter body. The deflectable member may be selectively deflectable relative to the catheter body to facilitate operation of componentry comprising the deflectable member.
The deflectable member may include a motor for selective driven movement of a component or components within the deflectable member. The motor may be any device or mechanism that creates motion that may be used for the aforementioned selective driven movement.
The selectively driven component or components may, for example, include a diagnostic device (e.g., an imaging device), a therapeutic device, or any combination thereof. For example, the selectively driven component may be a transducer array such as an ultrasound transducer array that may be used for imaging. Further, the ultrasound transducer array may, for example, be a one dimensional array, one and a half dimensional array, or a two dimensional array. In additional examples, the selectively driven component may be an ablation device such as a Radio Frequency (RF) ablation applicator or a high frequency ultrasonic (HIFU) ablation applicator.
As used herein, “imaging” may include ultrasonic imaging, be it one dimensional, two dimensional, three dimensional, or real-time three dimensional imaging (4D). Two dimensional images may be generated by one dimensional transducer arrays (e.g., linear arrays or arrays having a single row of elements). Three dimensional images may be produced by two dimensional arrays (e.g., those arrays with elements arranged in an n by n planar configuration) or by mechanically reciprocated, one dimensional transducer arrays. The term “imaging” also includes optical imaging, tomography, including optical coherence tomography (OCT), radiographic imaging, photoacoustic imaging, and thermography.
In an aspect, a catheter may include a catheter body having a proximal end and a distal end. The catheter may further include a deflectable member interconnected to the distal end. The deflectable member may include a motor.
In certain embodiments, the deflectable member may be hingedly connected to the distal end of the catheter body and operable for positioning across a range of angles relative to the catheter body. For example, the deflectable member may be connected to the distal end of the catheter body and operable for positioning across a range of angles relative to a longitudinal axis of the catheter body at the distal end. The deflectable member may further include a component, wherein the motor may effectuate movement of the component.
In certain embodiments, the movement may, for example, be rotational, pivotal, reciprocal, or any combination thereof (e.g., reciprocally pivotal). The component may be an ultrasound transducer array. The ultrasound transducer array may be configured for at least one of two dimensional imaging, three dimensional imaging and real-time three dimensional imaging. The catheter may have a minimum presentation width of less than about 3 cm. A length of a region of the catheter body in which deflection occurs when the deflectable member is deflected 90 degrees relative to the catheter body may be less than a maximum cross dimension of the catheter body.
The catheter body may comprise at least one steerable segment. For example, the steerable segment may be proximate to the distal end.
The catheter body may comprise a lumen. Such lumen may be for conveyance of a device (e.g., an interventional device) and/or material. In one embodiment, the lumen may extend form the proximal end to the distal end.
The catheter may include a hinge interconnecting the deflectable member and the catheter body. In one approach, the deflectable member may be supportably connected to the hinge. In certain embodiments, the hinge may, for example, be a living hinge or an ideal hinge, and the hinge may include a non-tubular bendable portion.
In another aspect, a catheter may include an outer tubular body, a deflectable member, and a hinge interconnecting the deflectable member and the outer tubular body. The deflectable member may include a motor. In an approach, the deflectable member may further include an ultrasound transducer array. The outer tubular body may comprise at least one steerable segment. The catheter may include an actuation device operable for active deflection of the deflectable member. The actuation device may, for example, include balloons, tether lines, wires (e.g., pull wires), rods, bars, tubes, hypotubes, stylets (including pre-shaped stylets), electro-thermally activated shape memory materials, electro-active materials, fluid, permanent magnets, electromagnets, or any combination thereof. The catheter may include a handle disposed at the proximal end. The handle may include a movable member to control the deflection of the deflectable member. The handle may include a mechanism, such as a worm gear arrangement or an active brake, capable of maintaining a selected deflection of the deflectable member.
In an arrangement, a catheter may include a catheter body having at least one steerable segment and a deflectable member. The deflectable member may include a component and a motor to effectuate movement of the component. In an embodiment, the catheter may include a hinge interconnecting the deflectable member and the catheter body.
In another aspect, a catheter may include a catheter body with at least one steerable segment, a deflectable member, a component supportably disposed on the deflectable member, and a motor supportably disposed on the deflectable member and operable for selective movement of the component. The deflectable member may be supportably disposed at a distal end of the catheter body and operable for selective deflectable positioning across a range of angles relative to the longitudinal axis of the catheter body at the distal end. In an approach, the component may be an ultrasound transducer array. The catheter may be configured such that a plane that may be perpendicular to a longitudinal axis of the deflectable member intersects both the component and the motor.
In yet another aspect, a catheter may include a catheter body and a deflectable member supportably disposed at a distal end of the catheter body and operable for selective deflectable positioning across a range of angles relative to the longitudinal axis of the catheter body. The catheter may further include a component disposed in the deflectable member. The component may be operable to move independently of the deflectable member, and the deflectable member may be operable to move independently from the catheter body.
In certain arrangements, a catheter may include a catheter body, a lumen, a deflectable member, and an electrical conductor member. The lumen may be for conveyance of a device and/or material, and may extend through at least a portion of the catheter body to a port located distal to a proximal end of the catheter body. The deflectable member may be located at a distal end of the catheter body and may include a motor and a component. The electrical conductor member may include a plurality of electrical conductors in an arrangement extending from the component to the catheter body. The arrangement may be bendable in response to deflection of the deflectable member. In an embodiment, the arrangement may comprise a flexboard arrangement. Such a flexboard arrangement may be bendable in response to oscillatory movement of the ultrasound transducer array. The flexboard arrangement may comprise a plurality of electrically conductive traces supportably disposed on a flexible, non-conductive substrate. In an approach, the flexboard arrangement may electrically interface with a plurality of conductors that extend from a proximal end to a distal end of the catheter body.
In an aspect, a catheter may include a catheter body, a lumen, and a deflectable member. The lumen may be configured for conveyance of a device and/or material and may extend through at least a portion of the catheter body to a port located distal to a proximal end of the catheter body. The deflectable member may be located at a distal end of the catheter body and may comprise a motor operable to effectuate movement of a component of the deflectable member. In an approach, the catheter may include a first electrical conductor portion and a second electrical conductor portion. The first electrical conductor portion may include a plurality of electrical conductors arranged with electrically non-conductive material therebetween, and may extend from the proximal end to the distal end. The second electrical conductor portion may be electrically interconnected to the first electrical conductor portion at the distal end and to an ultrasound transducer array. The second electrical conductor portion may be bendable in response to deflection of the deflectable member. The second electrical conductor portion may be bendable in response to oscillatory movement of the component.
In another arrangement, a catheter may include an outer tubular body, an inner tubular body, and a deflectable member. The inner tubular body may define a lumen therethrough for conveyance of a device and/or material. The outer tubular body and the inner tubular body may be disposed for selective relative movement therebetween. At least a portion the deflectable member may be permanently located outside of the outer tubular body at a distal end of the outer tubular body. The deflectable member may be supportability interconnected to the inner tubular body or the outer tubular body. Upon the selective relative movement, the deflectable member may be selectively deflectable in a predetermined manner. The deflectable member may include a component (e.g., an ultrasound transducer array) and a motor operable for movement of the component. In an embodiment, the deflectable member may be supportably interconnected to a hinge. The hinge may be supportably interconnected to the inner tubular body and restrainably interconnected to the outer tubular body. The catheter may further include a restraining member interconnected to the deflectable member and the outer tubular body. Upon advancement of the inner tubular body relative to the outer tubular body, a deflection force may be communicated to the deflectable member by the restraining member. The restraining member may be also a flexible electrical interconnection member.
In another aspect, a catheter may include a catheter body and a deflectable member. The catheter body may have at least one steerable segment. The deflectable member may be located at, and interconnected to, a distal end of the catheter body and may be selectively deflectable from a first position to a second position. The deflectable member may comprise a motor. In an example, the deflectable member may further comprise an ultrasound transducer array. The deflectable member may be interconnected to the catheter body by a tether, wherein the tether restrainably interconnects the deflectable member to the catheter body. A tether may be disposed between the deflectable member and the catheter body, and the tether may include a flexible electrical interconnection member.
In still another aspect, a catheter may include a catheter body, a deflectable member, and an ultrasound transducer array disposed on the deflectable member (e.g., within the deflectable member) for pivotal movement about a pivot axis. The catheter may further include a first electrical interconnection member having a first portion coiled and electrically interconnected to the ultrasound transducer array, a motor operable to produce the pivotal movement, and a hinge disposed between the catheter body and the deflectable member. In an approach, the catheter may include an enclosed volume. The first portion of the first electrical interconnection member may be disposed in a clock spring arrangement. The deflectable member may comprise a distal end and a proximal end, and the ultrasound transducer array may be disposed closer to the distal end than the first portion of the first electrical interconnection member, and the motor may be operable to pivot the ultrasound transducer array through at least about 360 degrees. A fluid may be disposed within the enclosed volume. A midline of the first portion of the first electrical interconnection member may be disposed within a single plane that may be disposed perpendicular to the pivot axis.
In an aspect, a catheter may include a catheter body, a deflectable member, an ultrasound transducer array, and a first electrical interconnection member. The catheter body may include a proximal end and a distal end. The deflectable member may be supportably disposed on the distal end of the catheter body and may have a portion having a first volume. The deflectable member may be deflectable relative to a longitudinal axis of the catheter body at the distal end. The ultrasound transducer array may be disposed for pivotal movement about a pivot axis within the first volume. The first electrical interconnection member may have a first portion coiled within the first volume and electrically interconnected to the ultrasound transducer array. In an embodiment, upon the pivotal movement, the coiled first portion of the first electrical interconnection member may tighten or loosen (e.g., the diameter of the coiled first portion may decrease or increase upon the pivotal movement). The coiled first portion may be configured such that pivoting in either direction (e.g., tightening or loosening) relative to a predetermined position requires force to overcome a resistance to such pivoting from the coiled first portion. The first electrical interconnection member may be ribbon-shaped and comprise a plurality of conductors arranged with electrically non-conductive material therebetween.
In an aspect, a catheter may include a deflectable member having a portion having an enclosed volume, a fluid disposed within the enclosed volume, an ultrasound transducer array, a first electrical interconnection member, and a hinge. The ultrasound transducer array may be disposed for reciprocal pivotal movement within the enclosed volume. The first electrical interconnection member may have at least a portion helically disposed within the enclosed volume and fixedly interconnected to the ultrasound transducer array. Upon the reciprocal movement, the helically disposed portion may loosen and tighten along a length thereof. The hinge may be disposed between the deflectable member and the catheter body.
In an arrangement, a catheter may include a catheter body, a deflectable member having a portion having an enclosed volume, a fluid disposed within the enclosed volume, a hinge, and a bubble-trap member. The hinge may be disposed between the deflectable member and the catheter body. The bubble-trap member may be fixedly positioned within the enclosed volume and have a distal-facing, concave surface. A distal portion of the enclosed volume may be defined distal to the bubble-trap member and a proximal portion of the enclosed volume may be defined proximal to the bubble-trap member. An aperture may be provided through the bubble-trap member to fluidly interconnect from the distal portion of the enclosed volume to the proximal portion of the enclosed volume.
In another arrangement, a catheter may include a deflectable member having a portion having an enclosed volume, a fluid disposed within the enclosed volume, an ultrasound transducer array disposed for movement within the enclosed volume, a hinge, and a bellows member. The bellows member may have a flexible, closed-end portion located in the fluid disposed within the enclosed volume and an open-end portion isolated from the fluid. The bellows member may be collapsible and expansible in response to volumetric variations in the fluid.
In yet another arrangement, a method for operating a catheter may include advancing a catheter body through a natural or otherwise-formed passageway in a patient, steering a distal end of the catheter body to a desired position, selectively deflecting a deflectable member hingedly connected to the distal end of the catheter body to one or more angles relative to the catheter body with the distal end of the catheter body maintained in the desired position, and operating a motor of the deflectable member to effectuate movement of an ultrasound transducer array to obtain at least two unique 2D images (i.e., images obtained with the ultrasound transducer array in two different orientations). The selective deflection may be achieved through an actuation device operable for selective deflection of the deflectable member. In an approach, the selective deflection step may be completed within a volume having a cross-dimension of about 3 cm or less.
In an aspect, a method for operating a catheter that includes a catheter body may include advancing the catheter through a passageway in a patient to a desired position such that a distal end of the catheter body is located at a first position. The catheter body may have at least one independently steerable segment and a deflectable member supportably disposed at the distal end of the catheter body. The method may further include deflecting the deflectable member to a desired angular position within a range of viewing angles relative to the distal end of the catheter body with the distal end maintained in the first position. The method may further include operating a motor supportably disposed on the deflectable member with the deflectable member in the desired angular position, for driven movement of an ultrasound transducer array supportably disposed on the deflectable member. In an embodiment, the method may further include steering the catheter body by flexure along a length thereof. The deflecting step may comprise deforming a hinge (which interconnects the distal end of the catheter body and the deflectable member) from a first configuration to a second configuration. In an embodiment, the method may further include advancing or retrieving a device or material through a port at the distal end of the catheter body and into an imaging volume of the ultrasound transducer array during the operating step.
The deflectable member may have a round cross-sectional profile. The deflectable member may include an enclosed volume and a sealable port. In one aspect, the deflectable member may include at least one sealable fluid filling port that allows the enclosed volume to be filled with a fluid, e.g., one that will facilitate acoustic coupling. The sealable port may be used to fill the enclosed volume of the deflectable member with fluid and then it may be sealed. Filling of the enclosed volume through the sealable port may be achieved by the temporary insertion of a syringe needle. At least one additional sealable port may be included for the exit of enclosed air during the fluid filling step.
In an embodiment, the deflectable member may include a motor disposed within the enclosed volume and operatively interconnected to an imaging device, e.g., an ultrasound transducer array. The motor drives the array for the reciprocal pivotal movement.
In an embodiment, the deflectable member may include a portion having an enclosed volume and an ultrasound transducer array disposed within the enclosed volume. In certain embodiments the deflectable member may further include a fluid (e.g., a liquid) disposed within the enclosed volume. In such embodiments, an ultrasound transducer array may be surrounded by the fluid to facilitate acoustic coupling. In certain embodiments the ultrasound transducer array may be disposed for reciprocal pivotal movement within the enclosed volume, thereby yielding three-dimensional images of internal body anatomy.
In one aspect, the deflectable member may include a bellows member having a flexible, closed-end portion located within the fluid in the enclosed volume and an open-end isolated from the fluid, wherein the bellows member is collapsible and expansible in response to volumetric variations in the fluid. As may be appreciated, the provision of a bellows member may maintain operational integrity of the deflectable member when exposed to conditions that may cause a volumetric change in the contained fluid.
At least the closed end portion of the bellows member may be elastically deformable. In this regard, the closed end portion of the bellows member may be elastically expandable in response to volumetric variations in the fluid. The bellows member may be operable to maintain operational integrity of the deflectable member despite fluid volume changes that may occur due to exposure of the deflectable member to relatively warm or cool temperatures during, for example, transport and/or storage. Such an elastically expandable bellows member may be particularly advantageous with respect to low temperatures where the fluid typically contracts more than the deflectable member.
In another aspect, the deflectable member may include a bubble-trap member fixedly positioned relative to the enclosed volume and a fluid disposed within the enclosed volume. The bubble-trap member may have a distal-facing concave surface, wherein a distal portion of the enclosed volume is defined distal to the bubble-trap member and a proximal portion of the enclosed volume is defined proximal to the bubble-trap member. The ultrasound transducer array may be located in the distal portion and an aperture may be provided through the bubble-trap member to fluidly connect the distal portion of the enclosed volume to the proximal portion of the enclosed volume.
As may be appreciated, bubbles present in the contained fluid can negatively affect images obtained by the ultrasound transducer array and are undesired. In the described arrangement, the deflectable member may be oriented with the proximal end upwards, wherein bubbles may be directed by the concave surface through the aperture of the bubble-trap, and effectively isolated from the ultrasound transducer array by virtue of the bubbles being trapped in the proximal portion of the enclosed volume by the bubble-trap. In another method of controlling bubble location, a user may grasp the catheter at a point proximal to the enclosed volume and swing around the portion with the enclosed volume to impart centrifugal force on the fluid within the enclosed volume thereby causing the fluid to move toward the distal end and any bubbles within the fluid to move towards the proximal portion of the enclosed volume.
In an arrangement, a filter may be disposed across the aperture. The filter may be configured such that air may pass through the aperture while the fluid may be unable to pass through the aperture. The filter may include expanded polytetrafluoroethylene (ePTFE).
In an embodiment, the ultrasound transducer array may be disposed for reciprocal pivotal movement within the enclosed volume, and a gap between the ultrasound transducer array and an inner wall of the enclosed volume may be sized such that fluid is drawn into the gap via capillary forces. To achieve such a gap, the ultrasound transducer array may include a cylindrical enclosure disposed about the array and the gap may exist between the outer diameter of the cylindrical enclosure and the inner wall of the enclosed volume.
In an aspect, the deflectable member may include a catheter having a portion having an enclosed volume, an imaging device such as an ultrasound transducer array disposed for reciprocal pivotal movement about a pivot axis within the enclosed volume, and an electrical interconnection member having a first portion coiled (e.g., coiled in a single plane in a clock spring arrangement, coiled along an axis in a helical arrangement) within the enclosed volume and electrically interconnected to the imaging device. In an arrangement, the first portion of the electrical interconnection member may be helically disposed within the enclosed volume about a helix axis. As the imaging device is pivoted, the helically wrapped first portion may tighten and loosen about the helix axis. The pivot axis may be coincident with the helix axis. The enclosed volume may be disposed at a distal end of the deflectable member. A fluid may be disposed within the enclosed volume.
In another further aspect, the imaging device, e.g., an ultrasound transducer array may be disposed for reciprocal movement about a pivot axis within the enclosed volume. The deflectable member may further include at least a first electrical interconnection member (e.g. for conveying imaging signals to/from the imaging device). The first electrical interconnection member may include a first portion coiled about the pivot axis and interconnected to the ultrasound transducer array.
In an embodiment, the first electrical interconnection member may include a second portion adjoining the first portion, wherein the second portion is fixedly positioned relative to a catheter body, and wherein upon reciprocal movement of the imaging device, the coiled first portion of the first electrical interconnection member tightens and loosens about the pivot axis. The second portion of the first electrical interconnection member may be helically and fixedly positioned about an inner core member disposed within the catheter body.
In one approach, the first electrical interconnection member may be ribbon-shaped and may comprise a plurality of conductors arranged side-by-side with electrically non-conductive material disposed therebetween across the width of the member. By way of example, the first electrical interconnection member may comprise a GORE™ Micro-Miniature Ribbon Cable available from WL Gore & Associates, Newark, Del., U.S.A, wherein the first portion of the first electrical interconnection member may be disposed so that a top or bottom side thereof faces and wraps about a pivot axis of an ultrasound transducer array.
In another embodiment, the first portion of the electrical interconnection member may be coiled a plurality of times about the pivot axis. More particularly, the first portion of the first electrical interconnection member may be helically disposed about the pivot axis a plurality of times. In one approach, the first electrical interconnection member may be helically disposed about the pivot axis in a non-overlapping manner, i.e. where no portion of the first electrical interconnection member overlies another portion thereof.
In another approach, the first electrical interconnection member may be ribbon-shaped and may be helically disposed about the pivot axis a plurality of times. Upon reciprocal pivotal movement of the ultrasound transducer array, the helically wrapped, ribbon shaped portion may tighten and loosen about the helix axis. The deflectable member may further include a motor operable to produce the reciprocal pivotal movement. A flexboard may be electrically interconnected to the imaging device and the flexboard may electrically interconnect to the first electrical interconnection member at a location between the motor and an outer wall of the catheter. The interconnection between the flexboard and the first electrical interconnection member may be supported by a cylindrical interconnection support.
The deflectable member may be configured such that the imaging device is disposed distally along the deflectable member relative to the first portion of the first electrical interconnection member. In an alternate arrangement, the deflectable member may be configured such that the first portion of the first electrical interconnection member is disposed distally relative to the imaging device. In such an alternate arrangement, a portion of the first electrical interconnection member may be fixed relative to a tip case of the deflectable member where the first electrical interconnection member passes the imaging device. In either arrangement, the first portion may be coiled within the enclosed volume.
In an arrangement, the deflectable member may include a driveshaft operatively interconnected to the imaging device. The driveshaft may be operable to drive the imaging device for the reciprocal pivotal movement. The driveshaft may extend from the proximal end of the deflectable member to the imaging device. The driveshaft may be driven by a motor.
In an embodiment, the first portion of the first electrical interconnection member may be disposed in a clock spring arrangement. A center line of the first portion of the first electrical interconnection member may be disposed within a single plane that is in turn disposed perpendicular to the pivot axis. The deflectable member includes a distal end and a proximal end, and in an arrangement, the first portion (the clock spring) may be disposed closer to the distal end of the deflectable member than the imaging device. The first portion may comprise a flexboard.
In an aspect, the catheter may include a deflectable member, an imaging device, and at least a first electrical interconnection member. The deflectable member may have a portion having a first volume that may be open to an environment surrounding at least a portion of the deflectable member. The imaging device may be disposed for reciprocal pivotal movement about a pivot axis within the first volume. In this regard, the imaging device may be exposed to fluid (e.g., blood) present in the environment surrounding the deflectable member. The first electrical interconnection member may have a first portion coiled within the first volume and electrically interconnected to the imaging device. In an embodiment, the first portion of the first electrical interconnection member may be helically disposed within the first volume about a helix axis. The first electrical interconnection member may further include a second portion adjoining the first portion. The second portion may be fixedly positioned relative to a case partially surrounding the first volume. Upon the reciprocal pivotal movement, the coiled first portion of the first electrical interconnection member may tighten and loosen. The first electrical interconnection member may be ribbon-shaped and include a plurality of conductors arranged side-by-side with electrically non-conductive material therebetween. The first portion of the first electrical interconnection member may be disposed in a clock spring arrangement. The clock spring arrangement may be disposed within the first volume that may be open to the environment surrounding at least a portion of the deflectable member. A structure may surround the imaging device. For example, an acoustically-transmissive structure, capable of focusing, defocusing, or transmitting without altering, acoustic energy may fully or partially surround an ultrasound transducer array. The structure may have a round cross-sectional profile. Such a profile, especially if rounded, may reduce turbulence in the surrounding blood, reduce damage to the surrounding blood cells, and aid in avoiding thrombus formation while the imaging device is undergoing reciprocal pivotal movement.
In another aspect, a method is provided for operating a catheter having a deflectable imaging device located at a distal end thereof. A deflectable imaging device may be in the form of a deflectable member that includes componentry for the generation of images. The method may include moving the distal end of the catheter from an initial position to a desired position and obtaining image data from the deflectable imaging device during at least a portion of the moving step. The deflectable imaging device may be located in a first position during the moving step. Moving to the desired position may include the utilization of steering controls in the catheter to direct the catheter orientation within the anatomy. The method may further include utilizing the image data to determine when the catheter is located at the desired position, deflecting the deflectable imaging device relative to the distal end of the catheter from the first position to a second position after the moving step; and optionally advancing an interventional device through an optional port at the distal end of the catheter and into an imaging field of view of the deflectable imaging device in the second position.
In an arrangement, the deflecting step may further include translating a proximal end of at least one of an outer tubular body of the catheter and actuation device of the catheter relative to a proximal end of the other one of the outer tubular body and actuation device.
A deflection force may be applied to a hinge in response to the translating step. The deflectable imaging device may be supportably interconnected by the hinge to one of the catheter body and the actuation device. The deflection force may be initiated in response to the translating step. The deflection force may be communicated in a balanced and distributed manner about a central axis of the outer tubular body. Communicating the deflection force in such a manner may reduce undesirable bending and/or whipping of the catheter.
In an arrangement, the position of the deflectable imaging device may be maintained relative to the distal end of the catheter during the moving and obtaining steps. In an embodiment, the deflectable imaging device may be side-looking in the first position and forward-looking or rearward-looking in the second position. In an embodiment, the imaging field of view may be maintained in a substantially fixed registration relative to the distal end of the catheter during the advancing step.
The following aspects describe catheters including a deflectable member. Although not mentioned, such deflectable members may include motors for selective driven movement of a component or components within the deflectable member. For example, where appropriate, the deflectable members described hereinafter may each include a motor for selective driven movement of the ultrasound transducer arrays.
In an additional aspect, at least a portion of the deflectable member may be permanently located outside of the outer tubular body. In this regard, the deflectable member may be selectively deflectable away from a central axis of the outer tubular body. In certain embodiments, such deflectability may be at least partially or entirely distal to the distal end of the outer tubular body.
In one aspect, the catheter may also include a lumen for conveyance of a device and/or material such as delivering an interventional device extending through the outer tubular body from the proximal end of the outer tubular body to a point distal thereto. For purposes hereof, “interventional device” includes without limitation diagnostic devices (e.g., pressure transducers, conductivity measurement devices, temperature measurement devices, flow measurement devices, electro- and neuro-physiology mapping devices, material detection devices, imaging devices, central venous pressure (CVP) monitoring devices, intracardiac echocardiography (ICE) catheters, balloon sizing catheters, needles, biopsy tools), therapeutic devices (e.g., ablation catheters (e.g., radio-frequency, ultrasonic, optical), patent foramen ovale (PFO) closure devices, cryotherapy catheters, vena cava filters, stents, stent-grafts, septostomy tools), and agent delivery devices (e.g., needles, cannulae, catheters, elongated members). For purposes hereof, “agent” includes without limitation therapeutic agents, pharmaceuticals, chemical compounds, biologic compounds, genetic materials, dyes, saline, and contrast agents. The agent may be liquid, gel, solid, or any other appropriate form. Furthermore, the lumen may be used to deliver agents therethrough without the use of an interventional device. The combinative inclusion of a deflectable member and lumen for conveyance of a device and/or material therethrough facilitates multi-functionality of the catheter. This is advantageous because it reduces the number of catheters and access sites required during the procedure, provides the potential to limit the interventional procedure time, and enhances ease of use.
In this regard, in certain embodiments the lumen may be defined by an inside surface of the wall of the outer tubular body. In other embodiments, the lumen may be defined by an inside surface of an inner tubular body located within the outer tubular body and extending from the proximal end to the distal end thereof.
In another aspect, a deflectable member may be selectively deflectable through an arc of at least about 45 degrees, and in various implementations at least about 90 degrees, and in other embodiments an arc of at least about 180, about 200, about 260, or about 270 degrees. For example, the deflectable member may be deflectable in a pivot-like manner about a pivot, or hinge, axis through an arc of at least about 90 degrees or at least about 200 degrees. Further, the deflectable member may be selectively deflectable and maintainable at a plurality of positions across a range of different angled positions. Such embodiments are particularly apt for implementing a deflectable member comprising an imaging device.
In certain embodiments, a deflectable member in the form of a deflectable imaging device may be selectively deflectable from an exposed (e.g., where at least a portion of the aperture of the deflectable imaging device is free from interference from the outer tubular body) side-looking first position to an exposed forward-looking, second position. “Side-looking” as used herein is defined as the position of the deflectable imaging device where the field of view of the deflectable imaging device is oriented substantially perpendicular to the distal end of the outer tubular body center axis, i.e., central axis. “Forward-looking” includes where the imaging field of view of the deflectable imaging device is at least partially deflected to enable imaging of a volume that includes regions distal to the distal end of the catheter. For example, a deflectable imaging device (e.g., an ultrasound transducer array) may be aligned with (e.g., disposed parallel to or coaxially with) a central axis of the outer tubular body in a first position. Such an approach accommodates introduction into a vessel or body cavity and imaging of anatomical landmarks during catheter positioning (e.g., during insertion and advancement of the catheter into a vascular passageway or bodily cavity), wherein anatomical landmark images may be employed to precisely position a port of a lumen comprising the catheter. In turn, the ultrasound transducer array may be deflected from the side-looking, first position to a forward-looking, second position (e.g., angled at least about 45 degrees, or in some applications at least about 90 degrees) relative to a central axis of the catheter. An interventional device may then be selectively advanced through a lumen of the catheter and into a work area located adjacent to a lumen port and within an imaging field of view of the ultrasound transducer array, wherein imaged internal procedures may be completed utilizing the interventional device with imaging from the ultrasound transducer array alone or in combination with other imaging modalities (e.g., fluoroscopy). The deflectable imaging device may be deflected such that no part of the deflectable imaging device occupies a volume with the same cross section as the port and extending distally from the port. As such, the imaging field of view of the deflectable imaging device may be maintained in a fixed registration relative to the outer tubular body while the interventional device is being advanced through the outer tubular body, through the port, and into the imaging field of view of the deflectable imaging device.
In certain embodiments, a deflectable imaging device may be selectively deflectable from a side-looking first position to a rearward-looking, second position. “Rearward-looking” includes where the imaging field of view of the deflectable imaging device is at least partially deflected to enable imaging of a volume that includes regions proximal to the distal end of the catheter.
In other embodiments, a deflectable imaging device may be selectively deflectable from a side-looking first position to a variety of selected forward-looking, side-looking and rearward-looking positions thereby enabling the acquisition of multiple imaging planes or volumes within the patient anatomy while preferably maintaining a relatively-fixed or stable catheter position. An ultrasound transducer array may be configured to obtain volumetric imaging and color flow information in which the center beam of the volume can be redirected by such deflection of the transducer. This is particularly beneficial for embodiments for real-time rendering of sequential three dimensional images using a deflectable imaging device with an oscillating one dimensional array or stationary two-dimensional array. In such embodiments, the angle of orientation of the ultrasound transducer array, and deflectable member, relative to the longitudinal axis of the catheter body can be any angle between about +180 degrees to about −180 degrees or an arc of at least about 180, about 200, about 260, or about 270 degrees. Angles contemplated include about +180, +170, +160, +150, +140, +130, +120, +110, +100, +90, +80, +70, +60, +50, +40, +30, +20, +10, 0, −10, −20, −30, −40, −50, −60, −70, −80, −90, −100, −110, −120, −130, −140, −150, −160, −170, and −180 degrees or can fall within or outside of any two of these values.
In a related aspect, a deflectable member may comprise an ultrasound transducer array having an aperture length at least as large as a maximum cross-dimension of the outer tubular body. Correspondingly, the deflectable ultrasound transducer array may be provided for selective deflection from a first position that accommodates advancement of the catheter through a vascular passageway to a second position that is angled relative to the first position. Again, in certain embodiments the second position may be selectively established by a user.
In a related aspect, deflectable member may be deflectable from a first position aligned with the central axis of the catheter (e.g., parallel thereto) to a second position angled relative to the central axis, wherein when in the second position the deflectable member is disposed outside of a working area located adjacent to a lumen port. As such, an interventional device may be advanceable through the port free from interference with the deflectable member.
In certain embodiments, the deflectable member may be provided so that the cross-sectional configuration thereof generally coincides with the cross-sectional configuration of the outer tubular body at the distal end thereof. For example, when a cylindrically-shaped outer tubular body is employed, a deflectable member may be located beyond the distal end of the outer tubular body and configured to coincide with (e.g., slightly exceed, occupy, or fit within) an imaginary cylindrical volume defined by and adjacent to such distal end, wherein the deflectable member is selectively deflectable out of such volume. Such an approach facilitates initial advancement and positioning of the catheter through vascular passageways.
In certain embodiments, a deflectable member may be provided to deflect along an arc path that extends away from a central axis of the outer tubular body. By way of example, in various implementations the deflectable member may be disposed to deflect from a first position that is located distal to a lumen port, to a second position that is lateral to the outer tubular body (e.g., to one side of the outer tubular body).
In another aspect, a deflectable member may be provided to deflect from a longitudinal axis, e.g., the central axis of the catheter. Upon a deflection of 90 degrees from the longitudinal axis, a displacement arc is defined. The displacement arc is the minimum constant-radius arc that is tangent to a face of the deflectable member and tangent to a straight line collinear with the central axis of the catheter at the most distal point of the catheter. The displacement arc associated with a particular embodiment of a deflectable member may be used to compare the deflection performance of that particular embodiment to other deflectable member embodiments and to a minimum bend radius of a steered catheter (in cases where the rigid tip is positioned using only conventional steering). In an aspect, the radius of the displacement arc may be less than about 1 cm. In an aspect, a deflectable member may be provided wherein a ratio of a maximum cross-dimension of the distal end of the outer tubular body to the radius of the displacement arc is at least about 1. By way of example, for a cylindrical outer tubular body, the ratio may be defined by the outer diameter of the distal end of the outer tubular body over the displacement arc radius, wherein such ratio may be advantageously established to be at least about 1.
In an aspect, a catheter with a deflectable member may be provided where the deflectable member may deflect from a longitudinal axis, and where upon a deflection of 90 degrees from the longitudinal axis, a region over which deflection occurs is defined. The region over which deflection occurs is the region along the length of the catheter in which a curvature or other change is introduced in order to achieve the 90 degree deflection. In the case of an ideal hinge, the region over which deflection occurs would be a point. In the case of a living hinge, the region over which deflection occurs approximates a point. In certain embodiments, the region over which deflection occurs may be less than a maximum cross dimension of a catheter body.
In another aspect, a deflectable member may be interconnected to the catheter body wall at the distal end of the outer tubular body. As will be further described, such interconnection may provide support functionality and/or selective deflection functionality. In the latter regard, the deflectable member may be deflectable about a deflection axis that is offset from a central axis of the outer tubular body. For example, the deflection axis may lie in a plane that extends transverse to the central axis of an outer tubular body and/or in a plane that extends parallel to the central axis. In the former regard, in one embodiment the deflection axis may lie in a plane that extends orthogonal to the central axis. In certain implementations, the deflection axis may lie in a plane that extends tangent to a port of a lumen that extends through the outer tubular body of the catheter.
In yet another aspect, the catheter may comprise a lumen (e.g., for delivering an interventional device) extending from the proximal end to an port located at the distal end of the outer tubular body, wherein the port has a central axis coaxially aligned with a central axis of the outer tubular body. Such an arrangement facilitates the realization of relatively small catheter cross-dimensions, thereby enhancing catheter positioning (e.g., within small and/or tortuous vascular passageways). The deflectable member may also be disposed for deflection away from the coaxial central axes, thereby facilitating angled lateral positioning away from the initial catheter introduction (e.g., 0 degree) position of the deflectable member. In certain embodiments, the deflectable member may be deflectable through an arc of at least about 90 degrees or at least about 200 degrees.
In a further aspect, the catheter may include an actuation device, extending from the proximal end to the distal end of the outer tubular body, wherein the actuation device may be interconnected to the deflectable member. Actuation devices may, for example, include balloons, tether lines, wires (e.g., pull wires), rods, bars, tubes, hypotubes, stylets (including pre-shaped stylets), electro-thermally activated shape memory materials, electro-active materials, fluid, permanent magnets, electromagnets, or any combination thereof. The actuation device and outer tubular body may be disposed for relative movement such that the deflectable member is deflectable through an arc of at least about 45 degrees in response to 0.5 cm or less relative movement between the actuation device and the outer tubular body. By way of example, in certain embodiments the deflectable member may be deflectable through an arc of at least about 90 degrees in response to 1.0 cm or less relative movement of the actuation device and outer tubular body.
In a further aspect, the deflectable member may be interconnected to the outer tubular body. In one approach, the deflectable member may be supportably interconnected to the outer tubular body at the distal end thereof. In turn, an actuation device comprising one or more elongate members (e.g., of wire-like construction) may be disposed along the outer tubular body and interconnected at a distal end to the deflectable member, wherein upon applying a tensile or compressive force (e.g., a pull or push force) to a proximal end of the elongate member(s) the distal end of the elongate member(s) may cause the deflectable member to deflect. In this approach, the outer tubular body may define a lumen therethrough (e.g., for delivering an interventional device) extending from the proximal end of the outer tubular body to a port located distal to the proximal end.
In another approach, a deflectable member may be supportably interconnected to one of the outer tubular body and an actuation device, and restrainably interconnected by a restraining member (e.g., a ligature) to the other one of the outer tubular body and actuation device, wherein upon relative movement of the outer tubular body and actuation device the restraining member restrains movement of the deflectable member to affect deflection thereof.
For example, the deflectable member may be supportably interconnected to an actuation device and restrainably interconnected to the outer tubular body at the distal end thereof. In this approach, the actuation device may comprise an inner tubular body defining a lumen therethrough (e.g., for delivering an interventional device) extending from the proximal end of the catheter body to a port located distal to the proximal end.
More particularly, and in a further aspect, the catheter may comprise an inner tubular body, disposed within the outer tubular body for relative movement therebetween (e.g., relative slidable movement). A deflectable member located at the distal end may be supportably interconnected to the inner tubular body. In certain embodiments, the deflectable member may be disposed so that upon selective relative movement of the outer tubular body and inner tubular body the deflectable member is selectively deflectable and maintainable in a desired angular orientation.
For example, in one implementation an inner tubular body may be slidably advanced and retracted relative to an outer tubular body, wherein engagement between surfaces of the two components provides a mechanism interface sufficient to maintain a selected relative position of the two components and corresponding deflected position of the deflectable member. A proximal handle may also be provided to facilitate the maintenance of selected relative positioning of the two components.
In an additional aspect, the catheter may include an actuation device, extending from a proximal end to a distal end of the outer tubular body and moveable relative to the outer tubular body to apply a deflection force to the deflectable member. In this regard, the actuation device may be provided so that deflection force is communicated by the actuation device from the proximal end to the distal end in a balanced and distributed manner about a central axis of the outer tubular body. As may be appreciated, such balanced and distributed force communication facilitates the realization of a non-biased catheter yielding enhanced control and positioning attributes.
In an embodiment, the deflectable member may be operable by the actuation device for selective positioning. In another embodiment, the operation of the actuation device may be independent from steering of the catheter body. In a further embodiment, the operation of the actuation device may operate independently from steering of the catheter and independently from the operation of a motor for driven oscillatory movement of the ultrasound transducer array as described below.
In conjunction with one or more of the above-noted aspects, the catheter may include a hinge that is supportably interconnected to the outer tubular body or, in certain embodiments, to an included actuation device (e.g., an inner tubular body). The hinge may be structurally separate from and fixedly interconnected to the catheter body (e.g., the outer tubular body or the inner tubular body). The hinge may be further fixedly interconnected to the deflectable member, wherein the deflectable member is deflectable in a pivot-like manner. In certain embodiments the hinge may be constructed from the catheter body (e.g., the catheter body may have a portion removed and the remaining portion maybe used as a hinge). The hinge member may be at least partially elastically deformable to deform from a first configuration to a second configuration upon the application of a predetermined actuation force, and to at least partially return from the second configuration to the first configuration upon removal of the predetermined actuation force. Such functionality facilitates the provision of a deflectable member that may be selectively actuated via an actuation device to move from an initial first position to a desired second position upon the application of a predetermined actuation force (e.g., a tensile or pulling force, or a compressive pushing force applied thereto), wherein upon selective release of the actuation force the deflectable member may automatically at least partially retract to its initial first position. In turn, successive deflectable positioning/retraction of the deflectable member may be realized during a given procedure, thereby yielding enhanced functionality in various clinical applications.
In certain embodiments, the hinge member may be provided to have a column strength sufficient to reduce unintended deflection of the deflectable member during positioning of the catheter (e.g., due to mechanical resistance associated with advancement of the catheter). By way of example, the hinge member may exhibit a column strength at least equivalent to that of the outer tubular body.
In certain implementations the hinge may be a portion of a one-piece, integrally defined member. For example, the hinge may comprise a shape memory material (e.g., Nitinol). In one approach, the hinge member may include a curved first portion and a second portion interconnected thereto, wherein the second portion is deflectable about a deflection axis defined by the curved first portion. By way of example, the curved first portion may comprise a cylindrically-shaped surface. In one embodiment, the curved first portion may include two cylindrically-shaped surfaces having corresponding central axes that extend in a common plane and intersect at an angle, wherein a shallow, saddle-like configuration is defined by the two cylindrically-shaped surfaces. In an approach, the hinge member may include a pintle. In an approach, the hinge member may include a membrane that is bendable such that the deflectable member is operable to move through a predefined path at least partially controlled by the membrane.
In yet a further aspect, the outer tubular body may be constructed to facilitate the inclusion of electrical componentry at the distal end thereof. More particularly, the outer tubular body may comprise a plurality of interconnected electrical conductors extending from the proximal end to the distal end. For example, in certain embodiments the electrical conductors may be interconnected in a ribbon-shaped member that is helically disposed about and along all or at least a portion of a catheter central axis, thereby yielding enhanced structurally qualities to the wall of the outer tubular body and avoiding excessive strain on the electrical conductors during flexure of the outer tubular body. For example, in certain embodiments the electrical conductors may be braided along at least a portion of the catheter central axis, thereby yielding enhanced structurally qualities to the wall of the outer tubular body. The outer tubular body may further include a first layer disposed inside of the first plurality of electrical conductors and extending from the proximal end to the distal end, and a second layer disposed on the outside of the first plurality of electrical conductors, extending from the proximal end to the distal end. The first tubular layer and second tubular layer may each be provided to have a dielectric constant of about 2.1 or less, wherein capacitive coupling may be advantageously reduced between the plurality of electrical conductors and bodily fluids present outside of the catheter and within a lumen extending through the outer tubular body.
In yet another aspect, a catheter may include a tubular body. The tubular body may include a wall with a proximal end and a distal end. The wall may include first and second layers extending from the proximal end to the distal end. The second layer may be disposed outside of the first layer. The first and second layers may each have a withstand voltage of at least about 2,500 volts AC. The wall may further include at least one electrical conductor extending from the proximal end to the distal end and disposed between the first and second layers. A lumen may extend through the tubular body. Combined, the first and second layers may provide an elongation resistance such that a tensile load of about 3 pound-force (lbf) (13 Newton (N)) results in no more than a 1 percent elongation of the tubular body.
In an arrangement, the tubular body may provide an elongation resistance such that a tensile load of about 3 lbf (13 N) applied to the tubular body results in no more than a 1 percent elongation of the tubular body, and in such an arrangement at least about 80 percent of the elongation resistance may be provided by the first and second layers.
In an embodiment, the first and second layers may have a combined thickness of at most about 0.002 inches (0.05 millimeters (mm)). Moreover, the first and second layers may have a combined elastic modulus of at least about 345,000 pounds per square inch (psi) (2,379 megapascal (MPa)). The first and second layers may exhibit a substantially uniform tensile profile about the circumference and along the length of the tubular body when a tensile load is applied to the tubular body. The first and second layers may each include helically wound material (e.g., film). For example, the first layer may include a plurality of helically wound films. A first portion of the plurality of films may be wound in a first direction, and a second portion of the films may be wound in a second direction that is opposite from the first direction. One or more of the plurality of films may include a high-strength tensilized film. One or more of the plurality of films may include non-porous fluoropolymer. The non-porous fluoropolymer may comprise non-porous ePTFE. The second layer may be constructed similarly to the first layer. The at least one electrical conductor may be in the form of a multiple conductor ribbon and/or conductive thin film and may be helically wrapped along at least a portion of the tubular body.
As will be appreciated, the construction of the tubular body of the current aspect may be utilized in other aspects described herein such as, for example, aspects where a tubular body is disposed within another tubular body and relative motion between the tubular bodies is used to deflect a deflectable member.
In an embodiment of the current aspect the first and second layers may have a combined thickness of at most about 0.010 inches (0.25 mm). Moreover, the first and second layers may have a combined elastic modulus of at least about 69,000 psi (475.7 MPa). In the present embodiment, the first layer may comprise a first sub-layer of the first layer and a second sub-layer of the first layer. The first sub-layer of the first layer is disposed inside the second sub-layer of the first layer. The second layer may comprise a first sub-layer of the second layer and a second sub-layer of the second layer. The first sub-layer of the second layer is disposed outside the second sub-layer of the first layer. The first sub-layer of the first layer and the first sub-layer of the second layer may include a first type of helically wound film. The second sub-layer of the first layer and the second sub-layer of the second layer may include a second type of helically wound film. The first type of helically wound film may include non-porous fluoropolymer and the second type of helically wound film may include porous fluoropolymer.
In another embodiment, the first layer may have a thickness of at most about 0.001 inches (0.025 mm) and the second layer may have a thickness of at most about 0.005 inches (0.13 mm). Moreover, the first layer may have an elastic modulus of at least about 172,500 psi (1,189 MPa) and the second layer may have an elastic modulus of at least about 34,500 psi (237.9 MPa).
In another aspect, the outer tubular body may comprise a plurality of electrical conductors extending from a proximal end to the distal end and a set of tubular layers inside and/or outside of the first plurality of electrical conductors. The set of tubular layers may comprise a low dielectric constant layer (e.g., located closest to the electrical conductors), and a high withstand voltage layer. In this regard, the low dielectric constant layer may have a dielectric constant of 2.1 or less, and the high withstand voltage layer may be provided to yield a withstand voltage of at least about 2500 volts AC. In certain embodiments, a set of low dielectric and high withstand voltage layers may be provided both inside and outside of the plurality of electrical conductors along the length of the outer tubular body.
In certain embodiments tie layers may be interposed between the electrical conductors and one or more inner and/or outer layers. By way of example, such tie layers may comprise a film material that may have a melt temperature that is lower than other components of the outer tubular body, wherein the noted layers of components may be assembled and the tie layers selectively melted to yield an interconnected structure. Such selectively melted tie layers may prevent other layers of the outer tubular body from migrating relative to each other during manipulation of the outer tubular body (e.g., during insertion into a patient).
For some arrangements, the outer tubular body may further include a shielding layer disposed outside of the electrical conductors. By way example, the shielding layer may be provided to reduce electromagnetic interference (EMI) emissions from the catheter as well as shield the catheter from external EMI.
In certain embodiments, lubricious inside and outside layers and/or coatings may also be included. That is, an inner layer may be disposed within the first tubular layer and an outer layer may be disposed outside of the second tubular layer.
In yet a further aspect, the catheter may be provided to comprise a first electrical conductor portion extending from a proximal end to a distal end of the catheter, and a second electrical conductor portion electrically interconnected to the first electrical conductive portion at the distal end. The first electrical conductor portion may comprise a plurality of interconnected electrical conductors arranged side-by-side with electrically non-conductive material therebetween. In certain implementations, the first electrical conductor portion may be helically disposed about a catheter central axis from the proximal end to the distal end thereof. In conjunction with such implementations, the second electrical conductor portion may comprise a plurality of electrical conductors interconnected to the plurality of interconnected electrical conductors of the first electrical conductor portion, and extending parallel to a central axis of the outer tubular body at the distal end. In certain embodiments, the first electrical conductor portion may be defined by a ribbon-shaped member included within the wall of the outer tubular body, thereby contributing to the structural integrity thereof.
In conjunction with the noted aspect, the first electrical conductor portion may define a first width across the interconnected plurality of electrical conductors, and the second electrical conductor portion may define a second width across the corresponding plurality of electrical conductors. In this regard, the second electrical conductor portion may be defined by electrically conductive traces disposed on a substrate. By way of example, the substrate may extend between the end of the first electrical conductor portion and electrical componentry provided at the distal end of a catheter, including for example an ultrasound transducer array.
In various embodiments, the second electrical conductor portion may be interconnected to a deflectable member and may be of a bendable construction, wherein at least a portion of the second electrical conductor portion is bendable with and in response to deflection of the deflectable member. More particularly, the second electrical conductor portion may be defined by electrically conductive traces on a substrate that is bendable in tandem with a deflectable member through an arc of at least about 90, 180, 200, 260, or 270 degrees.
In a further aspect, the catheter may comprise a deflectable member that includes an ultrasound transducer array, wherein at least a portion of the deflectable ultrasound transducer array may be located within the outer tubular body wall at the distal end. Further, the catheter may include steering means whereby the catheter body can be directed within the anatomy to a preferred location within a cavity, chamber of the heart or for access to a vascular lumen. Still further, the catheter may include a lumen (e.g., for delivering an interventional device) extending from the proximal end to a point distal thereto.
In yet another aspect, the catheter may comprise a motor to effectuate oscillatory or rotary movement of an imaging device, e.g., an ultrasound transducer array. The ultrasound transducer array may be disposed for reciprocal pivotal movement (i.e., rotating back and forth, rather than continuously around, for example, the catheter body central axis, or an axis parallel thereto, with the motor operable for driving the movement. As used herein, the term “rotating” refers to oscillatory or angular motion or movement between a selected +/− degrees of angular range. Oscillatory or angular motion includes but is not limited to partial motion in a clock-wise or counter-clockwise direction or motion between a positive and negative range of angular degrees. A motor includes micro-motors, actuators, microactuators, such as electromagnetic motors including stepper motors, inductive motors or synchronous motor (e.g., Faulhaber Series 0206 B available from MicroMo Electronics, Inc., Clearwater, Fla., U.S.A.); shape memory material actuator mechanisms, such as disclosed in US 2007/0016063 by Park et al.; active and passive or active magnetic actuators; ultrasonic motors (e.g., Squiggle® motors available from New Scale Technologies, Victor, N.Y., U.S.A.); hydraulic or pneumatic drives such as or any combination thereof. The motor may reside in a member that may be moved relative to the catheter body, or may be external from the catheter body, or in the catheter body. The motor may be located in a liquid environment or a non-liquid environment. The motor may be sealed in that it may be capable of being operated in a liquid environment without modification, or the motor may be non-sealed such that it would not be capable of operating in a liquid environment without modification. For example, it may be desired that a particular electromagnetic motor not be operated within a liquid-filled environment. In such an arrangement, a liquid or fluid tight barrier may be used between the electromagnetic motor and the ultrasound transducer array. Motor dimensions are selected to be compatible with the desired application, for example, to fit within components sized for a particular intra-cavity or intravascular clinical application. For example in ICE applications, the components contained therein, such as the motor, may fit in a volume of about 1 mm to about 4 mm in diameter.
In a still further aspect, the catheter may comprise a steerable or pre-curved catheter segment located near the distal end of the outer tubular body and the deflectable member may comprise an ultrasound transducer array. Further, the catheter may include a lumen (e.g., for delivering an interventional device) extending from the proximal end to a point distal thereto.
In another aspect, the catheter may comprise an outer tubular body having a wall, a proximal end and a distal end. The catheter may further include a lumen (e.g., for delivering an interventional device) extending through the outer tubular body from the proximal end to a port located distal to the proximal end. The catheter may further include a first electrical conductor portion comprising a plurality of interconnected electrical conductors arranged side-by-side with electrically non-conductive material therebetween. The first electrical conductor portion may extend from the proximal end to the distal end. The catheter may further include a second electrical conductor portion electrically interconnected to the first electrical conductor portion at the distal end. The second electrical conductor portion may comprise a plurality of electrical conductors. The catheter may further include a deflectable member located at the distal end. The second electrical conductor portion may be electrically interconnected to the deflectable member and may be bendable in response to deflection of the deflectable member.
In another aspect, the catheter may comprise an outer tubular body having a wall, a proximal end and a distal end. The catheter may further include a lumen (e.g., for delivering an interventional device or agent delivery device) extending through the outer tubular body from the proximal end to a port located distal to the proximal end. The catheter may further include a deflectable member, at least a portion of which is permanently located outside of the outer tubular body at the distal end, selectively deflectable relative to the outer tubular body and distal to the port. In an embodiment, the catheter may further include a hinge located at the distal end where the deflectable member may be supportably interconnected to the hinge. In such an embodiment, the deflectable member may be selectively deflectable relative to the outer tubular body about a hinge axis defined by the hinge.
Numerous aspects described hereinabove comprise a selectively deflectable imaging device disposed at a distal end of an outer tubular body of a catheter. Additional aspects of the present invention may include deflectable members in place of such deflectable imaging devices. Such deflectable members may include imaging devices, diagnostic devices, therapeutic devices, or any combination thereof.
The various features discussed above in relation to each aforementioned aspect may be utilized by any of the aforementioned aspects. Additional aspects and corresponding advantages will be apparent to those skilled in the art upon consideration of the further description that follows.
The use herein of terms such as first, second, third, etc. are used herein to distinguish between elements in a particular embodiment and should be interpreted in light of the particular embodiment.
The catheter 1000 includes a catheter body 1001. The catheter body 1001 is an elongate member with a proximal end and a distal end. The catheter body 1001 may comprise, for example, a shaft (e.g., a solid shaft, a shaft comprising at least one lumen), an outer tubular body, an inner tubular body, or any combination thereof. The catheter body 1001 may include a steerable segment or a plurality of steerable segments along a length thereof. At least portions of the catheter body 1001 may be flexible and capable of bending to follow the contours of passageways within the body of the patient into which it is being inserted.
The catheter body 1001 may optionally include a lumen. Such a lumen may run all or a portion of the length of the catheter body 1001 and may have a port at or near the distal end of the catheter body 1001. Such a lumen may be used to convey a device and/or material therethrough (e.g., deliver a device and/or material to or near to the distal end of the catheter body 1001). In another example, the lumen may be used to deliver a therapeutic device, an imaging device, an implantable device, a dosage of a therapeutic compound, or any combination thereof to or proximate to the distal end of the catheter body 1001. In another example, the lumen may be used to retrieve a device such as a vena cava filter.
The catheter 1000 includes a deflectable member 1002. As illustrated, the deflectable member 1002 may be disposed at the distal end of the catheter body 1001. The deflectable member may be operable to deflect relative to the distal end of the catheter body 1001. For example, the deflectable member 1001 may be operable for positioning across a range of angles relative to the longitudinal axis of the catheter body 1001 at the distal end of the catheter body 1001. The deflectable member 1002 may have a smooth, rounded exterior profile that may help in reducing thrombus formation and/or tissue damage as the deflectable member 1002 is moved (e.g., advanced, retracted, rotated, repositioned, deflected) within the body.
The deflectable member 1002 is interconnected to the catheter body 1001 through an interconnection 1003 that allows the deflectable member 1002 to deflect relative to the distal end of the catheter body 1001. The interconnection 1003 may comprise a, component or material that connects two objects, typically allowing relative rotation between them, e.g., one or more joints or hinges of appropriate type such as a living hinge or an ideal hinge (which may be referred to as an real hinge). Such hinges may be made of flexible material or of components that may move relative to each other. Such hinges may include a pintle. In the case of a single ideal hinge, the deflectable member 1002 may rotate relative to the catheter body 1001 about a fixed axis of rotation. In the case of a single living hinge, the deflectable member 1002 may rotate relative to the catheter body 1001 about a substantially fixed axis of rotation. The interconnection 1003 may comprise linking members, such as bars pivotably interconnected to the catheter body 1001 and/or deflectable member 1002, to control the motion of the deflectable member 1002 relative to the catheter body 1001. The interconnection 1003 may comprise a biasing member (e.g., a spring) to bias the deflectable member 1002 to a desired position relative to the catheter body 1001 (e.g., aligned with the distal end of the catheter body 1001). The interconnection 1003 may comprise a shape memory material.
The deflection of the deflectable member 1002 may be controlled by a deflection control member 1004. The deflection control member 1004 may be disposed along the catheter body 1001 at a point outside of the body (e.g., at the proximal end of the catheter body 1001). The deflection control member 1004 may, for example, include a knob, slider, or any other appropriate device interconnected to one or more control wires that are in turn interconnected to the deflectable member 1002, such that rotation of the knob or movement of the slider produces a corresponding deflection of the deflectable member 1002. In such an embodiment, the control wire or wires may run along the catheter body 1001 from the deflection control member 1004 to the deflectable member 1002. In another embodiment, the deflection control member 1004 may be an electronic controller operable to control an electrically deflected deflectable member 1002. In such an embodiment, electrical conductors for deflection control may run along the catheter body 1001 from the deflection control member 1004 to the components for deflecting the deflectable member 1002.
The deflectable member 1002 may optionally include a motor 1005 for driving a driven member 1006. The motor 1005 may be operatively interconnected to the driven member 1006 to move the driven member 1006. For example, the motor 1005 may be operable to drive the driven member 1006 such that the driven member 1006 pivotally reciprocates about a pivot axis. The motor 1005 may be any appropriate device, including the devices discussed herein, for creating motion that may be used to drive the driven member 1006. Although
The driven member 1006 may be an electrical device such as an imaging, diagnostic and/or therapeutic device. The driven member 1006 may include a transducer array. The driven member 1006 may include an ultrasound transducer. The driven member 1006 may include an ultrasound transducer array, such as a one dimensional array or a two dimensional array. In an example, the driven member 1006 may include a one dimensional ultrasound transducer array that may be reciprocally pivoted by the motor 1005 such that an imaging plane of the one dimensional ultrasound transducer array is swept through a volume, thus enabling the generation of 3D images and 4D image sequences.
The catheter body 1001 may include one or more members that run along the length of the catheter body 1001. For example, the catheter body 1001 may include electrical conductors running along the length of the catheter body 1001 that electrically connect the motor 1005 and the driven member 1006 to componentry located elsewhere on or apart from the catheter such as motor controllers, ultrasound transducer controllers, and ultrasound imaging equipment. The catheter body 1001 may include control wires or other control devices to steer a steerable portion of the catheter body 1001 and/or control the deflection of the deflectable member 1002.
The catheter 1000 may, for example, be employed for imaging a heart. In an exemplary use, the catheter 1000 may be introduced into the body and positioned within the heart. While within the heart, the motor 1005 may reciprocally drive the driven member 1006 in the form of an ultrasound transducer array to generate 3D images and/or 4D image sequences of the heart. Also while in the heart, the deflectable member 1002 may be deflected to reposition the field of view of the ultrasound transducer array.
Certain embodiments of the deflectable member 1002 may be deflectable such that a minimum presentation width of the catheter 1000 is less than about 3 cm. The minimum presentation width for a catheter is equal to the minimum diameter of a straight tube in which the entire catheter may fit (without kinking) while a tip of the catheter is oriented perpendicular to the axis of the tube. The concept of the minimum presentation width is illustrated in
The detailed description that follows in relation to
Although not mentioned, the embodiments of
An ultrasound transducer array built into a catheter presents unique design challenges. Two critical points include, for example, the resolution in the image plane and the ability to align that image plane with an interventional device.
The resolution in the imaging plane of an ultrasound array can be approximated by the following equation:
Lateral resolution=Constant*wavelength*Image Depth/Aperture Length
For catheters being described here, the wavelength is typically in the range of 0.2 mm (at 7.5 MHz). The constant is in the range of 2.0. The ratio of (Image Depth/Aperture Length) is a critical parameter. For ultrasound imaging in the range of 5-10 MHz for catheters presented here, acceptable resolution in the imaging plane can be achieved when this ratio is in the range of 10 or less.
For imaging with a catheter in the major vessels and the heart, it is desirable to image at depths of 70 to 100 mm. Catheters used in the heart and major vessels are typically 3 to 4 mm in diameter or smaller. Thus while conceptually a transducer array can be made of arbitrary size and placed at any position within the catheter body, this model shows that transducer arrays that readily fit within the catheter structure do not have sufficient width for acceptable imaging.
The ultrasound image plane produced by the array placed on the catheter typically has a narrow width normally referred to as the out of plane image width. For objects to be seen in the ultrasound image, it is important that they be in this image plane. When a flexible/bendable catheter is placed in a major vessel or heart, the image plane can be aligned to some degree. It is desirable to guide a second device placed in the body with the ultrasound image, but doing so requires placing that second device in the plane of the ultrasound image. If the imaging array and the interventional device are both on flexible/bendable catheters that are inserted into the body, it is extremely difficult to orient one interventional device into the ultrasound image plane of the imaging catheter.
Certain embodiments of the present invention utilize an ultrasound image to guide an interventional device. To accomplish this, a large enough aperture is needed to produce an image of acceptable resolution while being able to place the device in a known position that is stable relative to the imaging array and/or to be able to align and/or register the interventional device to the ultrasound image plane.
In certain implementations, the aperture length of the ultrasound array may be larger than the maximum cross dimension of the catheter. In certain implementations, the aperture length of the ultrasound array may be much larger (2 to 3 times larger) than the diameter of the catheter. This large transducer, however, may fit within the 3 to 4 mm maximum diameter of the catheter to be inserted into the body. Once in the body, the imaging array is deployed out of the catheter body leaving space to pass an interventional device through that same catheter that will then be located in a known position relative to the imaging array. In certain arrangements, the imaging array may be deployed in a way so that the interventional device can be readily kept within the ultrasound image plane.
The catheter may be configured for delivery through a skin puncture at a remote vascular access site (e.g., vessel in the leg). Through this vascular access site, the catheter may be introduced into regions of the cardiovascular system such as the inferior vena cava, heart chambers, abdominal aorta, and thoracic aorta.
Positioning the catheter in these anatomic locations provides a conduit for conveyance of devices or therapy to and/or from specific target tissues or structures. One example of this includes bedside delivery of inferior vena cava filters in patients for whom transport to the catheterization laboratory is either high risk or otherwise undesirable. The catheter with the ultrasound transducer array allows the clinician to not only identify the correct anatomical location for placement of the inferior vena cava filter, but also provides a lumen through which the vena cava filter can be delivered under direct ultrasound visualization. Both location identification and delivery of a device can occur without withdrawal or exchange of the catheter and/or imaging device. In addition, post-delivery visualization of the device allows the clinician to verify placement location and function(s) prior to removal of the catheter.
Another application of such a catheter is as a conduit through which ablation catheters can be delivered within the atria of the heart. Although ultrasound imaging catheters are utilized today in many of these cardiac ablation procedures, it is very difficult to achieve proper orientation of the ablation catheters and ultrasound catheter so as to attain adequate visualization of the ablation site. The catheter described herein provides a lumen through which the ablation catheter can be directed and the position of the ablation catheter tip monitored under direct ultrasound visualization. As described, the coaxial registration of this catheter and other interventional devices and therapy delivery systems provides the means by which direct visualization and control can be achieved.
Turning back now to the figures,
Operation of the catheter 1 can be understood with reference to
Deflectable can include 1) “actively deflectable” meaning that, in embodiments with an array, the array or catheter portion containing the array can be moved by remote application of force (e.g., electrical (e.g., wired or wireless), mechanical, hydraulic, pneumatic, magnetic, etc.), transmission of that force by various means including pull wires, hydraulic lines, air lines, magnetic coupling, or electrical conductors; and 2) “passively deflectable” meaning that, in embodiments with an array, the array or catheter portion containing the array when in the resting, unstrained condition, tends to be in alignment with the catheter longitudinal axis and may be moved by local forces imparted by the introduction of interventional device 11.
In certain embodiments, the ultrasound transducer array may be deflected up to 90 degrees from the longitudinal axis of the catheter, as shown in
With reference to
“Steerable” is defined as the ability to direct the orientation of a portion of a catheter distal to a steerable segment at an angle with respect to a portion of a catheter proximal to the steerable segment. “Steering” may include any known method of steering that may be utilized to direct the orientation of the portion of the catheter distal to the steerable segment at an angle with respect to the portion of the catheter proximal to the steerable segment, including methods that utilize more than one steerable segment. Such methods may include, without limitation, use of remote application of force (e.g., electrical (e.g., wired or wireless), mechanical, hydraulic, pneumatic, magnetic, etc.) with transmission of that force by various means including pull and/or push wires, hydraulic lines, air lines, magnetic coupling, or electrical conductors including without limitation transmission by manipulation of push and/or pull wires, filaments, tubes, and/or cables. In addition, the catheter body may be constructed to have segments with differing flexibility or compression properties from the other segments of the catheter body. In an embodiment having an inner tubular body and an outer tubular body, the outer tubular body may have one or more steerable segments with push/pull wires anchored to the distal end of the steerable segments and extending through one or more lumens of the outer tubular wall to attachment to the steering control in the handle. Steering of the outer tubular body may steer the inner tubular body as well. In a variation, the inner tubular body may be steerable and steering of the inner tubular body may steer the outer tubular body as well.
Steering with reference to
In a further embodiment,
As can be seen in
In various embodiments described herein, catheters may be provided having an ultrasound transducer array located near the distal end thereof. The catheter body may comprise a tube having a proximal end and a distal end. Moreover, the catheter may have at least one lumen extending from the proximal end to at least near the ultrasound transducer array. The catheter may comprise electrically conductive wires (e.g., a GORE™ Micro-Miniature Ribbon Cable) attached to the ultrasound transducer array and being imbedded in the catheter wall and helically extending from the ultrasound transducer array to the proximal end of the catheter.
Such a catheter is depicted, for example, in
The above catheter provides a means to electrically interface with an ultrasound probe at the distal end of a catheter while providing a working lumen to facilitate conveyance of a device and/or material (e.g., for delivery of interventional devices to the imaged area). The construction of the catheter utilizes the conductors both to power the array as well as to provide mechanical properties that enhance kink resistance and torqueability. The novel construction presented provides a means to package the conductors and necessary shielding in a thin wall, thus providing a sheath profile that is suited for interventional procedures, with an OD targeted at or below 14 French (Fr) and an ID targeted at above 8 Fr, thus facilitating delivery of typical ablation catheters, filter delivery systems, needles, and other common interventional devices designed for vascular and other procedures.
Furthermore, the user may insert an interventional device (e.g., a diagnostic device and/or therapeutic device) through an interventional device inlet 62. The user may then feed the interventional device through the catheter 50 to move the interventional device to the distal end 53 of the catheter 50. Electrical interconnections between an image processor and the deflectable member may be routed through an electronics port 60 and through the catheter body 54 as described below.
The tip 64 may have a cross section that corresponds to the cross section of the outer tubular body 79. For example, and as illustrated in
In an embodiment, such as the one illustrated in
The tip 64 may further include a feature to enable the catheter to track a guidewire. For example, as illustrated in
As noted, the deflectable member 52 may be deflectable relative to the outer tubular body 79. In this regard, the deflectable member 52 may be interconnected to one or more members to control the motion of the deflectable member 52 as it is being deflected. A tether 78 may interconnect the deflectable member 52 to the catheter body 54. The tether 78 may be anchored to the deflectable member 52 on one end and to the catheter body 54 on the other end. The tether 78 may be configured as a tensile member operable to prevent the anchor points from moving a distance away from each other greater than the length of the tether 78. In this regard, through the tether 78, the deflectable member 52 may be restrainably interconnected to the outer tubular body 79.
An inner tubular body 80 may be disposed within the outer tubular body 79. The inner tubular body 80 may include the lumen 82 passing through the length of the inner tubular body 80. The inner tubular body 80 may be movable relative to the outer tubular body 79. This movement may be actuated by movement of the slide 58 of
Deflection of the deflectable member 52 will now be discussed with reference to
The support 74 may comprise, for example, a shape memory material (e.g., a shape memory alloy such as Nitinol). The support 74 may further include a hinge portion 86. The hinge portion 86 may comprise one or more members interconnecting the tubular body interface portion 84 with a cradle portion 88. The hinge portion 86, as illustrated in
The hinge portion 86 may be shaped such that upon application of an actuation force, the hinge portion 86 elastically deforms along a predetermined path about a deflection axis 92. The predetermined path may be such that the tip 64 and the hinge portion 86 each are moved to a position where they do not interfere with an interventional device emerging from the distal end of the lumen 82. An imaging field of view of the ultrasound transducer array 68 may be substantially maintained in a position relative to the outer tubular body 79 when the interventional device is advanced through the port 81 at the distal end of the lumen 82 and into the field of view. As illustrated in
To deflect the deflectable member 52 relative to the outer tubular body 79, the inner tubular body 80 may be moved relative to the outer tubular body 79. Such relative movement is illustrated in
In an exemplary embodiment, a movement of the inner tubular body 80 of about 0.1 cm may result in the deflectable member 52 deflecting through an arc of about 9 degrees. In this regard, movement of the inner tubular body 80 of about 1 cm may result in the deflectable member 52 deflecting about 90 degrees. Thusly, the deflectable member 52 may be selectively deflected from a side-looking position to a forward-looking position. Intermediate positions of the deflectable member 52 may be achieved by moving the inner tubular body 80 a predeterminable distance. For example, in the current exemplary embodiment, the deflectable member 52 may be deflected 45 degrees from the side-looking position by moving the inner tubular body 80 about 0.5 cm relative to the outer tubular body 79 in the actuation direction 90. Other appropriate member geometries may be incorporated to produce other relationships between inner tubular body 80 and deflectable member 52 deflection. Moreover, deflections of greater than 90 degrees may be obtained (e.g., such that the deflectable member 52 is at least partially side-looking to a side of the catheter body 54 opposite from that illustrated in
The slide 58 and handle 56 may be configured such that substantially any relative motion of the slide 58 to the handle 56 results in a deflection of the deflectable member 52. In this regard, there may be substantially no dead zone of the slide 58 where slide 58 movement does not result in deflection of the deflectable member 52. Furthermore, the relationship between movement of the slide 58 (e.g., relative to the handle 56) and the amount of corresponding deflection of the deflectable member 52 may be substantially linear.
When the deflectable member 52 is deflected from the position illustrated in
When in a forward-looking position, the field of view of the ultrasound transducer array 68 may encompass an area in which an interventional device may be inserted through the lumen 82. In this regard, the ultrasound transducer array 68 may be operable to aid in the positioning and operation of the interventional device.
The deflectable member 52 may deflect about the deflection axis 92 (deflection axis 92 is aligned with the view of
The deflectable member 52 may deflect about the deflection axis 92 such that the ultrasound transducer array 68 is positioned proximate to the port 81. Such positioning, in conjunction with a small displacement arc 93, reduces the distance an interventional device must travel between emerging from the port 81 and entering the field of view of the ultrasound transducer array 68. For example, upon deflection of 90 degrees as shown in
As illustrated in
In an exemplary arrangement, the outer covering 94 may include a plurality of helically wound films. A first portion of the plurality of films may be wound in a first direction, and a second portion of the films may be wound in a second direction that is opposite from the first direction. Where each film of the plurality of films has a longitudinal modulus of at least about 1,000,000 psi (6,895 MPa) and a transverse modulus of at least about 20,000 psi (137.9 MPa), each film of the plurality of films may be wound about a central axis of the tubular body at an angle of less than about 20 degrees relative to the central axis of the tubular body 79.
Within the outer covering 94 may be disposed an outer low-dielectric constant layer 96. The outer low-dielectric constant layer 96 may reduce capacitance between the electrical interconnection member 104 and materials (e.g., blood) outside of the outer covering 94. The outer low-dielectric constant layer 96 may have a dielectric constant of less than about 2.2. In an embodiment, the outer low-dielectric constant layer 96 may be about 0.07-0.15 mm thick. In an embodiment, the outer low-dielectric constant layer 96 may comprise a porous material, such as ePTFE. The voids in the porous material may be filled with a low-dielectric material such as air.
In an exemplary arrangement, the combinative properties of the outer covering 94 and the outer low-dielectric constant layer 96 may include a maximum thickness of 0.005 inches (0.13 mm) and an elastic modulus of 34,500 psi (237.9 MPa). In this regard, the outer covering 94 and the outer low-dielectric constant layer 96 may be viewed as a single composite layer including two sub-layers (the outer covering 94 and the outer low-dielectric constant layer 96).
Moving toward the center of the outer tubular body 79, the next layer may be first tie layer 97. The first tie layer 97 may comprise a film material that may have a melt temperature that is lower then other components of the outer tubular body 79. During fabrication of the outer tubular body 79, the first tie layer 97 may be selectively melted to yield an interconnected structure. For example, selectively melting the first tie layer 97 may serve to secure the outer low-dielectric constant layer 96, the first tie layer 97, and a shield layer 98 (discussed below) to each other.
Moving toward the center of the outer tubular body 79, the next layer may be the shield layer 98. The shield layer 98 may be used to reduce electrical emissions from the outer tubular body 79. The shield layer 98 may be used to shield components internal to the shield layer 98 (e.g., the electrical interconnection member 104) from external electrical noise. The shield layer 98 may be in the form of a double served wire shield or braid. In an exemplary embodiment, the shield layer 98 may be about 0.05-0.08 mm thick. Moving toward the center of the outer tubular body 79, the next layer may be a second tie layer 100. The second tie layer 100 may comprise a film material that may have a melt temperature that is lower then other components of the outer tubular body 79. During fabrication of the outer tubular body 79, the second tie layer 100 may be selectively melted to yield an interconnected structure.
Interior to the second tie layer 100 may be the electrical interconnection member 104. The electrical interconnection member 104 may comprise a plurality of conductors arranged in a side-by-side fashion with an insulative (e.g., non-conductive) material between the conductors. The electrical interconnection member 104 may comprise one or more microminiature flat cables. The electrical interconnection member 104 may contain any appropriate number of conductors arranged in a side-by-side fashion. By way of example, the electrical interconnection member 104 may contain 32 or 64 conductors arranged in a side-by-side fashion. The electrical interconnection member 104 may be helically disposed within the outer tubular body 79. In this regard, the electrical interconnection member 104 may be helically disposed within the wall of the outer tubular body 79. The electrical interconnection member 104 may be helically disposed such that no part of the electrical interconnection member 104 overlies itself. The electrical interconnection member 104 may extend from the proximal end 55 of the catheter 50 to the distal end 53 of the outer tubular body 79. In an embodiment, the electrical interconnection member 104 may be disposed parallel to and along the central axis of the outer tubular body 79.
As illustrated in
An inner tie layer 102 may be disposed interior to the electrical interconnection member 104. The inner tie layer 102 may be configured similar to and serve a similar function as the second tie layer 100. The inner tie layer 102 may have a melting point of, for example, 160 degrees Celsius. Moving toward the center of the outer tubular body 79, the next layer may be an inner low-dielectric constant layer 106. The inner low-dielectric constant layer 106 may be configured similar to and serve a similar function as the outer low-dielectric constant layer 96.
The inner low-dielectric constant layer 106 may be operable to reduce capacitance between the electrical interconnection member 104 and materials (e.g., blood, interventional device) within the outer tubular body 79. Moving toward the center of the outer tubular body 79, the next layer may be an inner covering 108. The inner covering 108 may be configured similar to and serve a similar function as the outer covering 94. The inner covering 108 and the outer covering 94 may have a combined thickness of at most about 0.002 inches (0.05 mm). Moreover, the inner covering 108 and outer covering 94 may have a combined elastic modulus of at least about 345,000 psi (2,379 MPa). Combined, the inner covering 108 and the outer covering 94 may provide an elongation resistance such that a tensile load, applied to the inner covering 108 and the outer covering 94, of about 3 lbf (13 N) results in no more than a 1 percent elongation of the tubular body 79. In an arrangement, the tubular body 79 may provide an elongation resistance such that a tensile load, applied to the tubular body 79, of about 3 lbf (13 N) results in no more than a 1 percent elongation of the tubular body 79, and in such an arrangement at least about 80 percent of the elongation resistance may be provided by the inner covering 108 and outer covering 94.
The inner covering 108 and outer covering 94 may exhibit a substantially uniform tensile profile about their circumferences and along the length of the tubular body 79 when a tensile load is applied to the tubular body 79. Such a uniform response to an applied tensile load may, inter alia, help to reduce undesirable directional biasing of the catheter body 54 during positioning (e.g., insertion into a patient) and use (e.g., while deflecting the deflectable member 52).
As with the outer covering 94 and the outer low-dielectric constant layer 96, the inner low-dielectric constant layer 106 and the inner covering 108 may be viewed as sub-layers to a single composite layer.
The tie layers (first tie layer 97, second tie layer 100, and inner tie layer 102) may each have substantially the same melting point. In this regard, during construction, the catheter body 54 may be subjected to an elevated temperature that may melt each of the tie layers simultaneously and fix various layers of the catheter body 54 relative to each other. Alternatively, the tie layers may have different melting points allowing selective melting of one or two of the tie layers while leaving the other tie layer or tie layers unmelted. Accordingly, embodiments of catheter bodies 54 may comprise zero, one, two, three, or more tie layers that have been melted to secure various layers of the catheter body 54 to other layers of the catheter body 54.
The aforementioned layers (from the outer covering 94 through the inner covering 108) may each be fixed relative to each other. Together these layers may form the outer tubular body 79. Interior to these layers and movable relative to these layers may be the inner tubular body 80. The inner tubular body 80 may be disposed such that there is an amount of clearance between the outside surface of the inner tubular body 80 and the interior surface of the inner covering 108. The inner tubular body 80 may be a braid reinforced polyether block amide (e.g., the polyether block amide may comprise a PEBAX® material available from Arkema Inc., Philadelphia, Pa.) tube. The inner tubular body 80 may be reinforced with a braided or coiled reinforcing member. The inner tubular body 80 may possess a column strength adequate that it may be capable of translating a lateral motion of the slide 58 along the length of the inner tubular body 80 such that the deflectable member 52 may be actuated by the relative movement of the inner tubular body 80 where it interfaces with the support 74 at the tubular body interface portion 84. The inner tubular body 80 may also be operable to maintain the shape of the lumen 82 passing through the length of the inner tubular body 80 during deflection of the deflectable member 52. Accordingly, a user of the catheter 50 may be capable of selecting and controlling the amount of deflection of the deflectable member 52 through manipulation of the handle 56. The lumen 82 may have a center axis aligned with the center axis 91 of the outer tubular body 79.
To assist in reducing actuation forces (e.g., the force to move the inner tubular body 80 relative to the outer tubular body 79), the inner surface of the inner covering 108, the outer surface of the inner tubular body 80, or both may include a friction reduction layer. The friction reduction layer may be in the form of one or more lubricious coatings and/or additional layers.
In a variation of the embodiment illustrated in
In an exemplary embodiment, the catheter body 54 may have a capacitance of less than 2,000 picofarads. In an embodiment, the catheter body 54 may have a capacitance of about 1,600 picofarads. In the above-described embodiment of
The catheter body 54 may have a kink diameter (the diameter of bend in the catheter body 54 below which the catheter body 54 will kink) that is less than ten times the diameter of the catheter body 54. Such a configuration is appropriate for anatomical placement of the catheter body 54.
As used herein, the term “outer tubular body” refers to the outermost layer of a catheter body and all layers of that catheter body disposed to move with the outermost layer. For example, in the catheter body 54 as illustrated in
The various layers of the outer tubular body 79 described with reference to
Within the interconnect region 110, the electrically conductive portions (e.g., wires) of the electrical interconnection member 104 may be interconnected to electrically conductive portions (e.g., traces, conductive paths) of the flexboard 76. This electrical interconnection may be achieved by peeling back or removing some of the insulative material of the electrical interconnection member 104 and contacting the exposed electrically conductive portions to corresponding exposed electrically conductive portions on the flexboard 76. The end of the electrical interconnection member 104 and the exposed conductive portions of the electrical interconnection member 104 may be disposed at an angle relative to the width of the electrical interconnection member 104. In this regard, the pitch (e.g., the distance between the centers of the electrically conductive portions) between the exposed electrically conductive portions of the flexboard 76 may be greater than the pitch (as measured across the width) of the electrical interconnection member 104, while maintaining an electrical interconnection between each conductor of both the electrical interconnection member 104 and the flexboard 76.
As illustrated in
The flexing region 112 may be interconnected to an array interface region 114 of the flexboard 76 through which the electrically conductive paths of the electrical interconnection member 104 and the flexboard 76 may be electrically interconnected to individual transducers of the ultrasound transducer array 68.
As illustrated in
In an embodiment, the electrical interconnection member 104 may comprises two or more separate sets of conductors (e.g., two or more microminiature flat cables). In such an embodiment, each of the separate sets of conductors may be interconnected to the flexboard 76 in a manner similar to as illustrated in
The deflectable member 116 may be selectively deflectable. As shown in
The outer tubular body 118 may include a lumen 128 operable to allow an interventional device to pass therethrough. At least a portion of the deflectable member 116 may be permanently positioned distal to the distal end of with the outer tubular body 118. In an embodiment, the entirety of the deflectable member 116 may be permanently positioned distal to the distal end of the outer tubular body 118.
The deflectable member 116 may be deflectable relative to the outer tubular body 118. In this regard, the deflectable member 116 may be interconnected to one or more elongate members to control the motion of the deflectable member 116 as it is being deflected. The elongate member may take the form of a pull wire 130. The pull wire 130 may be a round wire. Alternatively, for example, the pull wire 130 may be rectangular in cross-section. For example, the pull wire may be rectangular in cross-section with a width-to-thickness ratio of about 5 to 1.
As with the catheter embodiment illustrated in
The outer tubular body 118 may include a distal portion 124. The distal portion 124 may comprise a plurality of wrapped layers disposed about a securement portion 133 (shown in
Deflection of the deflectable member 116 will now be discussed with reference to
To deflect the deflectable member 116 relative to the outer tubular body 118, the pull wire 130 may be moved relative to the outer tubular body 118. As shown in
Disposed interior to the outer low-dielectric constant layer 96 may be the shield layer 98. A first tie layer (not shown in
Moving toward the center of the outer tubular body 118, the next layer may be a coiled reinforcement layer 144. The coiled reinforcement layer 144 may, for example, comprise a stainless steel coil. In an exemplary embodiment, the coiled reinforcement layer 144 may be about 0.05-0.08 mm thick. Moving toward the center of the outer tubular body 118, the next layer may be an inner covering 146. The inner covering 146 may be configured similar to and serve a similar function as the outer covering 94. The lumen 128 may have a central axis aligned with the central axis of the outer tubular body 118.
As noted above, the wrapped layers of the distal portion 124 of the outer tubular body 118 may serve to secure the securement portion 133 of the support 126 to an inner portion of the outer tubular body 118. For example, each layer outboard of the electrical interconnection member 104 may be removed in the distal portion 124. Furthermore, the electrical interconnection member 104 may be electrically interconnected to the flexboard 122 proximal to the distal portion 124 in a manner similar to as described with reference to
The outer diameter of the outer tubular body 118 may, for example, be about 12.25 Fr. The inner diameter of the outer tubular body 118 may, for example, be about 8.4 Fr.
Further embodiments are shown in
As further demonstrated in
The next step 152 may be to obtain image data from the deflectable imaging device during at least a portion of the moving step. The obtaining step may be performed with the deflectable imaging device located in the first position. During the moving and obtaining steps, a position of the deflectable imaging device relative to the distal end of the catheter may be maintained. Thus the deflectable imaging device may be moved and images may be obtained without moving the deflectable imaging device relative to the distal end of the catheter. During the moving step, the catheter, and therefore the deflectable imaging device, may be rotated relative to its surroundings. Such rotation may allow the deflectable imaging device to obtain images in a plurality of different directions transverse to the path traveled by the catheter during the moving step.
The next step 154 may be to utilize the image data to determine when the catheter is located at the desired position. For example, the image data may indicate the position of the deflectable imaging device, and therefore the distal end of the catheter, relative to a landmark (e.g., an anatomical landmark).
The next step 156 may be to deflect the deflectable imaging device from the first position to a second position. The deflecting step may follow the moving step. The deflectable imaging device may be forward-looking in the second position. The deflectable imaging device may be angled at least about 45 degrees relative to a central axis of the catheter when in the second position. Optionally, after the deflecting step, the deflectable imaging device may be returned to the first position and the catheter repositioned (e.g., repeating the moving step 150, the obtaining step 152, and the utilizing step 154). Once repositioned, the deflecting step 156 may be repeated and the method may be continued.
In an embodiment, the catheter may comprise an outer tubular body and an activation device, each extending from a proximal end to the distal end of the catheter. In such an embodiment, the deflecting step may include translating a proximal end of at least one of the outer tubular body and actuation device relative to a proximal end of the other one of the outer tubular body and actuation device. The deflectable imaging device may be supportably interconnected by a hinge to one of the outer tubular body and the actuation device, and the deflecting step may further comprise applying a deflection force to the hinge in response to the translating step. Furthermore, the deflecting step may further include initiating the application of the deflection force to the hinge in response to the translating step. The deflection force may be applied and then maintained by manipulating a handle interconnected to the proximal end of the catheter. Moreover, the applying step may comprise communicating the deflection force by the actuation device from the proximal end to the distal end of the catheter in a balanced and distributed manner about a central axis of the outer tubular body.
The next step 158 may be to advance an interventional device through a port at the distal end of the catheter and into an imaging field of view of the deflectable imaging device in the second position. The imaging field of view may be maintained in substantially fixed registration to the distal end of the catheter during the advancing step.
After advancing and using the interventional device (e.g., to perform a procedure, to install or retrieve a device, to make a measurement), the interventional device may be withdrawn through the port. The deflectable imaging device may then be returned to the first position. The return to the first position may be facilitated by an elastic deformation quality of the hinge. For example, the hinge may be biased toward positioning the deflectable imaging device in the first position. As such, when the deflectable imaging device is in the second position and the deflection force is removed, the deflectable imaging device may return to the first position. After withdrawal of the interventional device through the port (and optionally from the entire catheter) and return of the deflectable imaging device to the first position, the catheter may then be repositioned and/or removed.
As with the supports 74, 126 above, the supports described below may be made from any appropriate material, such as, for example, a shape memory material (e.g., Nitinol). Any appropriate tubular body discussed herein may be configured to include any suitable electrical configuration member. For example, where appropriate in the embodiments discussed below, the outer tubular bodies may contain electrical interconnection members similar to the electrical interconnection member 104 of
The support 74 of
Returning briefly to
To pivot the array support 250 relative to the inner and outer tubular bodies 244, 246, the inner tubular body 244 is moved along a common central axis relative to the outer tubular body 246. As illustrated in
The catheter 242 may also include a tip portion (not shown) that may be molded over the array support 250, an ultrasound imaging array, and any other appropriate components. Any appropriate electrical interconnection, such as those described herein, may be used with the catheter 242 of
In a variation of the embodiment of
To pivot the support portion 266 and its attached ultrasound imaging array 272 relative to the inner and outer tubular bodies 262, 264, the inner tubular body 262 is moved along a common central axis relative to the outer tubular body 264. As illustrated in
The catheter 260 may also include a tip portion (not shown) that may be molded over the support portion 266 and the ultrasound imaging array 272, and any other appropriate components. Any appropriate electrical interconnection, such as those described herein, may be used with the catheter 260 of
In a first variation of the embodiment of
The notch 302 may be configured to accept the densified portion 310 of the tether 304 such that the densified portion 310 is hooked on to the notch 302. Accordingly, the notch 302 may be configured such that its opening is generally further away from the outer tubular body 298 than the deepest portion of the notch 302 where the tether 304 may tend to occupy. Since the tether 304 will generally be in tension during deflection of the cradle portion 306, the tether 304 may tend to remain within the notch 302. A tip 312 may be formed over the cradle portion 306 and as such may aid in retention of the densified portion 310 within the notch 302. As noted, the support 300 may be configured similarly to the support 74 of FIGS. 5B-5D and as such may be actuated in a similar manner (e.g., by motion of the inner tubular body 296 relative to the outer tubular body 298 and a corresponding bend of the support 300 as shown in
While being inserted into a patient, the catheter 340 may be configured as shown in
In use, the catheter 362 may be inserted into a patient with the tip portion 368 disposed within the outer tubular body 364. Once the catheter 362 is in a desired position, the inner member 366 may be advanced relative to the outer tubular body 364 and/or the outer tubular body 364 may be retracted such that the tip portion 368 is no longer disposed within the outer tubular body 364. Accordingly, the tip portion 368 may move to the deployed position (illustrated in
Where appropriate, other embodiments described herein may include ultrasound imaging arrays that may be displaced into rearward-looking positions. These may be in place of or in addition to the disclosed ultrasound imaging arrays. For example, the embodiment illustrated in
In use, the catheter 380 may be inserted into a patient with the tip 384 temporarily bonded to the tubular body 382. While in the position illustrated in
The first control cable 406 may be attached to a first half rod 412. The second control cable 408 may be attached to a second half rod 414. The half rods 412, 414 may each be half cylinders configured such that when proximate to each other, they form a cylinder about equal in diameter to the inner diameter of the tubular body 404. The half rods 412, 414 may be made of flexible and/or lubricious material (e.g., PTFE) and may be operable to flex along with the tubular body 404 (e.g., while the catheter 402 is disposed within the patient). The half rods 412, 414 may be disposed proximate to the distal end of the catheter 402, and the second half rod 414 may be fixed relative to the tubular body 404, while the first half rod 412 remains movable relative to the tubular body 404. Moreover, an actuator (not shown), such as a flat wire or the like, may be attached to the first half rod 412 and run along the length of the tubular body 404 to enable a user move the first half rod 412 relative to the second half rod 414 and thus manipulate the position of the ultrasound imaging array 410.
The repositioning of the ultrasound imaging array 410 has been described as a result of moving the first half rod 412 while the second half rod 414 remains stationary relative to the tubular body 404. In alternate embodiments, the ultrasound imaging array 410 may be repositioned by moving the second half rod 414 while the first half rod 412 remains stationary or by moving both the first half rod 412 and the second half rod 414 simultaneously, sequentially or a combination of simultaneously and sequentially.
In the embodiment of
During insertion into a patient, the catheter 418 may be arranged as in
In a variation of the embodiment of
In another variation of the embodiment of
During insertion into a patient, the catheter 436 may be arranged as in
During insertion into a patient, the catheter 458 may be arranged as in
It will be appreciated that the hinges 446, 468 of
During insertion into a patient, the catheter 484, with an appropriately configured tip (not shown), may be arranged as in
It will be appreciated that, where appropriate, the electrical interconnection members described herein that are disposed between tubular bodies and ultrasound imaging arrays that move relative to those tubular bodies, may be configured to additionally serve as biasing members (such as described above with respect to
The hinge portion 512 may, as illustrated in
An ultrasound imaging array 516 may be interconnected to the support portion 510. A first end of a first tether 518 may be interconnected to a distal end of the inner tubular body 508 and a second end of the first tether 518 may be interconnected to a proximal end of the support portion 510. A first end of a second tether 520 may be interconnected to the inner tubular body 508 and a second end of the second tether 520 may be interconnected to a distal end of the support portion 510. The second tether may be threaded through a through hole 522 in the outer tubular body 506.
To pivot the support portion 510 and its attached ultrasound imaging array 516 from the position illustrated in
The catheter 504 may also include a tip portion (not shown) that may be molded over the support portion 510, the ultrasound imaging array 516, and/or any other appropriate components. Any appropriate electrical interconnection, such as those described herein, may be used with the catheter 504 of
With the support portion 510 aligned with the tubular portion 514 as shown in
To pivot the support portion 510 and its attached ultrasound imaging array 516 from the position illustrated in
The catheter 526 may also include a tip portion (not shown) that may be molded over the support portion 510, the ultrasound imaging array 516, and/or any other appropriate components. Any appropriate electrical interconnection, such as those described herein, may be used with the catheter 526 of
The catheter 534 includes a tether 546 disposed between a distal portion of the hinge portion 544 and the inner tubular body 538. The tether 546 may be at least partially wrapped about and anchored to the outer circumference of the inner tubular body 538. The tether 546 may be in the form of a cord like member able to transmit tensile forces along its length and to conformally wrap about the inner tubular body 538.
To pivot the support portion 540 and its attached ultrasound imaging array 542 from the position illustrated in
To return the support portion 540 to the position illustrated in
The catheter 534 may also include any appropriate electrical interconnection to the ultrasound imaging array 542, including appropriate connection schemes described herein. In a variation of the embodiment of
In use, the catheter 534 may be inserted into a patient with the support portion 540 aligned with the outer tubular body 536. Once the catheter 534 is in a desired position, the inner tubular body 538 may be rotated relative to the outer tubular body to allow the hinge portion 544 to move the support portion 540 to a desired angle relative to the longitudinal axis of the catheter 534. An interventional device (not shown) may be advanced through the lumen within the inner tubular body 538.
To pivot the ultrasound imaging array 562 from the position illustrated in
The catheter 552 may also include any appropriate electrical interconnection to the ultrasound imaging array 562, including appropriate connection schemes described herein. For example, an electrical interconnection member may be disposed along the arm 560 and may electrically interconnect the ultrasound imaging array 562 to an electrical interconnection member disposed within a wall of the tubular body 554. A tip (not shown) may be molded over the ultrasound imaging array 562.
The catheter 552 may be further operable to deploy the ultrasound imaging array 562 to the position illustrated in
To pivot the ultrasound imaging array 562 from the position illustrated in
To move the imaging arrays 586a, 586b from the positions illustrated in
The catheter 576 may also include any appropriate electrical interconnection to the imaging arrays 586a, 586b, including appropriate connection schemes described herein. For example, an electrical interconnection member may be disposed along the outer tubular body 578 and first and second rigid portions 588, 590.
The imaging arrays 598a and 598b may be pivoted in a manner similar to as discussed above with reference to
The imaging arrays 586a, 586b, 598a, 598b of
The relative rotation between the distal portion 616 and the proximal portion 618 may be achieved in any appropriate manner. For example, the catheter 604 may include an inner tubular body (not shown) similar to the inner tubular body of catheter 576 of
To move the ultrasound imaging array 630 from the position illustrated in
Catheter 642 also includes a second ultrasound imaging array 650 that is oriented to image in an at least partially rearward-looking direction. Ultrasound imaging array 650 may be in addition to the ultrasound imaging array 630 or it may be the only imaging array of catheter 642.
The catheters 624, 642 may also include any appropriate electrical interconnection to the ultrasound imaging array 630, including appropriate connection schemes described herein. For example, electrical interconnection members may be disposed along the inner tubular bodies 628, 646.
In addition to deployment of an ultrasound imaging array to obtain images of an area of interest, deployment of ultrasound imaging arrays may also aid in positioning a lumen (e.g., for introduction of an interventional device or other appropriate device). For example, the deployment of the ultrasound transducer array 37 of
The configuration of spring element 652 may, for example, be disposed within the sidewall of the catheter body of the embodiment of
In still another example, spring elements similar to the spring element 652 (e.g., but with two springs) may be deployed within the outer tubular bodies 578, 596 of the catheters 576, 594 of
During insertion of the catheter 662 into a patient, the catheter 662 may be configured as illustrated in
When it is desired to obtain images of a region distal to the tip 674, the collapsible lumen 668 may be pulled proximally relative to the outer tubular body 664. The result may be for the distal end of the catheter 662 to bend (upward when in the orientation shown in
When it is desired to insert an interventional device 676 into the patient, the interventional device 676 may be advanced distally through the collapsible lumen 668. As the interventional device 676 is advanced through the side port 670, the opening of the side port 670 may be displaced such that it is in line with the central cavity of the outer tubular body 664. As the interventional device 676 is advanced through the section of the collapsible lumen 668 external to the outer tubular body 664, that portion of the collapsible lumen 668 may also be moved such that it is aligned with the central cavity of the outer tubular body 664. As the interventional device 676 is advanced through the end port 672, the end port 672 may also be moved such that it too is aligned with the central cavity of the outer tubular body 664 and the section of the collapsible lumen 668 external to the outer tubular body 664. As the interventional device 676 is advanced, the ultrasound imaging array 666 may be displaced perpendicularly (e.g., downward when in the orientation illustrated in
Upon retraction of the interventional device 676, the catheter 662 may be returned to an aligned position (e.g., the configuration of
The catheter 662 may also include any appropriate electrical interconnection to the ultrasound imaging array 666, including appropriate connection schemes described herein. For example, electrical interconnection members may be disposed along the outer tubular body 664.
The hinge portion 710 may allow the tip support portion 708 to pivot about the hinge portion 710 relative to the inner tubular body 704. An electrical interconnection member 712 may electrically interconnect to the ultrasound imaging array 706. The electrical interconnection member 712 is connected to a distal end of the ultrasound imaging array 706. The electrical interconnection member 712 may be bonded or otherwise fixed to a portion 714 of the tip support portion 708 on an opposite side of the tip support from the ultrasound imaging array 706. The electrical interconnection member 712 may include a loop 716 between the connection to the ultrasound imaging array 706 and the portion 714. The portion 714, by virtue of its fixed position relative to the tip support portion 708 may serve as a strain relief preventing strain associated with pivoting of the ultrasound imaging array 706 from being translated to the loop 716 and array 706 through the electrical interconnection member 712. A tether portion 718 of the electrical interconnection member 712 may be disposed between the bonded portion 714 and the point where the electrical interconnection member 712 enters into the outer tubular body 702. The tether portion 718 may be an unmodified portion of the electrical interconnection member 712 or it may be modified (e.g., structurally reinforced) to accommodate additional forces due to its serving as a tether. The tip support portion 708 and the ultrasound imaging array 706 may be encased or otherwise disposed within a tip (not shown).
During insertion into a patient, the catheter 700 may be arranged as in
During insertion into a patient, the catheter 720 may be arranged as in
During insertion into a patient, the catheter 740 may be arranged as in
As desired, the tip portion 746 that includes the ultrasound imaging array 748 may be pivoted relative to the tubular body 742 to a forward-looking position where the ultrasound imaging array 748 may be used to generate images of a volume distal to the catheter 740. To pivot the tip portion 746, a first step may be to feed a portion of the wire 752 through the wire feed hole 756 to form a snare 758 (a loop of the wire 752 external to the tip portion 746) illustrated in
The catheter 740 may also include any appropriate electrical interconnection to the ultrasound imaging array 748, including appropriate connection schemes described herein. For example, electrical interconnection members may be disposed along the tubular body 742 and the intermediate portion 750.
The electrical interconnection member 788 may further include an array connection portion 794 configured to electrically connect to an ultrasound imaging array (not shown in
An alternate embodiment of the electrical interconnection member 788 may be configured without the array connection portion 794. Such a configuration may utilize “flying leads” where each conductor of the non-bonded portion 792 remains electrically interconnected to the helically disposed portion 790 on one end and unconnected on the other end. These unconnected flying leads may then, for example, be individually bonded to corresponding conductors on an ultrasound imaging array.
In embodiments described herein wherein a movable elongate member (e.g., pull wire) is employed to cause a deflection of an ultrasound imaging array, the elongate member is generally routed along one side of a catheter body. In a variation of such embodiments, the elongate member may be configured such that a first portion of it is disposed along a first side of the catheter body, and a second portion of the elongate member is disposed along a second side of the catheter body. For example,
Turning to
L=x/sin(θ) Equation 1
Furthermore, the angle (θ) is related to (D), (L) and (g) as follows:
tan(θ)=(π(D))/(z(L+g)) Equation 2
Where (z) is the number of unique electrical interconnection members 852 wound about the substrate 850 (in the catheter of
Turning to
(L+gm)/L=R/(R−(D/2)) Equation 3
Plugging the values for (L) (0.222 inches (5.64 mm)) and (D) (0.130 inches (3.3 mm)) into Equation 3 and using a minimum desired bend radius (R) of 1.0 inch (25.4 mm), yields a minimum gap (gm) of 0.015 inches (0.38 mm). Accordingly, the gap (g) of 0.030 inches (0.76 mm) used above in Equations 1 and 2 exceeds the minimum gap (gm) of 0.015 inches (0.38 mm) for a bend radius (R) of 1.0 inch (25.4 mm) from Equation 3. Therefore the gap (g) of 0.030 (0.76 mm) inches should not result in subsequent coils of the electrical interconnection member 852 coming into contact with each other when the catheter is bent to a bend radius (R) of 1.0 inch (25.4 mm).
The catheter tip 5301 may be disposed between the distal end 5303 and a proximal end 5304 of the catheter tip 5301. The catheter tip 5301 may include a catheter tip case 5305. The catheter tip case 5305 may be a relatively rigid (as compared to the catheter shaft 5302) member housing a motor 5306 and a transducer array 5307, both of which are discussed below. Alternatively, as noted below, a portion of the catheter tip case 5305 may be steerable and/or flexible. The catheter tip 5301 may include a central axis 5308.
The catheter shaft 5302 may be operable to be guided into the patient. The catheter shaft 5302 may use any appropriate guidance method such as, but not limited to, a set of control wires and associated controls. In this regard, the catheter shaft 5302 may be steerable. The catheter shaft 5302 may be flexible and therefore be operable to be guided through and follow contours of the structure of the patient, such as the contours of the vasculature system. The catheter shaft 5302 may include an outer layer 5309 and an inner layer 5310. The outer layer 5309 may be constructed from a single layer of material or it may be constructed from a plurality of distinct layers of materials. Similarly, the inner layer 5310 may be constructed from a single layer of material or it may be constructed from a plurality of distinct layers of materials. The inner layer 5310 includes a distal section 5338 that is disposed at the distal end of the inner layer 5315. The distal section 5338 may be an integral part of the inner layer 5310. Alternatively, the distal section 5338 may be separate from the remainder of the inner layer 5310 prior to assembly of the catheter probe assembly 5300, and during assembly the distal section 5338 may be interconnected to the remainder of the inner layer 5310. The inner layer 5310, the outer layer 5309, or both may be configured and/or reinforced to mitigate unwanted catheter rotation due to reciprocal motion described herein and/or to generally increase the strength of the catheter probe assembly. Such reinforcement may take the form of a braided member disposed on or adjacent to the inner layer 5310 and/or the outer layer 5309.
An electrical interconnection member 5311 may be disposed within the catheter probe assembly 5300. The electrical interconnection member 5311 may be comprised of a first portion 5312 and a second portion 5313. The second portion 5313 of the electrical interconnection member 5311 is illustrated in cross-section in
A distal end 5315 of the inner layer 5310 may be sealed along its outer perimeter using a sealing material 5316. The sealing material 5316 may be disposed as illustrated between the outer perimeter of the distal end 5315 of the inner layer 5310 and an inner surface of the catheter tip case 5305. In another embodiment, the outer layer 5309 of the catheter shaft 5302 may extend to or beyond the distal end 5315 of the inner layer 5310 and in such an embodiment, the sealing material 5316 may be disposed between the outer perimeter of the distal end 5315 of the inner layer 5310 and an inner surface of the outer layer 5309. Alternatively, the region 5314 between the inner layer 5310 and the outer layer 5309 may, in addition to containing the helically disposed second portion 5313 of the electrical interconnection member 5311, be partially or completely filled with the sealing material 5316. The sealing material 5316 may include any appropriate material such as, for example, a thermoset or thermoplastic material or expanded polytetrafluoroethylene (ePTFE). The second portion 5313 of the electrical interconnection member 5311 may extend along an entire length of the catheter shaft 5302 from the proximal end 5304 of the catheter tip 5301 to an imaging system (not shown). In this regard, the electrical interconnection member 5311 may operatively connect the catheter tip 5301 with the imaging system.
An enclosed volume 5317 may be defined by the catheter tip case 5305, an end portion of the inner layer 5310 of the catheter shaft 5302 and an enclosed volume end wall 5318. The enclosed volume end wall 5318 may be sealably disposed within the inner layer 5310 near to the distal end 5315 of the inner layer 5310. The enclosed volume 5317 may also be sealed by the sealing material 5316 as discussed above.
The enclosed volume 5317 may be fluid-filled and sealed. The fluid may be a biocompatible oil selected, inter alia, for its acoustical properties. For example, the fluid may be chosen to match or approximate the acoustic impedance and/or the acoustic velocity of fluid within the region of the body that is to be imaged. The enclosed volume 5317 may be sealed such that the fluid within the enclosed volume 5317 is substantially unable to leak out of the enclosed volume 5317. Furthermore, the enclosed volume 5317 may be sealed to substantially prevent gasses (e.g., air) from entering into the enclosed volume 5317.
The catheter probe assembly 5300 may be filled using any appropriate method. During filling, the catheter probe assembly 5300 and the fluid may be at known temperatures to beneficially control the volume of fluid introduced and the size of the enclosed volume 5317. In one exemplary filling method, the catheter tip case 5305 may include a sealable port 5336. Gasses within the enclosed volume may be drawn by vacuum out of the enclosed volume 5317 through the sealable port 5336. Then, the fluid may be introduced through the sealable port 5336 until the desired amount of fluid is within the enclosed volume 5317. The sealable port 5336 may then be sealed. In another example, the catheter probe assembly 5300 may include the sealable port 5336 at the distal end 5303 and a sealable port 5337 at the proximal end 5304. The sealable port 5337 may be disposed along the enclosed volume proximal end wall 5318. One of the ports 5337, 5338 may be used as an inlet port for the fluid while the other port 5337, 5338 may be used as an outlet port for displaced gasses. In this regard, as fluid is passed through the inlet port, gasses may escape (or be pulled from using a vacuum) from the enclosed volume 5317 through the outlet port. Once the desired volume of fluid is within the enclosed volume 5317, the ports 5337, 5338 may be sealed. In the above described filling methods, a measured amount of fluid may be removed from the enclosed volume 5317 after it has been completely filled. The amount of fluid removed may correspond to the desired amount of expansion of a bellows member 5320 (described below).
The catheter tip 5301 may include a check valve (not shown) that may be operable to allow fluid to flow out of the enclosed volume 5317 if the pressure differential between the enclosed volume 5317 and the surrounding environment exceeds a predetermined level. The check valve may be in the form of a slit valve disposed along the catheter tip case 5305. In this regard, the check valve may operate to relieve excess pressure that may be created during the filling process, thereby reducing the possibility of the catheter probe assembly 5300 bursting during the filling procedure. Once the enclosed volume is filled, the check valve may be permanently sealed. For example, a clamp may be placed over the check valve to seal the check valve.
The internal portion 5319 of the catheter shaft 5302 may be sealably separated from the enclosed volume 5317. The internal portion 5319 of the catheter shaft 5302 may be disposed within an interior volume of the inner layer 5310. The internal portion 5319 of the catheter shaft 5302 may contain air and may be vented such that the pressure within the internal portion 5319 of the catheter shaft 5302 is equal or close to the local atmosphere pressure in which the catheter probe assembly 5300 is situated. Such venting may be accomplished through a dedicated vent mechanism (such as an opening in the catheter shaft 5302 at a point outside of the body of the patient) between the internal portion 5319 of the catheter shaft 5302 and the local atmosphere.
As may be appreciated, if the enclosed volume 5317 was completely surrounded by substantially rigid members and filled with fluid, temperature variations of the catheter probe assembly 5300 could result in unwanted changes in pressure within the enclosed volume 5317. For example, in such a configuration, if the catheter probe assembly 5300 was exposed to elevated temperatures, the pressure of the fluid within the enclosed volume 5317 may increase; possibly causing some of the fluid to leak out of the enclosed volume 5317. Likewise for example, if the catheter probe assembly 5300 was exposed to reduced temperatures, the pressure of the fluid within the enclosed volume 5317 may decrease, possibly causing some air or other fluid to leak into the enclosed volume 5317. Accordingly, it may be beneficial to prevent or reduce pressure variations within the enclosed volume 5317 relative to the environmental conditions in which the catheter probe assembly 5300 is located.
To assist in equalizing pressure between the fluid within the enclosed volume 5317 and surrounding conditions, the bellows member 5320 may be incorporated into the catheter probe assembly 5300. The bellows member 5320 may be a generally flexible member that is collapsible and expansible in response to volumetric changes in the fluid within the enclosed volume 5317, such as volumetric changes as a result of temperature changes. The bellows member 5320 may be configured to define an internal volume and have a single opening. The single opening may be an open end 5321 of the bellows member 5320 such that the open end 5321 may be disposed along the end wall 5318 and oriented such that the internal volume of the bellows member 5320 is in communication with the internal portion 5319 of the catheter shaft 5302. The remaining portion of the bellows member 5320 may be disposed within the enclosed volume 5317 and may include a closed end portion.
The initial configuration of the bellows member 5320 may be selected such that the bellows member 5320 is operable to compensate for (e.g., equalize pressure between the enclosed volume 5317 and the internal portion 5319 of the catheter shaft 5302) temperature variations across the operational range of temperatures for the catheter probe assembly 5300. Moreover, the bellows member 5320 may be configured to compensate for temperature variations greater than the operational range of temperatures for catheter probe assembly 5300, such as temperature variations that may be seen during catheter probe assembly 5300 storage and/or transportation. The bellows member 5320 may be curved or otherwise shaped to avoid other internal components within the enclosed volume 5317.
At the maximum fluid temperature for which the bellows member 5320 is designed to compensate, the bellows member 5320 may be totally collapsed or close to being totally collapsed. In this regard, the expansion of the fluid within the enclosed volume 5317 may not result in a pressure increase within the enclosed volume 5317 since the bellows member 5320 collapse may compensate for the expansion of the fluid. At the minimum fluid temperature for which the bellows member 5320 is designed to compensate, the bellows member 5320 may be expanded at or near its expansion limit. In this regard, the volumetric contraction of the fluid within the enclosed volume 5317 may not result in a pressure decrease within the enclosed volume 5317 since the bellows member 5320 expansion may compensate for the contraction of the fluid. Furthermore, by positioning the bellows member 5320 in the enclosed volume 5317, it is protected from movement of the catheter shaft 5302.
Although the bellows member 5320 is illustrated as having a cross dimension considerably smaller than a cross dimension of the inner layer of the catheter shaft 5310, the bellows member 5320 may be considerably larger. In this regard, the bellows member 5320 may have a cross dimension approaching that of the inner layer of the catheter shaft 5310. It will be appreciated that such a bellows member may be relatively less flexible than the bellows member 5320 illustrated in
In conjunction with, or in place of, the bellows member 5320, a portion of the sidewall of the catheter tip case 5305 (e.g., a portion an end wall 5339 of the catheter tip case 5305 and/or a portion of the sidewall of the of the catheter tip case 5305 proximate to the first portion of the electrical interconnect member 5312) may be configured such that the portion performs a function similar to that of the bellows member 5320 described above. For example, the portion may be pliable and may flex inward if the fluid and catheter probe assembly 5300 become cooler and outward if the fluid and catheter probe assembly 5300 become warmer, thereby accommodating temperature related volume changes of the fluid.
In an embodiment, the bellows member 5320, or at least a distal portion thereof, may be elastically-deformable. In particular, the bellows member 5320 may be operable to stretch or elastically expand beyond a neutral state (e.g., a state where there is no pressure differential between the inside of the bellows member 5320 and the outside of the bellows member 5320) in reaction to a pressure differential between the enclosed volume 5317 and the interior of the catheter 5319 where the pressure within the interior of the catheter 5319 is greater than the pressure within the enclosed volume 5317. Such stretching or elastic expansion may accommodate greater pressure differentials than would be attainable with a similarly sized bellows member 5320 that was substantially incapable of stretching or elastically expanding. Furthermore, such a stretchable or elastically expandable bellows member 5320 may result in a catheter probe assembly 5300 that is capable of tolerating temperature variations greater than the operational range of temperatures for the catheter probe assembly 5300, such as temperature variations that may be seen during catheter probe assembly 5300 storage and/or transportation. Such a stretchable or elastically expandable bellows member 5320 may be capable of withstanding a greater range of fluid volumes (e.g., the catheter probe assembly 5300 with a stretchable or elastically expandable bellows member 5320 may be more tolerant of a wider range of ambient temperatures, extending particularly the low temperature range where the fluid typically contracts more than the catheter tip case 5305). Such a stretchable or elastically expandable bellows member 5320 may be silicone based and may be produced using, for example, a liquid transfer molding process.
In one embodiment, a resilient, elastically-deformable bellows member 5320 may be provided so that in a neutral state the bellows member 5320 automatically assumes an initial configuration. Such initial configuration may correspond with a preformed configuration (e.g. a bulbous, dropper-shaped configuration), except as spatially restricted by other rigid componentry (e.g., bubble trap 5322 and/or enclosed volume proximal end wall 5318). In turn, the bellows member 5320 may collapse and automatically expand and stretch relative to such initial configuration in response to pressure variations.
The catheter probe assembly may include a bubble-trap 5322, shown in cross section in
The bubble-trap 5322 may include a recess defined by a distal-facing concave surface 5323. Furthermore, a distal portion of the enclosed volume 5317 is defined as the portion of the enclosed volume 5317 distal to the bubble-trap 5322. Correspondingly, a proximal portion of the enclosed volume 5317 is defined as the portion of the enclosed volume 5317 proximal to the bubble-trap 5322. The bubble-trap 5322 may include an aperture 5324 that fluidly interconnects the distal portion to the proximal portion. The aperture 5324 may be disposed at or near the most proximal portion of the distal facing concave surface 5323.
During the life cycle of the catheter probe assembly 5300, bubbles may be formed in or enter into the enclosed volume 5317. The bubble-trap 5322 may be operable to trap these bubbles in the proximal portion of the enclosed volume 5317. For example, during normal operation of the catheter probe assembly 5300 the catheter probe assembly may be disposed in a variety of attitudes including attitudes where the distal end 5303 of the catheter probe assembly 5300 is facing downward. When the catheter probe assembly 5300 is in a downward facing attitude, a bubble within the distal portion may tend to naturally flow upward. Upon coming into contact with the concave face 5323, the bubble may continue to rise until it reaches the aperture 5324. The bubble may then pass through the aperture 5324, moving from the distal portion to the proximal portion. Once the bubble is in the proximal portion and the catheter probe assembly 5300 is placed in an attitude where the distal portion is facing upward, the bubble-trap 5322 will tend to direct any rising bubbles in the proximal portion away from the aperture 5324. Following the slope of the proximal surface of the bubble-trap 5322, the bubbles will tend to migrate to a trap region 5325 and be trapped therein.
The bubble-trap 5322 is beneficial since bubbles present between the transducer array 5307 and an acoustic window 5326 of the case 5305 may produce unwanted image artifacts when the catheter probe assembly 5300 is used to generate an image of an image volume 5327. This is due to the differing acoustical properties of an air bubble versus the acoustical properties of the fluid within the enclosed volume 5317. By keeping bubbles that may form during the lifetime of the catheter probe assembly 5300 away from the transducer array 5307, the operational life of the catheter probe assembly 5300 may be increased. In this regard, bubbles that may form within the enclosed volume 5317 or enter into the enclosed volume 5317 may not lead to a degradation of the images created using the catheter probe assembly 5300.
Prior to insertion of the catheter probe assembly 5300 into a patient, a user (e.g., a physician or technician) may manipulate the catheter probe assembly 5300 in a manner to help move any bubbles that may be present within the enclosed volume 5317 into the volume proximal to the bubble trap 5322. For example, the user may dispose the catheter probe assembly 5300 in an attitude where the distal end 5303 is pointing downward to allow bubbles within the enclosed volume 5317 to move upward into the volume proximal to the bubble trap 5322 thus trapping the bubbles. In another example, the user may grasp the catheter probe assembly 5300 at a point proximal to the catheter tip 5301 and swing the catheter tip 5301 around to impart centrifugal force on the fluid within the enclosed volume 5317 thereby causing the fluid to move toward the distal end 5303 and any bubbles within the fluid to move towards the proximal end 5304. In addition, the catheter probe assembly 5300 may be packaged such that the distal end 5303 is pointing downward so that any bubbles within the enclosed volume 5317 may migrate to the proximal end 5304 of the catheter tip 5301 while the catheter probe assembly 5300 is in storage or is being transported prior to use.
In another example, the catheter probe assembly 5300 may be packaged, shipped and stored in an unfilled state, and prior to use a user may fill the catheter probe assembly 5300 with a fluid. For example, the user may insert a needle of a syringe into the sealable port 5336 and inject a fluid (e.g., saline or bubble-free saline) into the catheter probe assembly 5300 to fill the catheter probe assembly 5300. The user may then manipulate the catheter probe assembly 5300 in any of the manners described above to help move any bubbles that may be present within the enclosed volume 5317 into the volume proximal to the bubble trap 5322. Such systems for packaging, shipping, storing and filling (both pre-filled and filled by the user) may be used by appropriate fluid filled arrangement discussed herein.
A filter may be disposed across the aperture 5324. The filter may be configured such that gasses (e.g., air) may pass through the filter while liquid (e.g., oil, saline) may not be able to pass through the filter. Such a configuration may allow air bubbles to pass from the distal end of the enclosed volume 5317 (the portion of the enclosed volume to the right of the bubble trap 5322 in
The catheter probe assembly 5300 includes the transducer array 5307 and an array backing 5328. The transducer array 5307 may comprise an array of a plurality of individual transducer elements that may each be electrically connected to the ultrasound imaging apparatus via a signal connection and a ground connection. The transducer array 5307 may be a one-dimensional array that includes a single row of individual transducer elements. The transducer array 5307 may be a two-dimensional array that includes individual transducer elements arranged, for example, in multiple columns and multiple rows. Ground connections of the entire transducer array 5307 may be aggregated and may be electrically connected to the ultrasound imaging apparatus through a single ground connection. The transducer array 5307 may be a mechanically active layer operable to convert electrical energy to mechanical (e.g., acoustic) energy and/or convert mechanical energy into electrical energy. For example, the transducer array 5307 may comprise piezoelectric elements. For example, the transducer array 5307 may be operable to convert electrical signals from the ultrasound imaging apparatus into ultrasonic acoustic energy. Furthermore, the transducer array 5307 may be operable to convert received ultrasonic acoustic energy into electrical signals.
The transducer array may include a cylindrical enclosure disposed about the array 5307 and array backing 5328. The cylindrical enclosure may reciprocally pivot along with the array 5307 and array backing 5328. The cylindrical enclosure may be constructed of a material that has an acoustic speed similar to blood or other body fluid in which the catheter probe assembly 5300 is to be inserted. The cylindrical enclosure may be sized such that a gap exists between the outer diameter of the cylindrical enclosure and the inner diameter of the case 5305 and acoustic window 5326. The gap may be sized such that capillary forces draw the fluid into, and keep the fluid within, the gap. The fluid may be the aforementioned oil, saline, blood (e.g., where the enclosed volume 5317 is open to its surroundings), or any other appropriate fluid. In one embodiment, the fluid may be placed into the enclosed volume 5317 at the time the catheter probe assembly 5300 is manufactured. In a variation, the fluid may be added at the time of use of the catheter probe assembly 5300. In another embodiment, a high viscosity non-water soluble couplant may be used in place of the above discussed fluid. The couplant may be positioned between the outer diameter of the cylindrical enclosure and the inner diameter of the case 5305. The couplant may be selected such that any escape of the couplant into a patient would not be unacceptably injurious. The couplant may be a grease, such as a silicone grease, Krytox™ (available from E. I. Du Pont De Nemours and Company, Wilmington, Del., U.S.A.), or any other appropriate high viscosity non-water soluble couplant.
To generate an ultrasound image, the ultrasound imaging apparatus may send electrical signals to the transducer array 5307 which in turn may convert the electrical energy to ultrasonic acoustic energy that may be emitted toward the image volume 5327. Structure within the image volume 5327 may reflect a portion of the acoustic energy back toward the transducer array 5307. The reflected acoustic energy may be converted to electrical signals by the transducer array 5307. The electrical signals may be sent to the ultrasound imaging apparatus where they may be processed and an image of the image volume 5327 may be generated.
Generally, the transducer array 5307 is operable to transmit ultrasonic energy through the acoustic window 5326 of the catheter tip case 5305. In the catheter probe assembly 5300, the acoustic window 5326 forms part of the catheter tip case 5305 along a portion of the circumference of the case along a portion of the length of the case.
As shown in
In general, the images generated by the catheter probe assembly 5300 may be of a subject (e.g., internal structure of a patient) within the image volume 5327. The image volume 5327 extends outwardly from the catheter probe assembly 5300 perpendicular to the transducer array 5307. The entire image volume 5327 may be scanned by the transducer array 5307. The plurality of ultrasonic transducers may be disposed along the central axis 5308 and may be operable to scan an image plane with a width along the central axis 5308 and a depth perpendicular to the transducer array 5307. The transducer array 5307 may be disposed on a mechanism operable to reciprocally pivot the transducer array 5307 about the central axis 5308 such that the image plane is swept about the central axis 5308 to form the image volume as shown in
As noted above, the enclosed volume 5317 may be fluid-filled. The fluid may act to acoustically couple the transducer array 5307 to the acoustic window 5326 of the catheter tip case 5305. In this regard, the material of the acoustic window 5326 may be selected to correspond to the acoustic impedance and/or the acoustic velocity of the fluid of the body of the patient in the region where the catheter tip 5301 is to be disposed during imaging.
The transducer array 5307 may be interconnected to an output shaft 5329 of the motor 5306 at a proximal end of the transducer array 5307. Furthermore, the transducer array 5307 may be supported on a distal end of the transducer array 5307 by a pivot 5330. As illustrated in
The motor 5306 may be disposed within the enclosed volume 5317. The motor 5306 may be an electrically powered motor operable to rotate the output shaft 5329 in both clockwise and counterclockwise directions. In this regard, the motor 5306 may be operable to reciprocally pivot the output shaft 5329 of the motor 5306 and therefore reciprocally pivot the transducer array 5307 interconnected to the output shaft 5329.
The motor 5306 may have an outer portion that has an outer diameter that is smaller than the inner diameter of the catheter tip case 5305 in the region of the catheter tip case 5305 where the motor 5306 is disposed. The outer portion of the motor 5306 may be fixedly mounted to the inner surface of the catheter tip case 5305 by one or more motor mounts 5331. The motor mounts 5331 may, for example, be comprised of beads of adhesive. The motor mounts 5331 may be disposed between the motor 5306 and inner surface of the catheter tip case 5305 in locations chosen to avoid interference with moving members (discussed below) associated with the reciprocal motion of the transducer array 5307. Motor mounts 5331 may be disposed along the distal end of the outer portion of the motor 5306. Motor mounts 5331 may also be disposed along the proximal end of the outer portion of the motor 5306 such as, for example, along the proximal end of the outer portion of the motor 5306 on the side of the motor 5306 opposite from the side visible in
When output shaft 5329 position is known, the corresponding position of the transducer array 5307 will be known. Output shaft 5329 position may be tracked in any appropriate manner, such as through the use of an encoder and/or a magnetic position sensor. Output shaft 5329 position may also be tracked through the use of hard stops limiting the motion of the transducer array 5307. Such hard stops (not shown) may limit the range through which the transducer array 5307 may reciprocally pivot. By driving the motor 5306 in a clockwise or counterclockwise direction for a specific period of time, it may be assumed that the motor 5306 has driven the transducer array 5307 against one of the hard stops and therefore the position of the transducer array 5307 may be known.
Electrical interconnections to the motor 5306 from the ultrasound imaging apparatus may be achieved through a dedicated set of electrical interconnections (e.g., wires) separate from the electrical interconnection member 5311. Alternatively, electrical interconnections to the motor 5306 may be made using a portion of the conductors of the electrical interconnection member 5311. Where a dedicated set of electrical interconnections are used to communicate with and/or drive the motor 5306, such interconnections may be run from the motor 5306 to the ultrasound imaging apparatus in any appropriate manner including, for example, through the interior 5319 of the catheter shaft 5302 and/or through the gap 5314. Furthermore, electrical interconnections from the ultrasound imaging apparatus to other components, such as thermocouples, other sensors, or other members that may be disposed within the catheter tip 5301, may be achieved through a dedicated set of electrical interconnections or they may be made using a portion of the conductors of the electrical interconnection member 5311.
The electrical interconnection member 5311 may electrically interconnect the transducer array 5307 with the ultrasound imaging apparatus. The electrical interconnection member 5311 may be a multi-conductor cable comprising of a plurality of conductors arranged side-by-side with electrically nonconductive material between the conductors. The electrical interconnection member 5311 may be ribbon shaped. For example, the electrical interconnection member 5311 may comprise one or more GORE™ Micro-Miniature Ribbon Cables. For example, the electrical interconnection member 5311 may include 64 separate conductors.
The electrical interconnection member 5311 may be anchored such that a portion of it is fixed relative to the catheter tip case 5305. As noted above, the second portion 5313 of the electrical interconnection member 5311 may be secured between the inner layer 5310 and outer layer 5309 of the catheter shaft 5302. Within the enclosed volume 5317, a first end 5332 of the first portion 5312 of the electrical interconnection member 5311 may be secured to the inner surface of the catheter tip case 5305. In this regard, the securing of the first end 5332 may be configured such that the transition from a secured portion of the electrical interconnection member 5311 to a free floating portion may be disposed perpendicular to the orientation of the conductors (e.g., across the width of the electrical interconnection member 5311) at the first end 5332. In another embodiment, the electrical interconnection member may be secured to the inner surface of the case by virtue of its securement between the inner layer 5310 and outer layer 5309 of the catheter shaft 5302. In such an embodiment, the transition from secured to free floating may not be oriented perpendicular to the conductors of the electrical interconnection member 5311. Any appropriate method of anchoring the electrical interconnection member 5311 to the catheter tip case 5305 may be used. For example, adhesive may be used.
Since during scanning the transducer array 5307 may be pivoted about the central axis 5308 relative to the catheter tip case 5305, the electrical interconnection member 5311 must be operable to maintain an electrical connection to the transducer array 5307 while the transducer array 5307 is pivoting relative to the catheter tip case 5305 to which the electrical interconnection member 5311 is fixed at the first end 5332. This may be achieved by coiling the first portion 5312 of the electrical interconnection member 5311 within the enclosed volume 5317. The first end 5332 of the coil may be anchored as discussed. A second end 5333 of the coil may be anchored to an interconnection support 5334 that pivots along with the transducer array 5307 about the central axis 5308. Where the electrical interconnection member 5311 is ribbon shaped, the first portion 5312 of the electrical interconnection member 5311 may be disposed such that a top or bottom side of the ribbon faces and wraps about the central axis 5308.
The electrical interconnection member 5311 may include ground and base layers. The ground and base layers may be configured differently than the other conductors of the electrical interconnection member 5311. For example, the ground layer may be in the form of a plane extending across the width of the electrical interconnection member 5311 and extending along the entire length of the electrical interconnection member 5311. Along the first portion of the electrical interconnection member 5312, the ground layer and/or the base layer may be separated from the remainder of the first portion of the electrical interconnection member 5312. Accordingly, the ground layer and/or base layer may be in the form of separate conductors (not shown) between the first end 5332 and the interconnection support 5334. Such an arrangement may result in a more flexible structure than that illustrated in
The first portion of the electrical interconnection member 5312 disposed within the enclosed volume 5317 may include additional layers of insulation relative to the second portion 5313. Such additional layers may provide protection against the fluid occupying the enclosed volume and/or such additional layers may provide protection against wear due to the first portion of the electrical interconnection member 5312 contacting other components (e.g., the case 5305). The additional layers may, for example, be in the form of one or more coatings and/or laminates.
The portion of the case 5305 that surrounds the enclosed volume 5317 in the region of the first portion of the electrical interconnection member 5312 may be structurally reinforced to resist kinking. Such reinforcement may be in the form of additional layers laminated to the inner and/or outer surface of the case 5305 or in the form of a structural support member secured to the case 5305.
In an embodiment, the first portion 5312 of the electrical interconnection member 5311 may include a total of about three revolutions about the central axis 5308. The total length of the catheter tip case 5305 may be selected to accommodate the number of revolutions needed for the first portion 5312 of the electrical interconnection member 5311. The total number of helical revolutions for the first portion 5312 of the electrical interconnection member 5311 may be determined based at least partially on desired coil expansion and contraction during pivotal movement, the desired level of counteracting torque imparted on the motor 5306 by the first portion 5312 during reciprocal movement, and the desired overall length of the catheter tip case 5305. Within the enclosed volume 5317, the first portion 5312 of the electrical interconnection member 5311 may be helically disposed such that there is a clearance between the outer diameter of the helix of the first portion 5312 and the inner surface of the catheter tip case 5305 as shown in
The helically disposed first portion 5312 of the electrical interconnection member 5311 may be disposed such that a volume within the helically disposed first portion 5312 may contain a tube or other component with a lumen therethrough or other appropriate component. Such lumens may accommodate any appropriate use such as, for example, catheter insertion, drug delivery, device retrieval, and/or guidewire tracking. For example, a tube with a lumen therethrough may be disposed within the helically disposed first portion 5312. Such a tube may extend form the proximal end of the catheter probe assembly 5300, pass through the enclosed volume end wall 5318 (in embodiments including the enclosed volume end wall 5318) and past the bubble trap 5322 (in embodiments including the bubble trap 5322). In such an embodiment, the bubble trap 5322 may be offset from the central axis 5308 to accommodate the tube. A portion of such a lumen may extend through at least a portion of the first portion of the electrical interconnection member 5312. In an embodiment, the tube and lumen may terminate in a side port. For example, the lumen may terminate at the sidewall of the case in the region where the helically disposed first portion 5312 is located.
The interconnection support 5334 may serve to support an interconnection between the electrical interconnection member 5311 and a flexboard 5335. As noted, the second end 5333 of the first portion 5312 of the electrical interconnection member 5311 may be fixedly secured to the interconnection support 5334. Additionally, the flexboard 5335 may be fixedly secured to the interconnection support 5334. The individual conductors of the electrical interconnection member 5311 may be electrically connected to individual conductors of the flexboard 5335. The flexboard 5335 may serve to electrically interconnect the electrical interconnection member 5311 to the transducer array 5307. Insulative material may be disposed over the electrical interconnections between the electrical interconnection member 5311 and the flexboard 5335. The insulative material may be laminated over the electrical interconnections. In another embodiment, a rigid interconnection member may be used in place of the above-described flexboard 5335. Such a rigid interconnection member may serve to electrically interconnect the electrical interconnection member 5311 to the transducer array 5307.
The interconnection support 5334 may be configured as a hollow cylinder operable to be disposed about the outer surface of the motor 5306. Alternatively, the interconnection support 5334 may be configured as a curved plane that is not wrapped completely around the outer surface of the motor 5306. In either circumstance (e.g., hollow cylinder or curved plane), the interconnection support 5334 may be operable to rotate about a portion of the outer surface of the motor 5306. In this regard, as the motor 5306 reciprocally pivots the transducer array 5307, the transducer array backing 5328 by virtue of its fixed connection to the transducer array 5307 will also reciprocally pivot. In turn, by virtue of its fixed connection to the transducer array backing 5328, the flexboard 5335 will also reciprocally pivot. In turn, by virtue of their fixed connection to the flexboard 5335, the interconnection support 5334 and the second end 5333 of first portion 5312 the electrical interconnection member 5311 will also reciprocally pivot along with the transducer array 5307.
In another embodiment, the interconnection support 5334 and the flexboard 5335 may be constructed from a single flexboard. In such an embodiment, the interconnection support 5334 portion of the single flexboard may be formed into at least a portion of a cylinder such that it may be disposed at least partially about the outer surface of the motor 5306.
Although the transducer array 5307 and associated members are generally described herein as being disposed in a catheter tip 5301 at a distal end 5303 of the catheter probe assembly 5300, other configurations are contemplated. For example, in another embodiment, the members disposed within the catheter tip 5301 may be disposed at a point along the catheter shaft 5302 that is offset from the distal end 5303 of the catheter probe assembly 5300. In this regard, portions of the catheter shaft 5302 and/or other components may be disposed distal to the catheter tip 5301.
In an alternate embodiment, the catheter tip case 5305 may be in the form of a protective cage disposed about the electrical interconnection member 5311, motor 5306, array 5307, and other appropriate components of the catheter probe assembly 5300. Such a cage may allow blood (or other bodily fluid) into the volume corresponding to the enclosed volume 5317 of the embodiment of
The catheter probe assembly 5344 may generally be sized and shaped for insertion into a patient and subsequent imaging of an internal portion of the patient. The catheter probe assembly 5344 may generally include the distal end 5303 and a proximal end (not shown). During imaging, the distal end 5303 of the catheter probe assembly 5344 may be disposed within the body of a patient. A catheter tip 5301′ may be disposed between the distal end 5303 and a proximal end 5304 of the catheter tip 5301′. The catheter tip 5301′ may include a catheter tip case 5305′. The catheter tip 5301′ may include a central axis 5308. An enclosed volume 5317′ may be defined by the catheter tip case 5305′ and the driveshaft 5343. The enclosed volume 5317′ may be fluid-filled and sealed.
The catheter shaft 5302′ may use any appropriate guidance method such as, but not limited to, a set of control wires and associated controls to actively steer the catheter shaft 5302′. The catheter shaft 5302′ may be flexible and therefore be operable to be guided through and follow contours of the structure of the patient, such as the contours of the vasculature system.
The catheter probe assembly 5344 includes the transducer array 5307 and the array backing 5328. Generally, the transducer array 5307 is operable to transmit ultrasonic energy through the acoustic window 5326 of the catheter tip case 5305′. In general, the images generated by the catheter probe assembly 5344 may be of a subject (e.g., internal structure of a patient) within an image volume 5327′.
The transducer array 5307 may be interconnected to the driveshaft 5343, and the driveshaft 5343 may be operable to reciprocally pivot the transducer array 5307 about the central axis 5308 such that the image plane is swept about the central axis 5308 to form the image volume 5327′ as shown in
The driveshaft 5343, and therefore the transducer array 5307 interconnected to the driveshaft 5343, may be reciprocated using any appropriate means. For example, the proximal end of the catheter probe assembly 5344 may include a motor capable of reciprocally driving the driveshaft 5343 in both clockwise and counterclockwise directions. In this regard, the motor may be operable to reciprocally pivot the driveshaft 5343 and therefore reciprocally pivot the transducer array 5307 interconnected to the driveshaft 5343.
When driveshaft 5343 position is known, the corresponding position of the transducer array 5307 will be known. Driveshaft 5343 position may be tracked in any appropriate manner, such as through the use of an encoder and/or a magnetic position sensor.
The electrical interconnection member 5311′ may electrically interconnect the transducer array 5307 with the ultrasound imaging apparatus. The electrical interconnection member 5311′ may be a multi-conductor cable comprising of a plurality of conductors arranged side-by-side with electrically nonconductive material between the conductors.
The electrical interconnection member 5311′ may be anchored such that a portion of it is fixed relative to the catheter tip case 5305′. As noted above, the second portion 5313 of the electrical interconnection member 5311′ may be secured to the catheter shaft 5302′. Within the enclosed volume 5317′, the third portion 5340 of the electrical interconnection member 5311′ may be secured to the inner surface of the catheter tip case 5305′. The third portion 5340 of the electrical interconnection member 5311′ may be secured to the catheter tip case 5305′ in a region corresponding to the position of the transducer array 5307. In this regard, the third portion 5340 of the electrical interconnection member 5311′ may be disposed such that it does not interfere with the reciprocal movement of the transducer array 5307. Any appropriate method of anchoring the electrical interconnection member 5311′ to the catheter tip case 5305′ may be used. For example, adhesive may be used.
The first portion 5342 of the electrical interconnection member 5311′ is operable to maintain an electrical connection to the transducer array 5307 while the transducer array 5307 is pivoting relative to the catheter tip case 5305′. This may be achieved by coiling the first portion 5342 of the electrical interconnection member 5311′ within the enclosed volume 5317′. One end of the first portion 5342 of the electrical interconnection member 5311′ may be anchored to the catheter tip case 5305′ at an anchor point 5341 that is distal to the transducer array 5307. The other end of the first portion 5342 of the electrical interconnection member 5311′ may be electrically interconnected to the array backing 5328 or to a flexboard or other electrical member (not shown) that is in turn electrically interconnected to the transducer array 5307. Where the electrical interconnection member 5311′ is ribbon shaped, the first portion 5342 of the electrical interconnection member 5311′ may be disposed such that a top or bottom side of the ribbon faces and wraps about the central axis 5308.
In an embodiment, the first portion 5342 of the electrical interconnection member 5311′ may include a total of about three revolutions about the central axis 5308. The total length of the catheter tip case 5305′ may be selected to accommodate the number of revolutions needed for the first portion 5342 of the electrical interconnection member 5311′.
A distal end of the driveshaft 5343 may be sealed along its outer perimeter using a sealing material 5316′. The sealing material 5316′ may be disposed as illustrated between the driveshaft 5343 and an inner surface of the catheter tip case 5305′. In another embodiment, the outer layer 5309′ of the catheter shaft 5302′ may extend to or beyond the distal end of the driveshaft 5343 and in such an embodiment, the sealing material 5316′ may be disposed between the driveshaft 5343 and an inner surface of the outer layer 5309′. The sealing material 5316′ may include any appropriate material and/or structure that allows relative rotational movement between the driveshaft 5343 and the outer layer 5309′ while substantially preventing the flow of fluid from the enclosed volume 5317′ past the sealing material 5316′. In another embodiment, the catheter shaft 5302′ may include an inner layer (similar to the inner layer 5310 of
The catheter probe assembly 5349 includes the transducer array 5307 and the array backing 5328. The transducer array 5307 may be interconnected to the driveshaft 5343, and the driveshaft 5343 may be operable to reciprocally pivot the transducer array 5307 about the central axis 5308 such that the image plane is swept about the central axis 5308 to form a three dimensional image volume 5327′ as shown in longitudinal cross section in
The electrical interconnection member 5311″ may electrically interconnect the transducer array 5307 with the ultrasound imaging apparatus (not shown). The electrical interconnection member 5311″ may include a portion including a multi-conductor cable comprising of a plurality of conductors arranged side-by-side with electrically nonconductive material between the conductors. The electrical interconnection member 5311″ may further include a portion including flexboard.
The electrical interconnection member 5311″ may be anchored such that a portion of it is fixed relative to the catheter tip case 5305″. As noted above, the second portion 5313 of the electrical interconnection member 5311″ may be secured to the catheter shaft 5302′. Within the enclosed volume 5317″, the third portion 5340 of the electrical interconnection member 5311″ may be secured to the inner surface of the catheter tip case 5305″. The third portion 5340 of the electrical interconnection member 5311″ may be secured to the catheter tip case 5305″ in a region corresponding to the position of the transducer array 5307. In this regard, the third portion 5340 of the electrical interconnection member 5311″ may be disposed such that it does not interfere with the reciprocal movement of the transducer array 5307. Any appropriate method of anchoring the third portion 5340 of the electrical interconnection member 5311″ to the catheter tip case 5305″ may be used. For example, adhesive may be used.
The first portion 5346 of the electrical interconnection member 5311″ is operable to maintain an electrical connection to the transducer array 5307 while the transducer array 5307 is pivoting relative to the catheter tip case 5305″. This may be achieved by coiling the first portion 5346 of the electrical interconnection member 5311″ within the enclosed volume 5317″. One end of the first portion 5346 of the electrical interconnection member 5311″ may be anchored to the catheter tip case 5305″ at an anchor point 5348 that is distal to the transducer array 5307. The other end of the first portion 5346 of the electrical interconnection member 5311″ may be electrically interconnected to a coil-to-backing portion 5347 of the electrical interconnection member 5311″. The coil-to-backing portion 5347 of the electrical interconnection member 5311″ may electrically interconnect the first portion 5346 of the electrical interconnection member 5311″ to the array backing 5328. The first portion 5346 of the electrical interconnection member 5311″ may have a generally flat cross-section and be disposed such that a top or bottom side of the first portion 5346 faces and wraps about the central axis 5308. The first portion 5346 of the electrical interconnection member 5311″ may be coiled in a “clock spring” arrangement where, as illustrated in
Similar to the embodiments of
In alternate configurations of the catheter probe assemblies 5344, 5349 of
Similar to as described above with reference to
In embodiments that include an enclosed volume within a catheter tip case, and embodiments where the catheter tip case is a cage that is open to the surrounding environment, the portion of the catheter tip case in the region of the helically coiled electrical interconnect (e.g., the first portion of the electrical interconnect 5312) may be steerable and/or flexible. In such a steerable and/or flexible configuration, the mechanical stresses due to steering and/or flexing on the electrical interconnect may be distributed over substantially the entire the helically coiled portion.
The ultrasound imaging system 5700 may further include a motor controller 5705 and an ultrasound console 5706. The motor controller 5705 may be operable to control a motor (embodiments of which are discussed below) that may be disposed within or interconnected to an ultrasound array within the deflectable member 5704. The ultrasound console 5706 may include an image processor, operable to process signals from the ultrasound array, and a display device, such as a monitor. The various functions described with reference to the motor controller 5705 and ultrasound console 5706 may be performed by a single component or by any appropriate number of discrete components.
Hinges described herein may rely on bending (e.g., living hinges) and/or a pivot (e.g., where the hinge includes a pin along a pivot axis) to define the relative motion between the deflectable member and the catheter body. Such hinges may include a non-tubular portion that allows the deflectable member and the catheter body to move relative to each other. Thus, a typical catheter steering arrangement that relies on one side of a tubular portion of the catheter being compressed to a greater degree than an opposing side of the tubular portion to achieve catheter bending is not typically considered a hinge.
The handle 5701 may be disposed at a proximal end 5711 of the catheter 5702. The user (e.g., clinician, technician, interventionalist) of the catheter 5702 may control the steering of the catheter body 5703, deflection of the deflectable member, and various other functions of the catheter 5702. In this regard, the handle 5701 includes two sliders 5707a, 5707b for steering the catheter body 5703. These sliders 5707a, 5707b may be interconnected to control wires such that when the sliders 5707a, 5707b are moved relative to each other, a portion of the catheter body 5703 may be curved in a controlled manner. Any other appropriate method of controlling control wires within the catheter body 5703 may be utilized. For example, the sliders could be replaced with alternative means of control such as turnable knobs or buttons. Any appropriate number of control wires within the catheter body 5703 may be utilized.
The handle 5701 further includes a deflection controller 5708. The deflection controller 5708 may be used to control the deflection of the deflectable member 5704 relative to the catheter body 5703. The illustrated deflection controller 5708 is in the form of a rotatable knob, where a rotation of the deflection controller 5708 will produce a corresponding deflection of the deflectable member 5704. Other configurations of the deflection controller 5708 are contemplated, including, for example, a slider similar to slider 5707a.
The handle 5701 may further include a motor activation button 5709 in embodiments of the ultrasound imaging system 5700 that include a motor within the deflectable member 5704. The motor activation button 5709 may be used to activate and/or deactivate the motor. The handle 5701 may further include a port 5710 in embodiments of the ultrasound imaging system 5700 that include a lumen within the catheter body 5703. The port 5710 is in communication with the lumen such that the lumen may be used for conveyance of a device and/or material.
In use, the user may hold the handle 5701 and manipulate one or both sliders 5707a, 5707b to steer the catheter body 5703 as the catheter 5702 is moved to a desired anatomical position. The handle 5701 and sliders 5707a, 5707b may be configured such that the position of the sliders 5707a, 5707b relative to the handle 5701 may be maintained, thereby maintaining or “locking” the selected position of the catheter body 5703. The deflection controller 5708 may then be used to deflect the deflectable member 5704 to a desired position. The handle 5701 and deflection controller 5708 may be configured such that the position of the deflection controller 5708 relative to the handle 5701 may be maintained, thereby maintaining or “locking” the selected deflection of the deflectable member 5704. In this regard, the deflectable member 5704 may be selectively deflectable, and the catheter body 5703 may be selectively steered, independently. Also, the deflection of the deflectable member 5704 may be selectively locked, and the shape of the catheter body 5703 may be selectively locked, independently. Such maintenance of position may at least partially be achieved by, for example, friction, detents, and/or any other appropriate means. The controls for the steering, deflection, and motor may all be independently operated and controlled by the user.
The ultrasound imaging system 5700 may be used to capture images of a three dimensional imaging volume 5714 and/or capture 3D images in real-time 5714. The deflectable member 5704 may be positioned by steering the catheter body 5703, articulating the deflectable member 5704, or by a combination of steering the catheter body 5703 and articulating the deflectable member 5704. Moreover, in embodiments with a lumen, the ultrasound imaging system 5700 may further be used, for example, to deliver devices and/or materials to a selected region or selected regions within a patient.
The catheter body 5703 may have at least one electrically conductive wire that exits the catheter proximal end 5711 through a port or other opening in the catheter body 5703 and is electrically connected to a transducer driver and image processor (e.g., within the ultrasound console 5706).
Furthermore, in embodiments with a lumen, the user may insert an interventional device (e.g., a diagnostic device and/or therapeutic device) or material, or retrieve a device and/or material through the port 5710. The user may then feed the interventional device through the catheter body 5703 to move the interventional device to the distal end 5712 of the catheter body 5703. Electrical interconnections between the ultrasound console 5706 and the deflectable member 5704 may be routed through an electronics port 5713 and through the catheter body 5703 as described above.
Catheter body 5703 incorporates a tube-in-tube design where an inner tube 5803 with a lumen 5804 is disposed within an outer tube 5802 and the inner tube 5803 is movable relative to the outer tube 5802 to control the deflection of the deflectable member 5704 (e.g., in a manner such as described with reference to
Alternatively, deflection of the deflectable member 5704 may be achieved by rotating the inner tube 5803 relative to the outer tube 5802 (e.g., in a manner such as described with reference to
Any other appropriate system for steering a catheter may be used in place of the 4-way steering illustrated in
Moreover, any other appropriate system for controlling the deflection of the deflectable members may be used in place of the tube-in-tube system or control wires 5903a, 5903b illustrated in
To deflect the deflectable member 5704 from the position of
The tether 6009 may be a discrete device whose primary function is to control the deflection of the deflectable member 5704. In another embodiment, the tether 6009 may be a flexboard or other multiple conductor component that, in addition to providing the tethering function, electrically interconnects components within the deflectable member 5704 (e.g., the transducer array 6002) with components within the catheter body 5703 (e.g., similar to electrical interconnection member 104 of
The hinge 6001 allows for relative hinged movement between a first portion 6010 of the hinge 6001 and a second portion 6011 of the hinge 6001. The two portions 6010, 6011 are joined along a hinge line 6012 and the deflectable member 5704 and inner tube 5803 move relative to each other about the hinge line 6012. In this regard, the relative motion between the deflectable member 5704 and inner tube 5803 is constrained by a non-tubular element. This is in contrast to the relative movement between different sections of the catheter body 5703 that may occur due to manipulation of the wires 5801a through 5801d to steer the catheter body 5703, where the relative motion between the different sections of the catheter body 5703 is constrained by a tubular element (e.g., by the compression and/or elongation of the outer tube 5802 and/or the inner tube 5803).
The hinge 6001 may be a unitary part, such as a single molded part. Moreover, the hinge 6001 may be in direct contact with, and fixedly connected to, the parts whose relative motion is desired to be constrained. In this regard, the first portion of the hinge 6010 may in direct contact with and fixedly connected to the inner tube 5803, while the second portion 6011 of the hinge 6010 may be in direct contact with and fixedly connected to the deflectable member 5704.
Embodiments of catheters described herein may also include one or more sensors for determining spatial positioning of the various components that may be inserted into a patient. For example, in concert with the imaging capability (e.g., 4D ultrasound imaging) of some of the embodiments, appropriately placed sensors may allow for the accurate identification of the spatial positions (e.g., within the cardiac chambers) of the various components (or portions thereof) of the embodiments. For example, relative positioning information provided by sensors facilitates the guidance of more complex ablation procedures, where electrical activity of the heart indicating treatment targets can be mapped to the catheter body and deflectable member positions.
An exemplary implementation of such sensors is illustrated in
The second portion 6011 of the living hinge 6001 may be semicircular in shape and may be configured to interface with a deflectable member, such as deflectable member 5704 of
The second portion 6011 may neck down to a predetermined thickness at the hinge line 6012 to achieve a desired hinge strength while also achieving a desired level of resistance to bending.
The living hinge 6001 may include a flattened region 6204 disposed along an outer surface of the living hinge 6001. The flattened region 6204 may be sized to accept a flexboard or other electrical interconnection member that may connect electrical conductors in a catheter body to electrical components in a deflectable member. The living hinge 6001 may include a ramp 6205 which may allow clearance for an electrical interconnection member to pass into an attached deflectable member while not presenting a sharp edge against which the electrical interconnection member could contact when the deflectable member is deflected.
As illustrated in
Accordingly, when the outer tube 6406 is moved proximally relative to the inner tube 6407 as illustrated in
In an alternate embodiment, the catheter body 6403 may be constructed from a single tube and the tether 6408 may be a push/pull wire activated by a user of the catheter 6400. In such an embodiment, a user would pull on the push/pull wire to pull the deflectable member 6404 in a positive direction as illustrated in
The catheter 6410 may have a total range of motion comparable to that illustrated with respect to catheter 6400 (e.g., at least about 200 degrees). The catheter 6410 may include a first actuation member 6417 and a second actuation member 6418 that may be used to deflect the deflectable member 6414. The first and second activation members 6417, 6418 may be in the form of wires. The first and second activation members 6417, 6418 may run along the length of the catheter body 6413 to a point where a user operating the catheter 6410 may be able to selectively pull either actuation member 6417, 6418 to control the deflection of the deflectable member 6414.
The first actuation member 6417 may be fixed to the deflectable member 6414 at a first anchor point 6419 that is disposed on a side of the deflectable member 6414 opposite from a front face of the transducer array 6415. In this regard, pulling on the first actuation member 6417 may cause the deflectable member 6414 to rotate in a positive direction (upward as shown in
An electrical interconnection member 6421 may pass through the centrally disposed living hinge 6411. The electrical interconnection member 6421 may, for example, include a flexboard.
As illustrated in
To achieve the 360 degrees of motion of the deflectable member 6504, the hinge 6501 may have a total length of at least the sum of one half the diameter of the deflectable member 6504 plus one half the diameter of the catheter body 6503 (e.g., about the distance between the center lines of the catheter body 6503 and the deflectable member 6504). In the illustrated embodiment, where the hinge 6501 is a single bendable member that generally bends uniformly as the deflectable member 6504 is deflected, the length of the hinge 6501 may be about one half the circumference of the deflectable member 6504 to allow the hinge 6501 to achieve the position illustrated in
In an alternative configuration illustrated in
In the embodiments illustrated in
The tether 6508 must possess an appropriate stiffness to enable it to push the deflectable member 6504 in the negative direction shown in
A sheath or other mechanical support (not shown) may be used to secure the deflectable member 6504 in the aligned position shown in
As illustrated in
The first actuation member 6606 may be fixed to the deflectable member 6604 on a side of the deflectable member 6604 opposite from a front face of the transducer array. In this regard, pulling on the first actuation member 6606 may cause the deflectable member 6604 to rotate in a positive direction (upward as shown in
The second actuation member 6607 may be fixed to the deflectable member 6604 on the same side of the deflectable member 6604 as the front face of the transducer array. In this regard, pulling on the second actuation member 6607 may cause the deflectable member 6604 to rotate in a negative direction (downward as shown in
The catheter 6600 includes an electrical interconnection member (not shown) to electrically interconnect the deflection member 6604 with conductors running along the catheter body 6603. Such an electrical interconnection member may be in the form of a flexboard.
The hinge 6601 may include a pin 6608 and the deflectable member 6604 may pivot relative to the distal end 6602 about a central axis of the pin 6608. The pin 6608 may, for example, be integral with, or pressed into a corresponding hole of, the deflectable member 6604 such that the pin 6608 is fixed to the deflectable member 6604. The pin 6608 may fit within a hole in the distal end 6602 such that it is free to rotate within the hole as the deflectable member 6604 pivots relative to the distal end 6602. In this regard, the hinge 6601 may include a pair of surfaces (e.g., the outside surface of the pin 6608 and the inside surface of the hole in the distal end 6602) that may slide relative to each other to allow the deflectable member 6604 to deflect. Any other appropriate hinge, including a hinge where the pin 6608 is fixed to the distal end 6602 and free to pivot relative to the deflectable member 6604, may be used in place of the described hinge 6608.
The embodiments of
The catheter 6700 may further include a tube tether 6707. The tube tether 6707 may be a piece of shrink tube (e.g., fluorinated ethylene propylene (FEP) shrink tube) or other bondable tubing with a portion 6708 removed so that the region 6710 of the tube tether 6707 proximate to a hinge line 6709 of the living hinge 6705 is non-tubular and may act as a tether (e.g., in a manner similar to the tether 6009 of
The tube tether 6707 functions to cause the deflectable member 6704 to pivot in a positive direction (e.g., upward as shown in
The flexboard 6802 may have an interconnection section 6806 where the conductors on the flexboard 6802 are spaced to coincide with the spacing of the conductors on the electrical interconnection member 6801. At the interconnection section 6806, the electrically conductive portions (e.g., traces, conductive paths) of the flexboard 6802 may be interconnected to the electrically conductive portions (e.g., wires) of the electrical interconnection member 6801. This electrical interconnection may be achieved by peeling back or removing some of the insulative material of the electrical interconnection member 6801 and contacting the exposed electrically conductive portions to corresponding exposed electrically conductive portions on the flexboard 6802.
As illustrated in
As illustrated in
The electrical interconnection member 6801 may comprise members that extend from a distal end to a proximal end of the catheter body 6803 or the electrical interconnection member 6801 may comprise a plurality of discrete, serially interconnected members that together extend from the distal end to the proximal end of the catheter body 6803. In an embodiment, the flexboard 6802 may include the electrical interconnection member 6801. In such an embodiment, the flexboard 6802 may have a helically wrapped portion extending from the distal end to the proximal end of the catheter body 6803. In such an embodiment, no electrical conductor interconnections (e.g., between the flexboard 6802 and a flat cable) may be required between the flexing region 6807 and the proximal end of the catheter body 6803.
In a variation of the configuration of the electrical interconnections illustrated in
In a first implementation, the single electrical interconnection member may be a flexboard or flex circuit. An exemplary route that may be followed by such a flex circuit would be to run from the proximal end of the catheter (or beyond), turn at an angle to accommodate wrapping in the catheter body wall, turn again at the distal end of the catheter body to run straight through the hinge, turn at a 90 degree angle to be wound as a clock spring within the deflectable member (e.g., to accommodate the reciprocal pivotal motion of a transducer array), and then turn at another 90 degree angle to run over the back of the transducer array and be connected thereto. In a variation, the flex circuit may travel down an interior portion of the catheter body instead of being wrapped in the catheter body wall.
A flex circuit of such a length may be produced from a sheet where the conductors are laid out in a back and forth pattern. The sheet may then be cut such that the conductive strip is configured in an accordion-like pattern. The conductive strip may then be folded at each bend to form a substantially straight single electrical interconnection member (apart from the end features to accommodate the deflectable member and/or connection to the ultrasound console 5706) of a desired length.
Such a single flex circuit configuration may be used with any appropriate embodiment described herein.
In a second implementation, the single electrical interconnection member may be a ribbon cable such as a GORE™ Micro-Miniature Ribbon Cable. Such a cable could be routed from the proximal end of the catheter (or beyond), down an interior portion of the catheter body, and continue through the hinge and then be attached to the back of the array. In such an embodiment, a backplane removed may be removed to increase the flexibility of the ribbon cable in specific areas, such as at the hinge and/or within the deflectable member. To further increase flexibility, the individual conductors of the ribbon cable may be separated in these areas. An example of a ribbon cable where the individual conductors are separated in the region of the hinge is illustrated in
In an alternative arrangement of the second implementation, the individual conductors may be separated proximal to the hinge and may remain separated all the way to a transducer array disposed within the deflectable member (similar to the “flying leads” arrangement as discussed with respect to
Such a single ribbon cable configuration may be used with any appropriate embodiment described herein.
The deflectable member 6900 may include a case 6903. The case 6903 may be a relatively rigid member housing a motor 6904 and a transducer array 6905, both of which are discussed below. The deflectable member 6900 may include a central axis 6906.
An electrical interconnection member 6907 may be partially disposed within the deflectable member 6900. The electrical interconnection member 6907 may include a first portion 6908 disposed outside of the case 6903 (partially illustrated in
The case 6903 may be sealed, and an enclosed volume may be defined by the case 6903 and the end wall 6901. The enclosed volume may be fluid-filled. The transducer array 6905 and an associated backing may be similar to the transducer array 5307 and the associated array backing 5328 discussed with reference to
As shown in
In general, the images generated by the deflectable member 6900 may be of a subject (e.g., internal structure of a patient) within an image volume similar to the image volume 5327 discussed with reference to
The transducer array 6905 may be interconnected at a distal end to an output shaft of the motor 6904. Furthermore, the transducer array 6905 may be supported on a proximal end of the transducer array 6905 by a pivot 6910. The interface between the pivot 6910 and the transducer array 6905 may allow for the transducer array 6905 to reciprocally pivot about its rotational axis while substantially preventing any lateral movement of the transducer array 6905 relative to the case 6903. Accordingly, the transducer array 6905 may be operable to be reciprocally pivoted about its rotational axis.
The motor 6904 may be disposed at the distal end 6902 of the deflectable member 6900. The motor 6904 may be an electrically powered motor operable to selectively rotate the transducer array 6905 in both clockwise and counterclockwise directions. In this regard, the motor 6904 may be operable to reciprocally pivot the transducer array 6905.
The motor 6904 may be fixedly mounted to a motor mount 6911 that is in turn fixedly disposed relative to the case 6903. The motor mount 6911 may be interconnected to the motor 6904 at or near where the output shaft of the motor 6904 is interconnected to the transducer array 6905. Electrical interconnections to the motor 6904 may be achieved through a dedicated set of electrical interconnections (e.g., wires) separate from the electrical interconnection member 6907.
The electrical interconnection member 6907 may be anchored such that a portion of it is fixed relative to the case 6903. The electrical interconnection member 6907 includes a second portion 6909 disposed in the distal end 6902 of the deflectable member 6900 and operable to accommodate the reciprocal motion of the transducer array 6905. The electrical interconnection member 6907 further includes a third portion 6912 disposed along the case 6903 and operable to electrically interconnect the first portion 6908 to the second portion 6909.
The third portion 6912 of the electrical interconnection member 6907 may be anchored such that at least a portion of it is fixed relative to the case 6903. The third portion 6912 of the electrical interconnection member 6907 may be secured to the case 6903 in a region corresponding to the position of the transducer array 6905. In this regard, the third portion 6912 of the electrical interconnection member 6907 may be disposed such that it does not interfere with the reciprocal movement of the transducer array 6905. Any appropriate method of anchoring the third portion 6912 of the electrical interconnection member 6907 to the case 6903 may be used. For example, adhesive may be used.
The second portion 6909 of the electrical interconnection member 6907 is operable to maintain an electrical connection to the transducer array 6905 while the transducer array 6905 is pivoting. This may be achieved by coiling the second portion 6909 of the electrical interconnection member 6907 about the motor 6904 in an area distal to the motor mount 6911. In this regard, the electrical interconnection member 6907 may be coiled about an axis aligned with the axis of rotation of the rotational output of the motor 6904. One end of the second portion 6909 of the electrical interconnection member 6907 may be anchored to the case 6903 and the other end 6913 of the second portion 6909 of the electrical interconnection member 6907 may be electrically interconnected to the transducer array 6905 (through an array backing).
The second portion 6909 of the electrical interconnection member 6907 may have a generally flat cross-section and be disposed such that a top or bottom side of the second portion 6909 faces and wraps about the central axis 6906. The second portion 6909 of the electrical interconnection member 6907 may be coiled in a “clock spring” arrangement where, as illustrated in
One end of the clock spring of the second portion 6909 of the electrical interconnection member 6907 may be electrically interconnected to the third portion 6912, while the other end 6913 may be electrically interconnected to the transducer array 6905 (through the array backing). The clock spring of the second portion 6909 may be comprised of a partial coil or any appropriate number of coils.
Similar to the embodiments of
The clock spring of the second portion 6909, and other clock spring arrangements discussed herein, may provide for increased durability in comparison to a configuration where an electrical interconnection is twisted along its length. The clock spring of the second portion 6909, and other clock spring arrangements discussed herein, may be configured such that when the transducer array 6905 is positioned at the center of its desired range of motion, the clock spring of the second portion 6909 imparts little or no torque on the transducer array 6905. In such a configuration, when the motor 6904 moves the transducer array 6905 from the center position, the clock spring of the second portion 6909 may impart a torque on the transducer array 6905 that urges the transducer array 6905 back toward the center position. Such torque imparted on the transducer array 6905 may be selected to be minimal or it may be selected to assist the motor 6904 in returning the transducer array 6905 to the center position. In another arrangement, the clock spring of the second portion 6909 may be configured to urge the transducer array 6905 to one end of its desired range of motion. The configuration of the clock spring of the second portion 6909 also saves space within the deflectable member 6900 in that the pivoting of the transducer array 6905 may be accommodated by a portion of the electrical interconnection member 6907 (e.g., the second portion 6909) wrapped about a single point along the central axis 6906.
The deflectable member 7000 may include a case 7003 and an end cap 7015. The end cap 7015 may be sized to fit within and seal the distal end 7002 of the case 7003. The case 7003 may be a relatively rigid member housing a motor 7004 and a transducer array 7005, both of which are discussed below.
An electrical interconnection member 7007 may be partially disposed within the deflectable member 7000. The electrical interconnection member 7007 may include a first portion 7019 disposed outside of the case 7003 that may be operable to electrically interconnect members within the deflectable member 7000 to electrical conductors in a catheter to which the deflectable member 7000 is attached (e.g., in a manner as discussed with reference to flexboard 6802 of
In general, the deflectable member 7000 may be used in the process of generating images similar to as described above with reference to the deflectable member 6900. In this regard, the transducer array 7005 may be disposed on a mechanism operable to reciprocally pivot the transducer array 7005.
The transducer array 7005 may be fixed to and supported by a pair of array end caps 7008 disposed at opposing ends of the transducer array 7005. In turn, a pair of shafts 7009 may be fixedly inserted into corresponding holes in the array end caps 7008. One of the shafts 7009 may be disposed within a bearing 7010 that may be mounted to the end cap 7001. The bearing may allow the shaft 7009 disposed therein (and therefore the transducer array 7005 that is interconnected to the shaft 7009) to pivot relative to the end cap 7001. The other shaft 7009, disposed at a distal end of the transducer array 7005, may be fixed to a coupling 7011 that is in turn fixed to an output shaft 7012 of the motor 7004. Thus the transducer array 7005 may be fixed relative to the output shaft 7012 of the motor 7004 such that the motor 7004 may reciprocally pivot the transducer array 7005 about an array rotational axis defined by the output shaft 7012 and shafts 7009.
The motor 7004 may be disposed at the distal end 7002 of the deflectable member 7000. The motor 7004 may be an electrically powered motor operable to selectively pivot the transducer array 7005 in both clockwise and counterclockwise directions.
The motor 7004 may be disposed within a motor mount 7013 that is in turn fixedly disposed relative to the end cap 7001 via a pair of rods 7016. The pair of rods 7016 fix the motor mount 7013 to the end cap 7001 such that the motor mount 7013 is at a fixed distance from the end cap 7001 such that the transducer array 7005, array end caps 7008, and shafts 7009 may be disposed between the motor mount 7013 and the end cap 7001. Electrical interconnections to the motor 7004 may be achieved through a dedicated set of electrical interconnections 7018 (e.g., wires) separate from the electrical interconnection member 7007. It will be appreciated that such construction allows for the transducer array 7005, motor mount 7013, and motor 7004 to be mounted to the end cap 7001 in a sub-assembly. Subsequently, the case 7003 may be installed over such a sub-assembly.
An o-ring 7017 may be disposed about the output shaft 7012 of the motor 7004. The o-ring 7017 may be sandwiched between a proximal end of the motor mount 7013 and a plate 7022. Moreover, the proximal end of the motor 7004 (i.e., the end of the motor 7004 with the output shaft 7012) may also be disposed in the region between the proximal end of the motor mount 7013 and the plate 7022. Grease may be inserted in the region between the proximal end of the motor mount 7013 and the plate 7022 and on the o-ring 7017. The grease may restrict liquids from entering the region between the proximal end of the motor mount 7013 and the plate 7022 and therefore help to prevent liquids from entering the motor 7004 through the proximal end of the motor 7004. The motor mount 7013 and the plate 7022 may be sized to assist in restricting liquid from entering the region between the proximal end of the motor mount 7013 and the plate 7022. The plate 7022 may be fixed relative to the motor mount 7013 by the rods 7016 and a pin 7025.
The case 7003 may be sealed, and an enclosed volume may be defined by the case 7003, the end cap 7015, and the end cap 7001. The enclosed volume may include a proximal enclosed volume 7023 in the region between the plate 7022 and the end cap 7001 and a distal enclosed volume in the region between the proximal end of the motor mount 7013 and the end cap 7015.
The proximal enclosed volume 7023 may be fluid-filled. The transducer array 7005 and an associated backing may be similar to the transducer array 6905 and the associated array backing discussed with reference to
The distal enclosed volume 7024 may be fluid-filled. The fluid in the distal enclosed volume 7024 may be selected to provide a heat dissipation medium to cool the motor 7004. A sealant, such as an ultraviolet (UV) cured epoxy, may be placed around the portion of the motor 7004 where the electrical connections 7018 enter into the motor 7004 to restrict the ability of liquid to enter into the motor 7004. In this regard, through the use of the UV cured epoxy and the above-described grease, the motor 7004 may be of a type not specifically designed to be operable in a liquid-filled environment. Alternatively, a sealed motor designed to be operable in a liquid-filled environment may be used.
The electrical interconnection member 7007 may be a flexboard or other appropriate flexible multiple conductor member. The first portion 7019 may also serve as a tether. The electrical interconnection member 7007 may pass between the end cap 7001 and the case 7003 as it passes from the area proximate to the hinge 7014 to the interior of the deflectable member 7000. In this regard, the electrical interconnection member 7007 may be securely held between the end cap 7001 and the case 7003.
A second portion of the electrical interconnection member 7007 may be disposed within the deflectable member 7000 and may run from the end cap 7001 to the back side of the transducer array 7005. In particular, the second portion 7020 may run along the length of the transducer array 7005 in the space between the back side of the transducer array 7005 and the case 7003. At the distal end of the transducer array 7005, the second portion 7020 may wrap around a pin 7021 and then run along, and be in contact with, the backside of the transducer array 7005 to electrically interconnect to the transducer array 7005 (through a backing of the transducer array 7005).
The pin 7021 may be secured to the second portion 7020 and the second portion may be secured to the back side of the transducer array 7005. Thusly, the portion of the second portion 7020 in contact with the pin 7021 and the portion of the second portion 7020 in contact with the back side of the transducer array 7005 may be fixedly interconnected to the transducer array 7005. With the second portion 7020 secured to the pin 7021, the reciprocal pivotal motion of the transducer array 7005 may cause the second portion 7020 to flex in the region between where it is secured to the pin 7021 and where the second portion is secured between the end cap 7001 and the case 7003. Accordingly, the second portion 7020 of the electrical interconnection member 7007 is operable to maintain an electrical connection to the transducer array 7005 while the transducer array 7005 is pivoting.
The electrical interconnection member 7110 may be partially disposed within the deflectable member 7103. The electrical interconnection member 7110 may be fixed relative to deflectable member 7103 where the electrical interconnection member 7110 enters the deflectable member 7103. In this regard, stresses on the electrical interconnection member 7110 (e.g., due to its tethering function) may not be translated into the interior of the deflectable member 7103.
The case 7109 may be sealed, and an enclosed volume may be defined by the case 7109, an end wall 7111, and an end cap 7112. The enclosed volume may be fluid-filled. The enclosed volume may be filled by inserting fluid through a fluid port 7113 while allowing air within the enclosed volume to escape through an air vent 7114. Both the fluid port 7113 and the air vent 7114 may be sealed after the enclosed volume if filled with fluid. The case 7109 may include an acoustic window.
The transducer array 7105 and an associated backing may be similar to the transducer array 6905 and backing discussed with reference to
The transducer array 7105 may be fixed to and supported by a proximal array end cap 7115 and a coaxial distal array end cap 7116 disposed at opposing ends of the transducer array 7105. A proximal shaft 7117 may be fixedly inserted into the proximal array end cap 7115. A distal shaft 7118 may be fixedly inserted into the distal array end cap 7116. The proximal shaft 7117 may be pivotably disposed within the end wall 7111 (e.g., within a bearing). The distal shaft 7118 may be pivotably disposed within the end cap 7112 (e.g., within a bearing). Thus, the transducer array 7105 may be operable to pivot about an axis defined by the distal shaft 7118 and the proximal shaft 7117.
The motor 7104 is disposed between a back side of the transducer array 7105 and a sled 7119 that is adjacent to a portion of the case 7109. In this regard, the motor 7104 and transducer array 7105 may be co-located at a common point along a longitudinal axis of the deflectable member 7103. The sled 7119 may support a pair of motor mounts 7123 that in turn, support the motor 7104. In this regard, the position of the motor 7104 may be fixed relative to the case 7109 and therefore also relative to the transducer array 7105. A transmission 7120 may operatively interconnect an output shaft (not shown) of the motor 7104 to the transducer array 7105 such that the motor 7004 may cause the transducer array 7105 to reciprocally pivot about the axis defined by the shafts 7117, 7118. The transmission 7120 may include any appropriate mechanism, such as two or more gears, a belt, a cam, or rigid links, that is able to communicate the output of the motor 7104 to a reciprocal pivotal motion of the transducer array 7105. In this regard, the motor 7104 may be operable to reciprocally pivot the transducer array 7105. The motor 7104 may be operable to be reciprocally driven, and the transmission 7120 may transmit such reciprocal motion of the output of the motor 7104 to reciprocally pivot the transducer array 7105. In another arrangement, the motor 7104 may be operable to be continuously driven in a selected direction, and the transmission 7120 may convert such continuous rotation of the output of the motor 7104 to a motion for reciprocally pivoting the transducer array 7105. Electrical interconnections to the motor 7104 may be achieved through a dedicated set of electrical interconnections 7112 (e.g., wires) separate from the electrical interconnection member 7110.
As noted, the electrical interconnection member 7110 may be fixed relative to deflectable member 7103 where the electrical interconnection member 7110 enters the deflectable member 7103. Within the deflectable member 7103, the electrical interconnection member 7110 may include a clock spring portion 7121 similar to the clock spring arrangement of the second portion 6909 of the embodiment of
Springs 7209 may be disposed between the ends of the cable 7206 and the distal array end cap 7207. Such springs 7209 may compensate for the non-linear variations in the distances between the anchor points of the cable 7206 to the distal array end cap 7207 as the transducer array 7205 pivots relative to the motor 7204. The springs may include a resilient polymer portion disposed between a top plate (to which the cable 7206 may be secured) and the distal array end cap 7207.
The deflectable member 7303 may generally include a distal end 7308 and a proximal end 7309. The deflectable member 7303 may include a case 7312. The case 7312 may be a relatively rigid (as compared to the catheter body 7301) member housing a motor 7304 and a transducer array 7305, both of which are discussed below. The deflectable member 7303 may include a longitudinal axis 7313.
Within the deflectable member 7303, the electrical interconnection member 7310 may run from the proximal end 7309 along the case 7312 between an array backing 7316 and the inner wall of the case 7312, to a clock spring portion 7317 of the electrical interconnection member 7310. From the clock spring portion 7317, the electrical interconnection member 7310 may interconnect to the array backing 7316. This configuration is similar to the configuration of the electrical interconnection member 5311″ of
The proximal end 7309 of the deflectable member 7303 may include an end member 7318 sealably disposed therein. The end member 7318 may be sealed along its outer perimeter using a sealing material 7319. The sealing material 7319 may be disposed as illustrated between the outer perimeter of the end member 7318 and an inner surface of the case 7312. The sealing material 7319 may be similar to the sealing material 5316 of
The deflectable member 7303 may be filled using any appropriate method. The deflectable member 7303 may include a pair of sealable ports 7321, 7322 disposed on opposite ends of the deflectable member 7303. The sealable ports 7321, 7322 may allow for filling of the deflectable member 7303 in a manner similar to as described with reference to the catheter tip 5301 of
The deflectable member 7303 may include a bubble-trap 7324, shown in cross section in
The deflectable member 7303 may be operable to reciprocally pivot the transducer array 7305 at a rate sufficient enough to generate 3D or 4D images of an image volume 7325. In this regard, the ultrasound imaging apparatus may be operable to display live video of the image volume. Generally, the transducer array 7305 is operable to transmit ultrasonic energy through an acoustic window 7326 of the case 7312.
The transducer array 7305 may be interconnected to an output shaft 7327 of the motor 7304 at a proximal end of the transducer array 7305. Furthermore, the transducer array 7305 may be supported on a distal end of the transducer array 7305 by a shaft 7328 that is supported at the distal end of the case 7312. The motor 7304 may be operable to reciprocally pivot the output shaft 7327 of the motor 7304 and therefore reciprocally pivot the transducer array 7305 interconnected to the output shaft 7327. The outer portion of the motor 7304 may be fixedly mounted to the inner surface of the case 7312 by one or more motor mounts 7329. Electrical interconnections (not shown) to the motor 7304 may be achieved through a dedicated set of electrical interconnections (e.g., wires) separate from the electrical interconnection member 7310. Alternatively, electrical interconnections to the motor 7304 may be made using a portion of the conductors of the electrical interconnection member 7310.
The positions of the motor 7304, the clock spring portion 7317, and the transducer array 7305 may be rearranged in any appropriate manner. For example,
The catheter 7300′ of
The transducer array 7305 may be interconnected to an output shaft 7327′ of the motor 7304′ at a proximal end of the transducer array 7305. The output shaft 7327′ may extend through the clock spring portion 7317′. Furthermore, the transducer array 7305 may be supported on a distal end of the transducer array 7305 by a shaft 7328′ that is supported at the distal end of the case 7312′. The motor 7304′ may be operable to reciprocally pivot the output shaft 7327′ of the motor 7304 and therefore reciprocally pivot the transducer array 7305 interconnected to the output shaft 7327′. The acoustic window 7326′ may encircle the entire circumference of the case 7312′ or a portion thereof in the area of the transducer array 7305 to allow for imaging in directions as discussed below.
The motor 7304′ may be operable to reciprocally pivot the transducer array 7305 from the position illustrated in
The motor 7304′ may also be operable to first pivot the transducer array 7305 to a selected orientation and then reciprocally pivot the transducer array 7305 about the selected orientation a chosen distance. For example, the motor 7304′ may be operable to pivot the transducer array 7305 180 degrees from the position shown in
The motor 7304′ may be operable to reciprocally pivot the transducer array 7305 through 360 degrees or more. In this regard, the deflectable member 7330 may be operable to reciprocally pivot the transducer array 7305 through an angle large enough and at a rate sufficient enough to generate real-time or near real-time three-dimensional images of an image volume that completely encircles the deflectable member 7330.
The clock spring portion 7317′ may be configured to accommodate 360 degrees or more of rotation of the transducer array 7305. Such accommodation may be achieved by a single clock spring portion 7317′ or by multiple clock spring portions arranged in series with each portion accommodating a portion of the total pivoting of the transducer array 7305. In an arrangement, the clock spring portion 7317′, the motor 7304′, and the acoustic window 7326′ may be configured to accommodate a range of angular motion less than 360 degrees (e.g., 270 degrees, 180 degrees).
The motors driving motion (e.g., pivotal reciprocal) of transducer arrays discussed herein may be integrated into any appropriate embodiment discussed herein. The motors discussed herein (e.g., motor 6904) may be brushless DC motors. Wherein the motor used is a brushless DC motor, there are three wires driving three phases of motor current. The motor may be driven using pulse width modulation. In such a case the driver sends out pulses at, for example, a 40 KHz rate to keep the current at the desired level. Because of the sharp edges on the pulses this kind of driver can cause interference with the ultrasound system. To avoid this, a shield may be disposed around the motor wires to keep the interfering signal from passing to the conductors electrically connected to the transducer array. In another implementation, the pulse width modulation may be filtered to reduce the signal in the frequency band used by the transducer array (e.g., in the ultrasound frequency band). In a particular implementation, both the shielding and the filtering may be used. The motor may alternatively be driven by an analog driver that produces a continuous current (without pulses) to drive the motor.
Acoustic, capacitive, electromagnetic and optical sensor techniques may be utilized as means for detecting the angular position of any appropriate pivotable transducer array discussed herein. Based upon the data from the sensors, operation of the pivotable transducer array may be adaptively adjusted in order to compensate for variations in angular velocity of the pivotable transducer array. For example, adaptive compensation may be performed by adjusting the pulse repetition rate of transmitted ultrasonic energy, by adjusting the scan conversion algorithm, or by varying control of the motor to vary control of the rotation of the pivotable transducer array.
Any known sensor may be utilized in the embodiments discussed herein, including encoding by optical means including rotational encoders, distance by interferometry and/or brightness proximity, capacitive encoders, magnetic encoders, ultrasonic encoders, flexure of a flexible encoder membrane, and utilization of accelerometers.
One embodiment may use the sensor positioning data in comparison with a desired position utilizing a software program in a feedback system. If the actual position is behind the desired position (e.g., the angular position of pivotable transducer array is behind the desired angular position of the pivotable transducer array), a servo system may compensate by increasing the motor or drive operation. Conversely, if the actual position is ahead, the servo system may compensate by slowing the motor or drive.
Embodiments discussed herein of deflectable members may have an enclosed portion which may or may not contain a fluid. This fluid provides an acoustic coupling medium between the ultrasound transducer array and the acoustic window or tip. An additional benefit may be to provide cooling for the motor. Generally, the maximum desired temperature of a catheter operating in the body is about 41° C. Normal blood temperature is about 38° C. Under such circumstances, there may be a need to balance the power dissipation in the tip and the heat flow out of the tip such that the tip does not exceed a rise of about 3° C. above 38° C. Actual temperature monitoring near the distal end of the catheter body and in the deflectable member is desirable, with feedback to a controller with an automatic warning or shut down based upon some upper pre-determined temperature limit. A thermistor may be mounted within the tip to monitor the internal temperature so that the system may shut down operations before the temperature exceeds the pre-determined temperature limit. A thermocouple would be a suitable alternative to the use of a thermistor.
Active cooling methods such as thermoelectric cooling or passive conduction along metallic components may also be used in the embodiments discussed herein. Other types of thermal management systems, such as those disclosed in U.S. Patent Publication No. 2007/0167826, may be used in the embodiments discussed herein.
Fluid selected for use in the enclosed portion may provide: desired acoustic properties, desired thermal properties, appropriate low viscosity to not impede oscillatory motion of the array or other components, non-corrosiveness to components, and compatibility with the circulatory system and the rest of the human body in case of leakage. Fluids may be selected to avoid or minimize evaporation or development of bubbles over time. Embodiments discussed herein may have the fluid injected at the time of manufacture or at the point of use. In either case, the fluids may be sterile and miscible with water. Sterile saline is an example of a fluid that may be used in the embodiments discussed herein.
Embodiments discussed herein may include a deflectable member having a cylindrical shape or other shape designed to minimize vascular or bodily injury when moved (e.g., rotated, translated) or operated within a patient. Moreover, the outer surface of the deflectable members may be smooth. Such a smooth, atraumatic exterior profile may help in reducing thrombus formation and/or tissue damage. Such atraumatic shapes may be beneficial in reducing turbulence which may cause injury to blood cells.
Embodiments discussed herein generally described as including transducer arrays, ultrasound transducer arrays, or the like. However, it is also contemplated that the catheters discussed herein may include other appropriate devices in place of or in addition to such devices. For example, embodiments discussed herein may include ablation or other therapeutic devices in place of or in addition to the transducer arrays, ultrasound transducer arrays, or the like.
One difficulty associated with the use of conventional ICE catheters is the need to steer the catheter to multiple points within the heart in order to capture the various imaging planes needed during the procedure.
With the deflectable member positioned as illustrated in
Clinical procedures that may be performed with embodiments disclosed herein include without limitation septal puncture and septal occluder deployment. A method for right atrial imaging utilizing embodiments may include advancing the catheter body to the right atrium, steering the distal end of the catheter body to a desired position, operating the motor to effectuate movement of the ultrasound transducer, and while maintaining the fixed catheter body position, deflect the deflectable member comprising the ultrasound transducer about the hinge to capture at least one image over at least one viewing plane.
Clinical procedures that may be performed from the left atrium include without limitation, left atrial appendage occluder placement, mitral valve replacement, aortic valve replacement, and cardiac ablation for atrial fibrillation. A method for left atrium imaging utilizing embodiments described herein may include advancing the catheter body to the right atrium, steering the distal end of the catheter body to a desired position, and while maintaining the fixed catheter body position, deflect the deflectable member comprising the ultrasound transducer about a hinge to achieve a desired position, operating the motor to effectuate movement of the ultrasound transducer to capture at least one image over at least one viewing plane of the intra-atrial septum, identify the anatomical region for septal puncture, advance a septal puncture tool through a lumen of the catheter, advance a guidewire, advance the catheter body to the left atrium, steer the catheter body to the desired position, and while maintaining the fixed catheter body position, deflect the deflectable member comprising the ultrasound transducer about the hinge to a desired position, and operate the motor to effectuate movement of the ultrasound transducer to capture at least one image over at least one viewing plane.
Additional modifications and extensions to the embodiments described above will be apparent to those skilled in the art. Such modifications and extensions are intended to be within the scope of the present invention as defined by the claims that follow.