The invention generally relates to methods and systems for monitoring the location of a device within intraluminal and extraluminal regions of a patient.
The ability to monitor the location and orientation of surgical instrumentation within intraluminal and extraluminal regions of a patient is critical. Fluoroscopy and radiopaque materials have traditionally been used to create visible regions of the digestive tract. Fluoroscopy is a technique in which an x-ray beam is transmitted through a patient to generate images of the gastrointestinal (GI) lumen that appear on a television monitor. It can also be used to observe the action of instruments during diagnostic procedures. However, x-rays consist of electromagnetic radiation which can be dangerous to the bile duct and pancreatic duct.
Conventional endoscopy offers visualization of the intraluminal regions through which the endoscope is inserted due to a video camera attached at the distal end of the endoscope. However, the video camera provides a field of view limited to only the intraluminal region. The use of surgical instrumentation outside of the lumen into extraluminal regions cannot be visualized with the endoscopic video camera.
Medical ultrasound has been another option used to monitor instrumentation. Medical ultrasound utilizes high frequency sound waves to create an image of living tissue. As ultrasound waves are emitted, the waves reflect when encountering a surface change. The reflected waves are used to create an image. However, conventional medical ultrasound has the drawback of ultrasound attenuation occurring in which a significant loss of energy occurs as the ultrasound waves pass through biological tissue. Consequently, poor images are created.
In view of the drawbacks of current technology, there is an unmet need to effectively monitor the real-time location, orientation, and depth of penetration of medical devices guided within intraluminal and extraluminal regions of a patient. Such monitoring is necessary to ensure medical devices are guided to their target sites and not inadvertently damaging adjacent tissue. Furthermore, the ability to perform such real-time monitoring of the devices will shorten surgical procedure times.
Accordingly, an endoscopic ultrasound (EUS)-guided device system is provided.
In one aspect, a system is disclosed for monitoring the location of a device within intraluminal and extraluminal regions. This is accomplished by an endoscopic ultrasound (EUS)-guided device system. The EUS-guided device system includes a linear echoendoscope and a device having an echogenic surface. The device contains a lumen adapted to receive a wire guide having an echogenic surface. Ultrasounds are emitted from transducers located at the distal end of the linear echoendoscope. The reflections of ultrasound waves from the echogenic surfaces of the wire guide and device enable a surgeon to precisely monitor the location of the wire guide and device within the lumen and extraluminal regions of a patient.
In a second aspect, a EUS-guided device system is disclosed for monitoring devices as they create access to extraluminal regions within a patient. The system includes a linear echoendoscope and a needle having a lumen and an echogenic surface. A wire guide having an echogenic surface coaxially fits within the lumen of the needle. Incorporation of echogenicity on the needle device and wire guide device enables a surgeon to precisely monitor the location of the devices as they are advanced to selected extraluminal regions in a patient and removed therefrom.
In a third aspect, a method for guiding a device in an intraluminal or extraluminal region is disclosed. The method includes positioning a linear echoendoscope within the lumen of a patient. The device is loaded coaxially through an accessory channel of the linear echoendoscope. Linear array transducers are activated. As the distal end of the device passes through the distal end of the accessory channel, the echogenic surface of the device encounters incident ultrasound waves emitted from a series of linear array transducers. A real-time ultrasonic image of the device is generated as the reflected ultrasound waves are detected by the transducers. The surgeon receives the real-time ultrasonic image of the device and then can determine the precise location of the device within the intraluminal or extraluminal region of a patient. After determining the location of the device, the surgeon can make any necessary adjustments to the location of the device to ensure the device is guided to the target site.
Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which:
The term echogenic refers to the extent that a surface reflects incident ultrasound wave energy directly back to a transducer or series of transducers. Enhanced echogenicity of a surface can be created by any technique that creates a surface indentation such that the dimensions of the surface indentation are substantially less than the incident ultrasonic sound waves. Intensity of the reflected and scattered waves is amplified by increasing the change in acoustic impedance between the surrounding medium (e.g., biological tissue) and the echogenic surface.
One embodiment of the present invention incorporates echogenicity into medical devices commonly used in endoscopic retrograde cholangiopancreatography (ERCP) to identify and retrieve gallstones or other foreign matter from the biliary and pancreatory ducts. By way of a non-limiting example,
EUS-guided device system 10 comprises a linear echoendoscope 11 and a basket assembly 15 (shown in
An elevational view of an echogenic wire guide 50 is shown in
A side view of the basket assembly 15 is shown in
Multiple echogenic surfaces 26 along each of the arms, shown in
Providing echogenicity at the convergence of arms 18 at their distal end 24 and proximal end 22, as shown in
Referring back to
As the distal end 47 of wire guide 50 emerges from the distal end 88 of accessory channel 29 of linear echoendoscope 11, the surgeon is provided with visualization of echogenic surface 49. Ultrasound waves emitted from the linear array of transducers 14 are reflected from echogenic surface 49, thereby causing a sonographic image to appear on a EUS display panel (not shown). Because the linear array of transducers 14 are small enough to be located on the distal end 39 of linear echoendoscope 13, as shown in
A real-time image is constructed from a series of small pixels on EUS display screen. Each dot represents a single reflected ultrasound pulse. The brightness of each pixel varies with the amount of reflected ultrasound energy. The location of the pixel represents the position of the reflecting interface. Consequently, on a EUS display screen, reflecting areas of high intensity appear white (hyperechoic) and areas of low reflection appear dark (hypoechoic). Such enhanced ultrasonic visualization will allow the surgeon to precisely navigate wire guide 50 through papilla opening 5 and into biliary duct 3 towards gallstone 31. Because gallstone 31 is hyperechoic, the surgeon will be able to continuously monitor the location of echogenic wire guide 50 in relation to gallstone 31. The entire path of wire guide 50 towards gallstone 31 may be visualized.
After the surgeon has positioned wire guide 50 into biliary tract 3 and in close proximity to gallstone 31, basket assembly 15 can be loaded into accessory channel 29 coaxially over wire guide 50, which serves as a stable guide to facilitate deployment of basket assembly 15 into biliary duct 3.
The ability to observe the positions of both gallstone 31 and basket assembly 15 significantly reduces the amount of time a surgeon must expend within biliary duct 3. Such a reduction in procedure time also mitigates patient trauma and potential injury to bile duct 3 due to inadvertent puncture of adjacent tissue.
Although the above procedure has been described with the echogenic basket assembly 15 mounted onto an echogenic wire guide 50, the embodiment also contemplates navigation of the basket assembly 15 without any wire guide. Furthermore, the embodiment also contemplates various other medical devices having echogenic surfaces which may be used with or without a wire guide.
In accordance with another embodiment of this invention, echogenicity can also be incorporated on a variety of GI devices to perform procedures in the extraluminal regions. By way of a non-limiting example,
EUS-guided device system 51 comprises linear echoendoscope 11, needle 56 (as shown in
Needle 56, shown in
Although needle 56 is illustrated to have only one echogenic surface 58, multiple echogenic surfaces can also be used. Multiple echogenic surfaces that are spaced apart at predetermined distances can permit greater determination of the location and orientation of a EUS-guided needle. As an example,
Echogenic surfaces 60, 61, and 70 also provide the ability to monitor the orientation of needle 59. Three distinct echogenic regions on needle 59 will generate three distinct white pixels on the EUS display panel (not shown) when echogenic surfaces 60, 61, and 70 are within the field of view of ultrasonic scanning plane 30. The relative vertical and horizontal orientation of the three pixels on the EUS display panel corresponds to the orientation of needle 59 within extraluminal region 2. Such real-time information can be used by the surgeon to determine whether the distal end 62 of needle 59 is in proper orientation to make the desired puncture upon reaching stomach wall 66. If needle 59 is not in its proper orientation, then the surgeon will know to remaneuver needle 59 accordingly until the desired orientation appears on the EUS display panel.
Additionally, multiple distinct regions of echogenicity on needle 59 may also convey depth of penetration of needle 59 into pseudocyst 55.
Referring back to
At this stage, the surgeon turns on linear array transducers 14, located at the distal tip of linear echoendoscope 11. Transducers 14 are sequentially activated via time delay circuits in such a manner that a wedge-shaped ultrasonic scanning plane 30 encompasses needle 56. Because ultrasonic scanning plane 30 is parallel to longitudinal shaft 34, the entire path of needle 56 to stomach wall 66 can be followed as echogenic surface 58, shown in
After needle 56 has created access into pseudocyst 55, wire guide 50 is loaded through the proximal end 13 of linear echoendoscope 11 coaxially into the lumen 65 of needle 56. As the distal end 47 of wire guide 50 emerges from accessory channel 29, visualization of the path of wire guide 50 through punctured pseudocyst 55 may be monitored as ultrasound waves emitted from linear array transducers 14 are reflected back from echogenic surface 49 towards transducers 14 thereby causing a sonographic image to appear on a EUS display panel (not shown). The entire path of wire guide 50 towards stomach wall 66 may be followed as echogenic surface 49 portion emerges out of the distal end 88 of accessory channel 29 towards the puncture site of pseudocyst 55.
With wire guide 50 maintaining access at the puncture site of pseudocyst 55, needle 56 can be withdrawn. Accordingly, needle 56 is withdrawn from pseudocyst 55 and back into accessory channel 29, and upwards through longitudinal shaft 34 of linear echoendoscope 11. The surgeon may accurately monitor withdrawal of needle 56 as ultrasound imaging provides real-time information concerning the location of distal echogenic surface 58 of needle 56.
Echogenic wire guide 50 may now act as a stable guide. Several stents 85, each as shown in
Deploying stent 85 into the hole of pseudocyst 55 may include the following steps. The surgeon first advances distal end 80 of stent 85 into the accessory channel 29 of linear echoendoscope 11. As the distal end 80 emerges from the distal end 88 of accessory channel 29, a ultrasonic scanning plane 30 is generated by linear array transducers 14. Ultrasound waves emitted from linear array transducers 14 are reflected back from echogenic surfaces 81, 82, 83 to transducers 14. Linear array transducers 14 detect the reflected waves and translate the waves back into electrical signals for processing into an image on the EUS diplay monitor (not shown). Because ultrasonic scanning plane 30 is parallel to longitudinal shaft 34, the entire path of stent 85 to pseudocyst 55 can be followed via ultrasonic visualization of echogenic surfaces 81, 82, 83.
The ability for a surgeon to continuously monitor real-time location and orientation of the path of stent 85 may allow the surgeon to make adjustments to the path of stent 85, if necessary. Such adjustments may help avoid damage to adjacent tissue and help deploy stent 85 with optimal orientation into pseudocyst 55. Multiple echogenic surfaces 81, 82, 83 may also serve to enhance ultrasonic visualization during deployment of stents 85 by assuring stents 85 remain in the field of view of ultrasonic scanning plane 30 if incident ultrasound waves inadvertently miss reflecting off the distal-most echogenic surface 81 of stent 85. Moreover, echogenic surfaces 81, 82, 83 provide the surgeon information regarding depth of penetration of stent 85 into pseudocyst 55. Such precise echogenic guiding may allow the surgeon to deploy multiple stents 85 to further dilate hole of pseudocyst 55 for quicker drainage, which in turn may lead to faster recovery times.
In accordance with another embodiment of the present invention, echogenic technology allows traditional intraluminal devices to also be used to gain access to extraluminal regions. As a non-limiting example, needle knives of the type commonly used to access the bile duct 3 may be modified to incorporate echogenicity to the distal portion thereof to expand its applications to access extraluminal regions.
Referring back to the method for drainage of pseudocyst 55 depicted in
As an alternative to having one echogenic distal end 87 as shown in
After dilation of the hole is completed by electrocautery wire 90, one or more stents 85, as shown in
In accordance with another embodiment of the present invention, incorporation of echogenicity to GI accessories can significantly enhance EUS-guided fine-needle aspiration (FNA) biopsies of mucosal and submucosal lesions, peri-intestinal structures including lymph nodes, as well as masses arising in the pancreas, liver, adrenal gland, and bile duct.
EUS-guided device system 95 comprises linear echoendoscope 11, needle 100, and cytology brush 110. Biopsy needle 100 is illustrated in
As an alternative to having one echogenic surface 102 about distal end 130 of catheter 101, it should be understood that multiple echogenic surfaces about distal end 131 may also be added to determine vertical and horizontal orientation of needle knife 89 and the depth of penetration of needle knife 89. Furthermore, multiple echogenic surfaces positioned proximal to echogenic surface 102 provide additional visible regions when incident ultrasound waves are not capable of reflecting off the distal-most echogenic surface 102 of catheter 101. Such additional visible regions may assure that catheter 101 remains in the field of view of ultrasonic scanning plane 30.
After biopsy needle 100 has been precisely guided to mass 96, the surgeon may puncture mass 96 with swift back and forth movements of the biopsy needle 100 until distal end 130 has entered mass 96. Upon successful insertion of distal end 130 into mass 96, stylet 106 may be removed. The path of stylet 106 during its removal can be monitored by ultrasound waves reflecting off echogenic surface 105. As an alternative to one echogenic distal region, multiple echogenic surfaces about distal end 129 may be employed to enable the surgeon to determine the vertical and horizontal orientation of stylet 106 as it is guided towards the distal end 88 of accessory channel 29.
Aspiration of the contents from mass 96 includes applying negative pressure with a vacuum locking syringe (not shown) placed over or otherwise connected to the proximal end of catheter 101. Multiple to and fro movements of catheter 101 may be required to gain an adequate sample. At this point in the procedure, the surgeon monitors the relative location of echogenic surface 102 in relation to mass 96. Failure to monitor the location of catheter 101 may result in inadvertent withdrawal of catheter 101 outside of mass 96 during aspiration and into the intestinal lumen where mass 96 can be contaminated by luminal contents and the epithelium. The reflectance of ultrasound waves from echogenic surface 102 back towards linear array transducers 14 will enable the surgeon to monitor the real-time location of biopsy needle 100 during aspiration and avoid unintended movement of biopsy needle 100 into the intestinal lumen.
If the surgeon is not able to aspirate mass 96, then cytology brush 110 can be used to partially liquidate mass 96 with bristles 111. Wire guide 50 may be loaded through accessory channel 29 and thereafter navigated towards catheter 101 and into lumen 103 of catheter 101. As wire guide 50 emerges from the distal end 88 of accessory channel 29 into the GI lumen 1 (see
With wire guide 50 loaded into lumen 103, the catheter 101 component of the biopsy needle 100 can be removed. The location of catheter 101 during its removal can be precisely controlled by monitoring the location of echogenic surface 102. As an alternative to the one echogenic surface 102 shown in
After biopsy needle 100 has been removed, cytology brush 110 can now be inserted through linear echoendoscope 11 and into accessory channel 29. Wire guide 50 may act as a stable guide when disposed within the lumen 113 of cytology brush 10. As cytology brush 110 emerges from the distal end 88 of accessory channel 29 and begins its path towards mass 96, echogenic surface 112 will provide a visual marker the surgeon may use to achieve controlled ultrasound- guided maneuvering. Upon reaching mass 96, bristles 111 can be used to gradually blunder mass 96 until it partially liquidates. When mass 96 has been sufficiently blundered, cytology brush 110 is withdrawn from mass 96 and catheter 101 is reintroduced for aspiration. Visualization of echogenic surface 102 of catheter 101 and echogenic surface 112 of cytology brush may provide precise maneuvering and orientation thereby assuring a rapid exchange of the two devices. Such visualization may also provide a safe exchange of the two devices due to reduction of risk of inadvertent damage to surrounding tissue.
One of ordinary skill would realize that the above described EUS-guided device system 95 and method of uses thereof can also be used to inject seeds and other therapeutic agents into targeted extraluminal regions.
The above embodiments describing the EUS-guided device systems contemplate using the echogenic devices with or without a wire guide or echogenic wire guide.
One of ordinary skill would recognize that there are multiple obvious variations of echogenic surfaces on devices that can be utilized in accordance with all of the disclosed embodiments of the present invention. As an alternative to having only the top surface of a device echogenic, one of ordinary skill would realize that all of the described echogenic devices can have a circumferential echogenic band about the distal end to facilitate enhanced ultrasonic visualization.
Additionally, to reduce trauma, devices containing lumens can utilize their inner surface walls as the echogenic surface thereby allowing a smooth outer wall that eliminates tissue trauma associated with movement of devices with echogenic outer surface indentations.
The above Figures and disclosure are intended to be illustrative and not exhaustive. This description will suggest many variations and alternatives to one of ordinary skill in the art. All such variations and alternatives are intended to be encompassed within the scope of the attached claims. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the attached claims. For example, the invention has been described in the context of accessing the biliary and pancreatic ducts, stomach wall, and pancreas. Application of the principles of the invention to access other body cavities, such as the thoracic cavity, by way of a non-limiting example, are within the ordinary skill in the art and are intended to be encompassed within the scope of the attached claims. Moreover, in view of the present disclosure, a wide variety of EUS guided device systems and methods of their uses will become apparent to one of ordinary skill in the art.
This application claims the benefit of priority from U.S. provisional application No. 60/657,540 filed Feb. 28, 2005, which is incorporated herein by reference.
Number | Date | Country | |
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60657540 | Feb 2005 | US |