Aspects of this disclosure generally relate to cytology brush systems and related methods. In particular, aspects of this disclosure relate to cytology brushes configured to be guided by guide wires and methods of using such cytology brushes.
Analyzing cell samples can be a helpful tool in the diagnosis and treatment of disease. Undiagnosed pain, unusual symptoms, unusual or abnormal samples, or other factors can require further investigation, and such investigation often necessitates using advanced medical devices. Medical devices, such as cytology brushes or other suitable devices, may be employed for a variety of diagnostic and surgical procedures. Many of these procedures involve delivering the cytology brush to an internal stricture (e.g., a biliary stricture) using a wire guided catheter. Diagnosis procedures often involve the removal of a portion of suspected cancerous tissue by collecting a sample of a mucosal tissue layer off the surface of a lumen within the biliary track. Diagnosing biliary strictures, done typically with cytology brushes, can be difficult because of a low cancer sensitivity rate, which can produce a false-negative diagnosis during an endoscopic retrograde cholangiopancreatography (ERCP) procedure. Low sensitivity is frequently linked to inadequate tissue sampling, which can be a limiting factor in the detection of potential malignancy.
Many existing brushes are wire guided brushes, but brushes may be unable or have difficulty entering or crossing a stricture. For example, a tip of the brush includes radially or outward extending bristles, which may redirect or otherwise impede the delivery or movement of the brush. In some cases, a brush may be inadvertently delivered to a dilated region or pocket in front of (e.g., proximal of) a stricture. As such, the brush may not be able to collect sufficient sample for proper diagnosis.
The devices and methods of this disclosure may help to rectify one or more of the deficiencies described above or address other aspects of the art. It is to be noted, however, that the scope of subject matter of this application is defined by the features listed in the claims, and not an ability to rectify any particular deficiency.
Examples of this disclosure relate to, among other things, a cytology brush, comprising a base wire having a distal end; at least one coiled loop; and a plurality of bristles. The coiled loop is configured to at least partially surround a portion of a guide wire such that the cytology brush is longitudinally movable along and adjacent to the guide wire.
In another embodiment, the cytology brush comprises two coiled loops, and wherein each of the coiled loops is configured to surround at least a portion of the guide wire and configured to guide the cytology brush along the guide wire.
In yet another embodiment, the two coiled loops are arranged as a distal coiled loop and a proximal coiled loop, and wherein the distal coiled loop and the proximal coiled loop are physically coupled by a support bridge extending between the distal coiled loop and the proximal coiled loop.
In yet another embodiment, the base wire is a wound wire formed by two strands, and the distal coiled loop and the proximal coiled loop are each formed by two half loops formed from different ones of the two strands of the wound, two-strand wire.
In yet another embodiment, the two half loops are biased toward one another to bias the distal coiled loop and the proximal loop coiled loop in a closed position.
In yet another embodiment, the two strands of the wound, two-strand wire each comprise a leading end, and wherein the leading end of the two strands is welded to the base wire at a location proximal of the distal end of the base wire.
In yet another embodiment, the base wire includes a bend separating first and second portions, wherein the first and second portions of the wire are at least partially wound around each other, and a length of the two coiled loops are arranged in parallel along a length of the base wire and each of the two coil loops is formed from one portion of the first and second portions of the wire.
In yet another embodiment, the coiled loop extends substantially perpendicularly from the base wire.
In yet another embodiment, the coiled loop is at the distal end of the base wire.
In yet another embodiment, the coiled loop is a half loop configured to receive the guide wire at a non-parallel angle relative to the base wire.
In yet another embodiment, the base wire further includes a gap between an extreme end of a strand of the base wire, the gap being sized with respect to the guide wire such that a distance between the extreme end and the base wire allows passage of the guide wire.
In yet another embodiment, the bristles are made of rubber or silicon.
In yet another embodiment, the bristles are positioned between strands of the base wire and held in place via a friction fit.
In yet another embodiment, the bristles are made of stainless steel.
In yet another embodiment, the bristles are flexible.
In yet another embodiment, a medical device system includes a catheter comprising a lumen; a cytology brush, wherein the cytology brush includes: a base wire; and a plurality of bristles coupled to a distal portion of the base wire. The base wire and the cytology brush are moveable positioned within the lumen of the catheter, and wherein the base wire comprises at least one loop portion that is configured to at least partially surround a portion of guide wire to removably couple the base wire to the guide wire.
In yet another embodiment, the base wire includes a bend separating first and second portions, wherein the first and second portions of the wire are at least partially wound around each other and the base wire surrounds the guide wire at the at least one loop portion that includes a distal loop and a proximal loop; and the distal loop and the proximal loop are each formed by two half loops formed from one of the first or second portions of the base wire.
In yet another embodiment, each of the two first and second portions of the base wire comprise a leading end, and wherein the leading end of the two portions is welded to the base wire at a location proximal of a distal end of the base wire.
In yet another embodiment, a cytology brush system includes a guide wire; a cytology brush comprising a base wire and a plurality of bristles coupled to the base wire; and a catheter comprising a lumen for receiving the cytology brush. The base wire comprises at least one loop configured to at least partially surround the guide wire and removably couple the base wire to the guide wire for insertion of the cytology brush within a patient.
In yet another embodiment, the at least one loop is a half loop configured to receive the guide wire at a non-parallel angle relative to the base wire, and the base wire further includes a gap between an extreme end of a strand of the base wire, the gap being sized with respect to the guide wire such that a distance between the extreme end and the base wire allows passage of the guide wire.
It may be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure, as claimed.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary aspects of the present disclosure and together with the description, serve to explain the principles of the disclosure.
Reference will now be made in detail to examples of this disclosure described above and illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
The terms “proximal” and “distal” are used herein to refer to the relative positions of the components of an exemplary medical device. When used herein, “proximal” refers to a position relatively closer to the exterior of the body of a subject or closer to a user, such as a medical professional, holding or otherwise using the medical device. In contrast, “distal” refers to a position relatively further away from the medical professional or other user holding or otherwise using the medical device, or closer to the interior of the subject's body. As used herein, the terms “comprises,” “comprising,” “having,” “includes,” “including,” or other variations thereof, are intended to cover a non-exclusive inclusion, such that a device or method that comprises a list of elements does not include only those elements, but may include other elements not expressly listed or inherent thereto. Unless stated otherwise, the term “exemplary” is used in the sense of “example” rather than “ideal.” As used herein, the terms “about,” “substantially,” and “approximately,” indicate a range of values within +/−10% of a stated value.
The brush 12 (or simply “brush” 12) that includes a flexible base wire 14 with a distal end 16. A portion of the brush 12 may be configured to around or over a portion of the guide wire 11. The base wire 14 may be a brush-carrying base wire and may be formed (e.g., bent, shaped, etc.) such that it forms at least one loop structure 18 in the brush 12, for example, the loop structure 18 may include one or more coils. The base wire 14 may generally form a helical structure, which may be formed from a single or multiple wire strands (e.g., a single wire strand that is bent at an end of the wire to form two overlapping portions and those overlapping portions are wound together to form the base wire 14). In some examples, the brush 12 may include two generally parallel, wound strands or wires The base wire 14 may be made of a suitably pliable and strong material such as, for example, stainless steel, copper, nickel, and/or one or more other materials. In any of these examples, the base wire 14 of the brush 12 may extend through an endoscope or other insertion device and may be manipulable by a user (e.g., a physician controlling the insertion device) to move the base wire 14, including the brush 12, within a patient. In some aspect, the user may also control or otherwise manipulate one or more other components of the medical device system 10 (e.g., the guide wire 11 and/or the catheter 22) within the patient. In some embodiments, the brush 12 may pass in and out of the patient through the catheter 22, which may include the lumen 24. In other embodiments, the catheter 22 may be removed with the brush 12.
The brush 12 also includes a plurality of bristles 20, as shown in more detail in
For example, with the brush 12 positioned within the patient (for example, inserted into a portion of a biliary track), at least a portion of the brush 12 may be extended distally of the catheter 22, exposing at least some of the bristles 20. The bristles 20 may contact the internal tissue of the patient to collect cells and/or other tissue. For example, the brush 12 may be incrementally distally extended and/or proximally retracted, such that the bristles 20 contact and collect cells and/or other tissue. After collecting the cells and/or other tissue, the brush 12 may then be retracted proximally into the lumen 24 of the catheter 22. The brush 12 (e.g., with the catheter 22) may be retracted from the patient (e.g., with the catheter enclosing the brush 12 and its bristles 20), and the tissue may be collected from the bristles 20 and tested to make one or more diagnoses (e.g., a cancer screening, etc.)
As mentioned above, the brush 12 may be slidably couplable such that it can pass in and out of the patient through the catheter 22 (e.g., through the lumen 24 extending through a length of the catheter 22). The embodiment depicted includes the guide wire 11 outside (e.g., radially outside or external of) the catheter 22. However, in some embodiments, the catheter 22 surrounds both the guide wire 11 and the brush 12, and each of the guide wire 11, the brush 12, and the catheter 22 may be moveable with respect to the other components of the medical device system 10. The brush 12 may be inserted into the catheter 22 at a proximal end (not shown) of the catheter 22. Alternatively, the brush 12 and may be inserted into a distal end 26 of the catheter 22. If the guide wire 11 is positioned within the lumen 24 of the catheter 22, the guide wire 11 may be inserted into the catheter at the proximal end or at the distal end 26. In any of these aspects, the brush 12 (either with the guide wire 11 or separate from the guide wire 11) can pass through the catheter 22 and extend from the distal end 26 of the catheter 22 to reach a treatment site in the patient. The brush 12 and catheter 22 may pass through the patient guided by the guide wire 11. The catheter 22 may help to form or otherwise provide an atraumatic transport mechanism for the brush 12, for example, by enclosing at least a majority of the bristles 20 and can help to retain and/or protect tissue sample (e.g., cells) collected with the brush 12 as it is removed.
As shown in
In some embodiments, the half loop structures (28a, 28b and 30a, 30b) may be fitted onto and/or around the guide wire 11 outside of a patient's body and then may be manipulated such that the half loop structures, along with the brush 12, are advanced along the longitudinal length of the guide wire 11 to a treatment site (e.g., a stricture). That is, the guide wire 11 may already be positioned in the patient during a procedure, and the brush 12 (or the brush 12 and catheter 22) may be moved longitudinally along the guide wire 11 to the treatment site.
The base wire 14 may generally end at the leading edges 15, which may form a junction between the furthest possible ends of the base wire 14 and a more proximal portion of the base wire 14. In some embodiments, the leading ends 15 of the one or more of the individual strands may be fixedly coupled to the base wire 14, for example, at a weld 34. The weld 34 may help to support or otherwise maintain the structural integrity of the loop structure 18. The loop structure 18 may be offset (e.g., laterally offset) from the base wire 14 by a lateral offset portion 36. The lateral offset portion 36 may be formed from individual strands (e.g., unwound portions) of the base wire 14 and may help to provide clearance or spacing between the guide wire 11 and the base wire 14 of the brush 12. The clearance or spacing may help to ensure that the bristles 20 or other portions of the brush 12 are do not contact the guide wire 11. The clearance or spacing may also help to ensure that the guide wire 11 does not contact or otherwise interfere with the bristles 20 and/or the longitudinal motion of the brush 12, for example, as the bristles 20 of the brush 12 contact and collect tissue/cell samples. The spacing may also help to provide clearance between the catheter 22 and the guide wire 11.
As shown in
The closed loop 344 may be formed at the distal end 316 of the base wire 314 and may generally form an atraumatic tip of the brush 312. In various embodiments, the closed loop 344 may or may not surround the guide wire 11. The open loop 342 and the closed loop 344 could be formed from a single strand of the base wire 314 as shown or from separate strands of the base wire 314. Some embodiments may include a cut away portion 346, which may be formed from a single wire in the base wire 314 which may make coupling between the guide wire 11 and the base wire 314 simpler by removing a potentially interfering portion of the base wire 314
The guide wire 11 may be inserted into the patient, for example, along an outer surface of the outer sheath, such that the guide wire 11 is also advanced to the treatment site of the subject's body at a step 904. Alternatively, the guide wire 11 may be inserted into the body to the treatment site within a lumen or working channel of the outer sheath. A pushing force (e.g., in a distal direction) on a proximal portion of the guide wire 11 may be used to advance the guide wire 11 to the treatment site through the outer sheath. In some embodiments, the outer sheath may remain in the patient near the treatment site or along some portion of the path used to reach the treatment site. In other embodiments, the outer sheath may be removed from the patient once the guide wire 11 is in place near the treatment site.
The brush 12 may be slideably coupled to the guide wire 11 at a position outside the patient's body along a length of the guide wire 11 at a step 906. In some embodiments, the proximal end of the guide wire 11 may need to be threaded through one or more loops of the brush 12. For example, in embodiments having closed loops through which the guide wire 11 passes, for example, the embodiment depicted in 7A, the guide wire 11 may need to be threaded through a closed loop (such as the closed loop 752) in order for the brush 12 to be slideably attached to the guide wire 11. However, in other embodiments, such as the embodiment depicted in
At a step 908, the brush 12 is moved along a length of the guide wire 11 to the treatment site. For example, the user may push (i.e., proximally urge) a proximal end portion of the base wire 14 or a feature coupled to the base wire 14 that extends outside the patient. The user may push the base wire 14 until the brush 12 is at the treatment site and the bristles 20 are near a distal end of the guide wire and/or at the treatment site. In some embodiments, such as the embodiments depicted in
Once the brush 12 is positioned at the treatment site, the user may use the brush 12 to collect a sample in a step 910. For example, the brush 12 may be removed from the catheter 22 (e.g., by the brush 12 being distally extended from the catheter 22, the catheter 22 being proximally retracted from around the brush 12, or both) and the bristles 20 may be exposed to the treatment site to collect the sample at step 910. The sample may be collected by initiating relative motion between the catheter 22 and the brush 12 such that the brush 12 extends from the distal end 26 of the catheter 22 through the lumen 24 such that the bristles 20 may be moved into contact with tissue in the treatment site. For example, the proximal end of the base wire 14 may be pushed and/or pulled, rotated, etc. Additionally, the proximal end of the catheter 22 may be pushed and/or pulled, thereby causing the bristles 20 to move backward and/or forward on the tissue surface. The bristles 20 may brush against the treatment site, thereby scraping off cells, tissue, or other material from the treatment site. The sample may be held between or on bristles 20. In some embodiments, the bristles 20 may be designed (e.g., shape, material, etc.) such that the bristles collect relatively large amounts of material at the treatment site for the sample. For example, the bristles 20 may be designed such that the bristles have protrusions, recesses, or other features for collecting relatively large amounts of sample.
Once the tissue sample is collected on the bristles 20 of the brush 12, the user may withdraw the brush 12 in a step 912. For example, the user may position the brush 12 back into the catheter 22 and withdraw or otherwise remove the catheter 22 and the brush 12 from the patient at step 912. Positioning the brush 12 within the catheter 22 may help to isolate or otherwise protect the sample on the bristles 20 from other tissues, materials, fluids, etc. within the patient's body. Moreover, the brush 12 may be positioned within the catheter 22 by proximally retracting the brush 12 relative to the catheter 22, and/or by distally extending the catheter 11 relative to the brush 12. The brush 12 and the catheter 22 may be withdrawn or otherwise removed from the patient together. Additionally, the brush 12 may be uncoupled from the guide wire 11. For example, a user spread apart closed loops, open loops, or move the loops structures relative to the guide wire and then decouple the guide wire 11 from the one or more loop structures. The collected sample may be extracted from the brush 12 for analysis by separating the sample from the bristles 20. The extraction process may include, for example, rinsing the bristles 20 with a fluid to free the cells. Additionally or alternatively, the extraction process may include coupling the brush 12 to an electrical energy source and activating the electrical energy source to help cause the collected sample to be released or repelled from the bristles 20.
In some embodiments, the positioning of the outer sheath, guide wire 11, catheter 22, and cytology brush 12 may be monitored using an imaging device. For example, the endoscope or insertion device may include an imaging device at a distal end, such that the user(s) may observe one or more of the guide wire 11, the brush 12, or the catheter 22 via the imaging device. Alternatively or additionally, one or more of the guide wire 11, the brush 12, or the catheter 22 may include markers (e.g., radiopaque markers), such that the user(s) may observe the position of one or more of the guide wire 11, the brush 12, or the catheter 22 via an external imaging device (e.g., an X-ray).
Embodiments of the present disclosure may be applicable to various and different medical or non-medical procedures. In addition, certain aspects of the aforementioned embodiments may be selectively used in collaboration, or removed, during practice, without departing from the scope of the disclosure.
While principles of this disclosure are described herein with reference to illustrative aspects for particular applications, it should be understood that the disclosure is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, aspects, and substitution of equivalents all fall within the scope of the aspects described herein. Accordingly, the disclosure is not to be considered as limited by the foregoing description.
This application claims the benefit of priority to U.S. Provisional Application No. 63/518,342, filed on Aug. 9, 2023, which is incorporated by reference herein in its entirety.
Number | Date | Country | |
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63518342 | Aug 2023 | US |