Endoscopic suture cutter

Abstract

A method is used to cut a suture. The method includes providing a drive wire coupled to a cutter. The cutter has a first blade defining a first plane and a second blade defining a second plane non-parallel to the first plane. The first blade and the second blade define an opening. The method hooks the suture within the opening. The method cuts the suture by pulling the drive wire proximally.

Description

[Technical Field]

[0001] Priority This patent application claims priority to U.S. Provisional Patent Application No. 63 / 399,987, filed August 22, 2022, the disclosure of which is incorporated herein by reference in its entirety.

[0002] FIELD OF THE INVENTION Exemplary embodiments of the present invention relate generally to endoscopic devices, and more particularly, various embodiments of the present invention relate to a suture cutter delivered through a working channel of an endoscope. [Background technology]

[0003] Following endoscopic surgical procedures, sutures are often used to secure a perforation or wound closed and promote healing. Certain types of sutures, such as absorbable sutures, are left in place and degrade over time, while other types of sutures, such as nonabsorbable sutures, require removal at a later date. For example, sutures requiring removal include monofilament or braided sutures made of polyester or polypropylene or coated with plastic.

[0004] Endoscopic scissors are a type of surgical scissors used in endoscopic and laparoscopic medical procedures to cut tissue and sutures. Endoscopic scissors are available in many blade configurations, including curved, curved, hooked, large, small, and straight, to provide surgeons with a wide range of options to choose from when planning surgical cutting strategies. Traditional "Mayo" scissors are extremely sturdy scissors, while "Metzenbaum" scissors are scissors with smaller, more delicate blades designed for open procedures. Summary of the Invention

[0005] According to one embodiment of the present invention, a method for severing a suture includes positioning a flexible insertion tube of an endoscope inside a patient. A cutter coupled to a drive wire is moved through a working channel of the flexible insertion tube. The drive wire is configured to move the cutter along a central axis of the working channel. The cutter has a proximally facing suture-receiving portion that leads to a sharp blade. The method extends the cutter out of the working channel of the insertion tube. The suture is positioned adjacent to the sharp blade. The suture is then severed by pulling the drive wire proximally.

[0006] Pulling the drive wire proximally applies tension to the suture using the cutter, specifically one or more sharp blades of the cutter. To position the suture adjacent the sharp blades, the method can thread the suture through a suture-receiving portion. To do so, the suture-receiving portion can be positioned distal to a portion of the suture. The portion of the suture can be aligned with the suture-receiving portion. The suture-receiving portion is then moved proximally to receive the aligned portion of the suture within the suture-receiving portion.

[0007] The method can be repeated. For example, a sharp blade can be positioned adjacent to the second suture. The second suture can be severed by pulling the cutter proximally. In various embodiments, the flexible insertion tube can be angled as the cutter moves through it. Specifically, the flexible insertion tube can be angled near the distal end. For ease of movement through the insertion tube, the cutter can have a rigid longitudinal traversal length L of less than about 8 mm, preferably less than 5 mm. In some embodiments, the cutter can have a rigid longitudinal traversal length L of greater than about 0.9 mm.

[0008] In various embodiments, the cutter can be retracted within the working channel and / or delivery shaft or cutting device. The drive wire can be coupled with a retraction feature configured to position and orient the cutter to reduce or prevent interference with the delivery shaft. In various embodiments, the driving article can be coupled with an inner surface of the retraction feature. The retraction feature can include, among other things, a hypodermic tube. The hypodermic tube can be sized less than the inner diameter of the delivery shaft.

[0009] According to another embodiment, a suture cutting device includes a drive wire coupled to a cutter having a first blade defining a first plane and a second blade defining a second plane non-parallel to the first plane.

[0010] The first blade and the second blade are non-movable. Further, the first blade and the second blade may define a suture-receiving portion. The drive wire has a proximal end and a distal end, and the suture-receiving portion may face substantially the proximal end. Further, the first blade and the second blade may provide a passive cutting mechanism.

[0011] According to another embodiment, a method for severing a suture includes providing a drive wire coupled to a cutter. The cutter has a first blade defining a first plane and a second blade defining a second plane non-parallel to the first plane. The first blade and the second blade define an opening. The method hooks the suture within the opening. The method cuts the suture by pulling the drive wire proximally.

[0012] In some embodiments, the cutter may face in a substantially distally facing direction. Specifically, some embodiments may have a suture-receiving portion that faces distally. Thus, some embodiments may simply push the cutter toward the suture to cut it. Of course, some other embodiments may position the cutter in a proximally facing direction so that the cutter can be pulled to cut the suture.

[0013] According to yet another embodiment, a suture cutting system includes an endoscope having an insertion tube. The insertion tube has at least one working channel. The system includes a cutting device. The cutting device includes a handle movably coupled to a flexible drive wire. The handle is configured to move the drive wire proximally or distally within the working channel of the endoscope. A cutter is coupled to a distal end of the drive wire. Distal movement of the drive wire causes distal movement of the cutter. The cutter has a transverse longitudinal stiffness length L of less than 8 mm.

[0014] Those skilled in the art will more fully appreciate the advantages of various embodiments of the present invention from the following detailed description, discussed in conjunction with the drawings summarized immediately below. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram that schematically illustrates a patient lying on a table in a hospital environment, according to an exemplary embodiment of the present invention; [Figure 2A] 1 is a diagram illustrating a schematic diagram of an endoscope according to an exemplary embodiment of the present invention; [Figure 2B] FIG. 10 is a diagram that schematically illustrates a partially exposed view of an insertion tube, according to an exemplary embodiment. [Figure 2C] 1A and 1B are schematic diagrams illustrating a distal end of an insertion tube, in accordance with an exemplary embodiment of the present invention; [Figure 2D] 2B is a schematic diagram of the endoscope of FIG. 2A, in which the insertion tube is straight at the distal end. [Figure 2E] FIG. 2B is a schematic diagram of the endoscope of FIG. 2A, in which the insertion tube is angled near the distal end. [Figure 2F] 2B is a schematic diagram of the endoscope of FIG. 2A including an insertion tube that is curved near its distal end. [Figure 3A] 1A and 1B are schematic diagrams illustrating a cutting device according to an exemplary embodiment; [Figure 3B] FIG. 2 schematically illustrates a detailed view of a cutter according to an exemplary embodiment of the present invention. [Figure 3C] FIG. 2 schematically illustrates a detailed view of a cutter according to an exemplary embodiment of the present invention. [Figure 3D] FIG. 2 schematically illustrates a detailed view of a cutter according to an exemplary embodiment of the present invention. [Figure 3E] FIG. 2 schematically illustrates a detailed view of a cutter according to an exemplary embodiment of the present invention. [Figure 3F] FIG. 2 schematically illustrates a detailed view of a cutter according to an exemplary embodiment of the present invention. [Figure 4] 10A-10C illustrate a process for cutting a suture, according to an exemplary embodiment of the present invention. [Figure 5] 1A-1C are diagrams illustrating schematically a delivery shaft positioned within an accessory port, according to an exemplary embodiment of the present invention. [Figure 6] 6A and 6B are schematic diagrams illustrating a suture cutter transitioning from being inside the delivery shaft to extending outside the delivery shaft, according to an exemplary embodiment of the present invention. [Figure 7] FIG. 1 illustrates a perspective view of a suture cutter extended from a working channel of an endoscope, in accordance with an exemplary embodiment of the present invention. [Figure 8A] 1A-1C are schematic diagrams illustrating a suture positioned within a suture-receiving portion, according to an exemplary embodiment of the present invention; [Figure 8B] 1A-1C are schematic diagrams illustrating a suture positioned within a suture-receiving portion, according to an exemplary embodiment of the present invention; [Figure 8C] 1A-1C are schematic diagrams illustrating a suture positioned within a suture-receiving portion, according to an exemplary embodiment of the present invention; [Figure 9] 10A-10C are schematic diagrams illustrating rotation features of a cutting device, according to an exemplary embodiment of the present invention. [Figure 10]Figures 10A and 10B are schematic diagrams illustrating a process of tensioning a suture, according to an exemplary embodiment of the present invention; [Figure 11] Figures 11A and 11B are schematic diagrams illustrating the cutter being further retracted, according to an exemplary embodiment of the present invention; [Figure 12] 12A and 12B are schematic diagrams illustrating a suture being cut inside a delivery shaft, according to an exemplary embodiment of the present invention. [Figure 13] 13A and 13B are schematic diagrams illustrating a suture being cut outside of a delivery shaft, according to an exemplary embodiment of the present invention. [Figure 14] Figures 14A, 14B, and 14C are schematic diagrams illustrating a cutter interfering with a delivery shaft, a cutter not interfering with a delivery shaft, and a lead-in feature, respectively, according to an exemplary embodiment of the present invention. [Figure 15A] 1A-1C are schematic cross-sectional views of embodiments having lead-in features according to exemplary embodiments of the present invention; [Figure 15B] 1A-1C are schematic cross-sectional views of embodiments having lead-in features according to exemplary embodiments of the present invention; [Figure 15C] 1A-1C are schematic cross-sectional views of embodiments having lead-in features according to exemplary embodiments of the present invention; [Figure 15D] 1A-1C are schematic cross-sectional views of embodiments having lead-in features according to exemplary embodiments of the present invention; [Figure 15E]1A-1C are schematic cross-sectional views of embodiments having lead-in features according to exemplary embodiments of the present invention. [Figure 15F] 1A-1C are schematic cross-sectional views of embodiments having lead-in features according to exemplary embodiments of the present invention; [Figure 15G] 1A-1C are schematic cross-sectional views of embodiments having lead-in features according to exemplary embodiments of the present invention; [Figure 16] 10A-10C are schematic diagrams illustrating alternative embodiments of suture cutters, in accordance with exemplary embodiments of the present invention; [Figure 17] 10A-10C are schematic diagrams illustrating alternative embodiments of suture cutters, in accordance with exemplary embodiments of the present invention; [Figure 18] 10A-10C are schematic diagrams illustrating alternative embodiments of suture cutters, in accordance with exemplary embodiments of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0016] It should be noted that the foregoing figures, and the elements shown therein, are not necessarily drawn to consistent scale or to any scale. Unless the context suggests otherwise, like elements are designated by like numerals. The drawings are primarily for illustrative purposes and are not intended to limit the scope of the inventive subject matter described herein.

[0017] In an exemplary embodiment, an endoscope has a flexible insertion tube including a working channel through which a drive wire coupled to a suture cutter extends. The suture cutter has a relatively small profile and length to navigate through the working channel of the endoscope during a medical procedure. Advantageously, the exemplary embodiment is configured to be deployable through the working channel even when the insertion tube forms a serpentine or tortuous path. In various embodiments, the suture cutter provides a passive cutting mechanism that does not require active movement and / or independent control of one or more cutting blades. The cutter has a suture-receiving portion that connects to the cutting edge of the blade. The suture-receiving portion faces substantially proximally (also considered proximally facing) so that the physician can capture the suture by pulling the cutter proximally (pulling the cutter proximally). After the suture is captured, the physician can sever the suture by applying tension to the suture by further pulling the cutter proximally. Details of exemplary embodiments are discussed below.

[0018] In currently available flexible endoscopic suture cutters known to the inventors, the suture is cut using a traditional scissor mechanism that includes one or two movable blades. Such devices require positioning the blade next to the suture and manually controlling the blade's movement. Furthermore, cutter tools that include manually movable blades generally have long, rigid distal ends (e.g., cutter tools are approximately 2.54 cm (1 inch) long), which makes navigating the cutter through a flexible insertion tube difficult, especially when the insertion tube forms a tortuous or winding path. In contrast, the exemplary embodiment uses the cutter to capture the suture and uses tension to cut the suture, advantageously reducing the number of moving parts and providing a shorter distal end that better navigates the insertion tube.

[0019] FIG. 1 schematically illustrates a patient 12 lying on an operating or examination table in a hospital environment 10, in accordance with an exemplary embodiment of the present invention. Environment 10 may be, for example, within an endoscopy department of a hospital. The endoscopy department may include a physician 14 (e.g., a gastroenterologist or surgeon), a registered nurse 16, and various medical devices. For example, the medical devices may include an endoscope 18, a video display 20, and other equipment. Procedures performed within the endoscopy department may include gastrointestinal endoscopy (such as gastroscopy, colonoscopy, ERCP, and endoscopic ultrasound), bronchoscopy, cystoscopy, or other more specialized procedures.

[0020] 2A-2E schematically illustrate an endoscope 18 in accordance with an exemplary embodiment of the present invention. As known to those skilled in the art, a flexible endoscope 18 (e.g., a colonoscope, a gastroscope) is positioned within the body of a patient 12 through a natural orifice (e.g., the mouth, the anus) of the body. To that end, the endoscope 18 has a long, flexible insertion tube 22 that can conform to natural pathways within the body. Additionally, the endoscope 18 has multiple channels extending through the flexible insertion tube 22. One of these channels is a working channel through which a tool can be advanced to the distal end 23 of the insertion tube 22.

[0021] The endoscope 18 may be contrasted with other devices, such as a laparoscope, which are not inserted into a natural orifice of the patient 12. Instead, the laparoscope is inserted into one of several access holes made in the patient 12 during a laparoscopic procedure. Typically, three access holes are made in a laparoscopic procedure: one for the rigid endoscope and two for ports for tools such as forceps, scissors, and sutures. The laparoscope has a short, rigid, inflexible insertion tube that is passed into the body through one of the access holes. Generally, laparoscopes do not have a working channel for advancing tools therethrough. In contrast, the insertion tube 22 of the endoscope 18 (e.g., colonoscope, gastroscope) is flexible and has a working channel for advancement through a natural orifice in the body. Various embodiments may be used with various scopes, such as a laparoscope. However, a preferred embodiment uses a flexible insertion tube 22.

[0022] The endoscope 18 has a control section 26 to assist in guiding the insertion tube 22 through the patient's 12 body passages (e.g., the tortuous digestive tract). To that end, the endoscope 18 includes control dials 26 that allow control of the position and orientation of the insertion tube 22 (e.g., turning the distal end 23 up or down and left or right). Like many endoscopes, the endoscope 18 may have multiple imaging controls, such as an image freeze button and an image capture button. There may also be a control chromoendoscopy button that can change the color of the image in the display 20. The control section 26 may also include a suction button 28 and an air / water button 30. The endoscope 18 may be connected to a light source via a light guide 31, an air source via an air supply connector 32, a water source via a water supply connector 34, and a suction source via a suction connector 36. Thus, light, air, water, and / or suction may be delivered through the various channels described above, through umbilical cord 35, and to distal end 23 of insertion tube 22.

[0023] Water, air, suction, and other functions may be selectively applied at the distal end 23 through separate channels within the insertion tube 22. For example, a user may press a water button 30 to selectively spray water out of the distal end 23. To do so, water is drawn from an external water source through a water supply connector 34, passes through an umbilical cord 35 of the endoscope 18, and down the insertion tube 22 and out of the distal end 23. A similar process occurs for other functions, including light and suction. Each of these functions may have a dedicated channel within the endoscope 18.

[0024] FIG. 2B schematically illustrates a partially exposed view of the insertion tube 22 according to an exemplary embodiment. The insertion tube 22 has multiple channels 38-41 and wires 42-45 configured to provide various functions for the endoscope 18. For example, the insertion tube 22 includes a biopsy channel 38, an air channel 39, a water channel 40, and a water jet channel 41. The insertion tube 22 may also include, among other components, a light guide fiber 42, a wire 43 for adjustable stiffness, an angulation wire 44, and a CCD signal wire 45. These channels 38-41 and wires 42-45 are located within the housing of the insertion tube 22. The housing of the insertion tube 22 may include an outer polymer top coat 46 and a base layer. Beneath the polymer top coat 46 may be a stainless steel wire mesh 47, along with an outer spiral metal band 48 and an inner spiral metal band 49.

[0025] FIG. 2C schematically illustrates the distal end 23 of the insertion tube 22 with a tool 50 extending out of the working channel 38, according to an exemplary embodiment of the present invention. The tool 50 may be positioned within the working channel 38 by passing through the accessory port 37 (shown in FIG. 2A). For example, FIG. 2C schematically illustrates a biopsy forceps 50 extending out of the working channel 38. Various embodiments use a cutting device 54 to deliver a suture cutter 64 through the working channel 38. The cutting device 54 may also be referred to as a cutter delivery device 54.

[0026] FIG. 2D schematically illustrates the endoscope of FIG. 2A in a substantially straight position near the distal end 23 of the insertion tube 22. FIG. 2E schematically illustrates the endoscope of FIG. 2A in a position where the position and orientation of the insertion tube 22 have been adjusted (e.g., angled). Specifically, the control section 26 is used to bend the distal end 23. In practice, the physician 14 controls the bending of the insertion tube 22 to properly orient the distal end 23 within the patient 12 during a procedure. For example, the insertion tube 22 can be bent in various ways to traverse the digestive tract. When the distal end 23 is near a desired location, the orientation of the distal end 23 is manipulated (e.g., to obtain a particular biopsy specimen, capture a particular suture, etc.). Once the distal end 23 is properly oriented, the tool 50 can be extended out of the working channel 38. However, if the distal end 23 of the tool 50 (e.g., a cutter, biopsy forceps, scissors, etc.) is rigid, it can be difficult to advance the tool 50, especially when the distal end of the endoscope 18 is angled as shown in Figures 2E and 2F.

[0027] FIG. 2F schematically illustrates the endoscope of FIG. 2A with the curved portion 21 of the insertion tube 22 near the distal end 23. In some use cases, the insertion tube 22 may be curved significantly, particularly near the distal end 23, to achieve a desired orientation relative to the patient 12 and / or the suture 68. Once the desired orientation is achieved, one or more tools 50A and 50B may be advanced out of one or more working channels 38. For example, as shown in FIG. 2F, the tools 50 may be, among others, endoscopic scissors 50B and an endoscopic snare 50A. However, various embodiments may advance other tools 50, such as biopsy forceps and / or endoscopic clips, out of the working channel 38. Each of the tools 50 may be said to have a longitudinal transverse stiffness length L when the tool 50 is advanced through the insertion tube 22 and / or out of the working channel 38. However, as discussed below, some tools 50 may have a negligible stiffness length.

[0028] For example, endoscopic scissors 50B has a longitudinal transverse stiffness length L when advanced across insertion tube 22 and out of working channel 38. The longitudinal transverse stiffness length L of scissors 50B is determined by the stiffness length of tool 50 as it advances through insertion tube 22. For example, the transverse length L of scissors 50B is determined when the blades are closed (because scissors 50B advances through insertion tube 22 with the blades closed).

[0029] As another example, snare tool 50A is another tool 50 that can be used in various embodiments. Snare tool 50A includes a flexible snare portion 68 extending from a flexible delivery housing 69. The snare portion 68 is flexible during normal operation of endoscope 18 and therefore includes only a small amount of rigidity. The snare portion 68 extends from delivery device 69 after delivery device 69 has been extended from working channel 38. Because delivery device 69 is flexible, delivery device 69 has only a small amount of rigidity as it traverses through insertion tube 22. In other words, delivery device 69 and snare portion 68 bend to accommodate the shape of insertion tube 22 as they advance inside insertion tube 22. Therefore, during normal use, physician 14 does not need to adjust the shape of insertion tube 22 to allow passage of snare tool 50A.

[0030] As yet another example of a tool 50, some embodiments may include a suture cinch tool 50, such as that described in US Patent Application No. 17 / 991,526, which is incorporated herein by reference.

[0031] Those skilled in the art will appreciate that a longer stiffness length L makes it more difficult for the tool 50 to advance through the flexible insertion tube 22 and / or exit the distal end 23. Depending on the curvature / angulation of the insertion tube 22, some longer stiffness lengths L may be impossible to advance through the insertion tube 22 (e.g., out of the distal end 23). Accordingly, various embodiments advantageously provide a small stiffness length L for the tool 50. For example, the stiffness length L of the endoscopic suture cutter 64 is small (about 0.1 inches to about 0.3 inches), allowing for easier device advancement and better access when the distal end 23 of the endoscope is not in a straight orientation. This contrasts with the stiffness length L of endoscopic scissors (about 0.5 inches to about 1.0 inches). If the distal end 23 of the endoscope 18 is angled, it may be difficult or impossible to advance scissors inside the working channel 38 in the angled region. Instead, the practitioner 14 needs to straighten the tip of the endoscope 18 in order to advance scissors inside the working channel. The illustrative embodiment allows the practitioner 14 to advance the cutter 64 inside the working channel 38 in the angled region.

[0032] FIG. 3A schematically illustrates a cutting device 54 according to an exemplary embodiment. The cutting device 54 includes a cutter deployment system 62 configured to be positioned within the insertion tube 22 and to move a cutter 64 therethrough. As described below, the cutter deployment system 62 includes, among other things, a delivery shaft 74, a drive wire 60 within the delivery shaft 74, and a cutter 64 coupled to the drive wire 60. The cutter deployment system 62 is controlled from outside the insertion tube 22. To that end, the cutting device 54 includes a handle slider 56 having an opening configured to receive the thumb of the practitioner 14. During use, the handle slider 56 slides along a handle frame 58. Movement of the handle slider 56 relative to the handle frame 58 moves the drive wire 60 inside the delivery shaft 74 proximally or distally along the delivery shaft 74. As shown in FIG. 9 , the handle frame 58 and the handle slider 56 can be rotated to rotate the cutter 64.

[0033] In various embodiments, the drive wire 60 (also referred to as the puller wire 60) may be movable axially (e.g., substantially along A1) within the delivery shaft 74. The axis A1 is a central longitudinal axis extending through the working channel 38. The drive wire 60 may be a long puller wire 60 supported inside the delivery shaft 74. In some embodiments, the drive wire 60 may include a long puller wire 60, such as a solid wire, a stranded wire, or a combination of both. In some embodiments, the drive wire 60 may include a spring guide 65 for support and / or a long puller wire 60 inside the delivery shaft 74. The spring guide 65 may be inside the delivery shaft 74 and support the puller wire 60. In some embodiments, the delivery shaft 74 may include a long catheter without a spring guide 65. The puller wire 60 may have a small diameter and lack its own structural support. In various embodiments, delivery shaft 74 or / and spring guide 65 provide structural support to puller wire 60 (such as while being threaded through working channel 38).

[0034] In various embodiments, the puller wire 60 is inside the delivery shaft 74 (e.g., a catheter). Thus, some embodiments may not include a Bowden coil 65. Some embodiments may use a coil instead of a catheter, or may use both a coil and a jacket. As previously mentioned, the puller wire 60 has a small diameter and generally does not have its own structural support. Thus, in various embodiments, the puller wire 60 may be supported by the delivery catheter, delivery coil, and / or delivery coil, including the jacket (catheter).

[0035] Although axis A1 is shown as a straight axis, it should be understood that in various embodiments, the delivery shaft 74 is configured to bend and / or twist in a manner similar to the insertion tube 22, and thus axis A1 can also be curved, bent, and / or twisted. Thus, in various embodiments, moving the drive wire 60 and / or cutter 64 along axis A1 may not be a linear axial motion. Furthermore, in some embodiments, the distal end of the drive wire 60 can be bent such that the drive wire 60 forms a central cutter axis B1 that diverges from the central axis A1 of the insertion tube 22. When the cutter axis B1 diverges from the central axis A1, the pull wire 60 can be pressed against the inner diameter of the delivery shaft 74. This provides maximum space for the cutter 64 to move proximally and distally within the delivery shaft 74. Furthermore, the diverging cutter axis B1 allows the cutter 64 to rotate in an arc as it is extended distally. This allows the cutter 64 a larger reach area to capture the suture 78 .

[0036] 3B-3F schematically illustrate detailed views of cutter 64 in accordance with an exemplary embodiment of the present invention. Cutter 64 is configured to cut one or more sutures placed within patient 12 (e.g., in the digestive tract). To that end, cutter 64 has a suture-receiving portion 76 configured to guide or direct the sutures to one or more sharp blades 70. In FIG. 3B, cutter 64 has four sharp blades 70. Two of the sharp blades 70 are used to cut the sutures. The sharp blades 70 may be part of cutting blades 72A and 72B, respectively. In some embodiments, first cutting blade 72A may be planar with body 80 of cutter 64. For example, cutting blade 72A may be formed from body 80. Second cutting blade 72B may be out of the plane of first cutting blade 72A and / or body 80 (e.g., biased upward) such that suture-receiving portion 76 is formed by blades 72A and 72B. In some embodiments, first blade 72A defines a first plane and second blade 72B defines a second plane that is non-parallel to the first plane. In some embodiments, first blade 72A, second blade 72B, and body 80 may all have substantially non-parallel planes (as shown in FIGS. 3E and 3F ).

[0037] Once the suture 78 is positioned within the suture-receiving portion 76, the cutter 64 may be pulled proximally to effect severing of the suture 78. Specifically, the suture 78 may be severed by applying tension to the suture 78 with the blades 72A and 72B (e.g., by the user pulling on the handle 56 to move the wire 60 coupled with the cutter 64 proximally). The sharp blades 72A and 72B press against the suture 78 to sever the suture 78.

[0038] While various embodiments show and describe two blades 72A and 72B, it will be understood that this is not intended to limit various embodiments of the present invention. Some embodiments may have only a single blade 72 including a sharp blade 70. For example, some embodiments may have only a planar blade 72A. Some other embodiments may have only an out-of-plane blade 72B. Embodiments including a single blade 72 may still form a suture-receiving portion 76 (e.g., using a second blunt edge instead of the second sharp blade 70). For example, some embodiments may include one or more arc-shaped or semicircular blades 72. Thus, discussion of a single blade 72 or multiple blades 72 is not intended to limit various embodiments of the present invention. For example, the suture-receiving portion 76 may be formed by one or both of the blades 72A and 72B.

[0039] Cutter 64 advantageously operates as a passive tension cutter, meaning that no user control or active movement of blade 72A at blade 72B is required to cut suture 78. Instead, tensioning suture 78 toward sharp blade 70 severs suture 78. In various embodiments, out-of-plane blade 72B can be upwardly biased (e.g., resilient) or rigidly formed.

[0040] In various embodiments, the cutter 64 may be formed (e.g., stamped, electro-discharge machined) from a thin sheet of material (e.g., metal or plastic). In some embodiments, the thickness T of the cutter 64 material is 1 mm or less (e.g., T1 and T2 are each less than 1 mm). Additionally, the out-of-plane blades 72B may cause the cutter 64 to have an overall height H that exceeds the thickness T. In various embodiments, the cutter height H is between about 1.3 mm and 3.5 mm. The overall width W of the cutter 64 may be between about 1 mm and about 2 mm. The overall rigid length L of the cutter 64 may be between about 4 mm and about 8 mm. The outer edges 75 (e.g., distal or proximal edges) of the cutter 64 are preferably blunt or rounded to prevent accidental cuts to the patient 12. An opening O in the suture-receiving portion 76 (e.g., formed by the two blades 72) allows the cutter 64 to grasp and receive a suture 78. If the opening O is too small, it will be difficult to capture or properly position the suture 78 between the two blades 72. If the opening O is too large, it will be difficult to retract the blades 72 into the delivery shaft 74 (see, e.g., FIG. 14A). The opening O is preferably between 0.9 mm and 3.1 mm. For clarity, the range between endpoints X and Y will be considered to include endpoints X and Y.

[0041] In various embodiments, non-movable cutting edges 70A and 70B meet at cutting point 71, which provides efficient severing of suture 78, as opposed to typical scissor-style cutters in which two opposing blades move relative to one another to create a movable cutting point. In various embodiments, the two blades 72A and 72B do not move to cut. Blade 72 is preferably sufficiently stiff and short so that blade 72 does not move when used regularly to cut suture 78. Thus, blades 72A and 72B may be considered static blades 72A and 72B. Although static blades 72A and 72B may be formed from a material that may be deformable or malleable under the application of sufficient force (i.e., under non-normal use), blades 72A and 72B are still considered static / non-movable during normal use by physician 14 (e.g., when applying sufficient force to cut suture 78).

[0042] In various embodiments, depending on the thickness of the suture 78, the suture 78 may be severed in a cutting region 73 formed between the cutting edges 70A and 70B of the two blades 72. In some embodiments, the suture 78 may reach the cutting point 71. However, in some other embodiments, the suture 78 may be severed within the cutting region 73 formed by the blades 72.

[0043] 4 illustrates a process 400 for cutting suture 78, in accordance with an exemplary embodiment of the present invention. It should be noted that this process has been simplified from a longer process that would typically be used to cut suture 78. Thus, process 400 for cutting suture 78 would have many steps that one skilled in the art would use. Additionally, some of the steps may occur in a different order than shown. Additionally, or alternatively, some of the steps may occur simultaneously. Thus, one skilled in the art can modify process 400 as needed.

[0044] Process 400 begins at step 402, in which physician 14 sutures a perforation inside patient 12. For example, during a medical procedure, physician 14 may perform a biopsy from patient 12 by removing a polyp using a biopsy tool 50 (e.g., biopsy forceps). Biopsy tool 50 may be placed within the working channel 38 of endoscope 18. Physician 14 may then use an optional suturing tool 50 to suture the perforation. In various embodiments, the suturing tool may be attached to the outside of distal end 23 of insertion tube 22. Various embodiments of endoscope 18 may include one or more working channels 38.

[0045] The process of suturing a perforation is known in the art and therefore will not be described in greater detail here. Generally, the process involves grasping tissue near the perforation (e.g., using tissue grasping tool 50), retracting the tissue, passing a needle coupled to suture 78 through the tissue, and repeating stitches as desired. Thus, in the above example, suture 78 has two ends: a first end coupled to the needle and a second, free end. Various embodiments may cinch the free end of the suture and / or the first end coupled to the needle together or separately. In some other embodiments, the suture is coupled to a needle that is part of a needle assembly (e.g., which passes through and grasps the tissue). Thus, the suture may be considered to have a single free end and a second, tethered end. The suture may be formed of any material commonly used for surgical sutures, such as stainless steel, nitinol, nylon, braided polyester, polypropylene, and / or silk. Some may also be used to cut a suture 78 that has two free ends.

[0046] The process proceeds to step 404 with providing an endoscopic suture cutting device 54, such as the device 54 shown in Figures 3A-3B. The device 54 may be provided to the physician 14 during and / or after a medical procedure, such as a polypectomy. The exemplary embodiment works with various sutures and / or endoscopic suturing devices. Advantageously, the suture cutting device 54 may be used to cut sutures that have been previously applied to the patient 12 (e.g., to a perforation) using an integrated or separate stitching tool.

[0047] The process proceeds to step 406 with positioning the cutter deployment system 62 within the working channel 38 of the endoscope 18. To remove sutures 78 within the digestive tract, the patient 12 may be intubated with the endoscope 18. After positioning the endoscope 18 inside the patient 12 and placing the sutures 78 to be cut, the practitioner 14 inserts the deployment system 62 into the accessory port 37 of the endoscope 18. Alternatively, the deployment system 62 may be positioned within the accessory port 37 prior to positioning the endoscope 18.

[0048] Specifically, the distal end of the delivery shaft 74 may be initially positioned within the accessory port 37 of the endoscope 18. Figure 5 schematically illustrates the cutter deployment system 62 positioned within the accessory port 37. Specifically, the delivery shaft 74 is inserted into the accessory port 37. The delivery shaft 74 may advantageously bend in a manner that corresponds to the shape of the insertion tube 22.

[0049] In step 408, the suture cutter 64 is extended from the working channel 38 of the endoscope 18. Figures 6A-6B schematically illustrate the suture cutter 64 transitioning from being inside the delivery shaft 74 to extending outside the delivery shaft 74, in accordance with an exemplary embodiment of the present invention.

[0050] Specifically, Figure 6A shows the cutter 64 inside the delivery shaft 74. From the perspective of the practitioner 14, the handle 56 is in a retracted position. To extend the suture cutter 64 from the working channel 38, the handle 56 is moved forward after the delivery shaft 74 is positioned outside the working channel 38 of the endoscope 18, as shown in Figure 6B.

[0051] 7 shows a perspective view of a suture cutter 64 extended from the working channel 38 of the endoscope 18, in accordance with an exemplary embodiment of the present invention. In contrast to many prior art cutting tools, in various embodiments of the cutter 64, the suture-receiving portion 76 defines an opening or gap that faces substantially proximally (i.e., facing the working channel 38 and / or distal end 23 of the endoscope 18).

[0052] In some embodiments, the puller wire 60 can be configured to cause the cutter 64 to extend straight out from the delivery shaft 74. However, in some other embodiments, as shown in FIG. 7 , the puller wire 60 can be configured to bend as it exits the delivery shaft 74. Thus, the central axis B1 of the cutter 64 can form an axis B1 that diverges from the central axis A1 by an angle Θ1. In various embodiments, the angle Θ1 can be between about 5 degrees and about 30 degrees, or between about 10 degrees and about 20 degrees.

[0053] Advantageously, the proximally facing suture-receiving portion 76 allows the practitioner 14 to hook the suture 78 through the suture-receiving portion 76 and cut the suture 78 by simply retracting the cutter 64 (e.g., by pulling the drive wire 60 proximally). Furthermore, the cutter 64 does not require independent, active control of the blades 72A and 72B. Instead, as described below, the suture 78 is positioned within the suture-receiving portion 76 and then severed by the blade 72 using tension on the suture 78. Because there is no movement of the blades 72A and 72B relative to one another, no pivot mechanism is required. However, some embodiments may still have some biasing / movement of the passive blade 72. Accordingly, the exemplary embodiment provides a passive / static cutting mechanism using a passive, planar blade 72A and / or an out-of-plane (e.g., biased) blade 72B. Thus, the cutter 64 is advantageously much shorter and thinner than many prior art cutters and easily advances through the insertion tube 22 .

[0054] After the suture cutter 64 is extended, the suture 78 is positioned within the suture-receiving portion 76 in step 410. FIGS. 8A-8C schematically illustrate the suture 78 being positioned within the suture-receiving portion 76, in accordance with an exemplary embodiment of the present invention. As shown in FIGS. 8A-8B, the cutter 64 is advanced until it is located distal to the suture 78. A portion of the opening of the suture-receiving portion 76 is aligned with at least a portion of the suture 78 (as represented by the dashed line in FIG. 8). The handle 56 may be manipulated until the suture 78 is positioned (e.g., hooked) within the suture-receiving portion 76. FIG. 8C schematically illustrates a close-up view of the suture 78 positioned within the suture-receiving portion 76, in accordance with an exemplary embodiment of the present invention. At this point, the suture 78 can be said to be "captured" or "hooked" by the cutter 64.

[0055] In various embodiments, the cutter 64 may need to be rotated to properly align the opening in the receiving portion 76 with the suture 78. FIG. 9 schematically illustrates the rotation feature of the cutting device 54 in accordance with an exemplary embodiment of the present invention. As previously described, the cutting device 54 may be coupled to the endoscope 18. In an exemplary embodiment, the handle 56 may be rotated to rotate the cutter 64. Thus, the receiving portion 76 is advantageously rotatable to allow for easy alignment and capture of the suture 78. For example, rotation allows for repositioning the receiving portion 76 to an ideal position for capturing the suture 78. To that end, in various embodiments, the puller wire 60 is coupled to the handle slider 56, and the delivery shaft 74 is coupled to the coupler 61 (as shown in FIG. 3A ). This allows for relative rotation of the drive wire 60, and therefore the cutter 64, with respect to the flexible tubing 22 and the delivery shaft 74.

[0056] In various embodiments, handle 56 is external to accessory port 37 and is operated by physician 14. To fit through working channel 38, delivery shaft 74 is preferably long for endoscopic procedures (e.g., about 150 cm to about 250 cm).

[0057] The process then proceeds to step 412 of applying tension to cut the suture 78 with the suture cutter 64. FIGS. 10A-10B schematically illustrate the process of applying tension to the suture 78, according to an exemplary embodiment of the present invention. FIG. 10B shows a detailed view of FIG. 10A. In various embodiments, tension can be applied by retracting the suture cutter 64. To do so, the handle 56 is pulled proximally (as represented by the arrow). FIGS. 10A-10B schematically illustrate the suture cutter 64 being retracted with the captured suture 78, according to an exemplary embodiment. As the suture cutter 64 retracts, the suture 78 is tensioned. Once sufficient tension is applied, the suture 78 is cut by the blade 72A or 72B. Depending on the type of suture 78, additional tension may be required. The captured suture 78 can be further tensioned by further proximally pulling the suture cutter 64 and / or the entire cutter deployment system 62. Figures 11A-11B schematically show the cutter 64 being further retracted, according to an exemplary embodiment.

[0058] Various embodiments advantageously sever the suture 78 by pulling substantially proximally. Because the practitioner 14 pulls proximally (away from the tissue) to sever the suture 78, the exemplary embodiments advantageously provide additional safety compared to traditional endoscopic scissors. A practitioner 14 using endoscopic scissors cuts the suture toward the tissue (distal), which can undesirably cut the tissue (e.g., accidentally if the tip of the blade is near the tissue). In the exemplary embodiments, the practitioner 14 cuts the suture 78 by pulling away from the tissue (i.e., by pulling the cutter proximally), which reduces the likelihood of cutting and injuring the tissue.

[0059] Based on testing, the inventors have determined that the suture 78 will cut on the outside or inside of the delivery shaft 74 when the proper amount of tension is applied. Depending on the type of suture 78 (e.g., smaller sized sutures cut more easily than larger sized sutures) and the amount of suture under tension during the procedure, the suture 78 may cut before it is retracted into the delivery shaft 74, or the handle may need to retract the blade 72 and suture 78 further into the delivery shaft 74 in order to apply more tension to the suture and cut it. The further the cutter 64 is retracted into the delivery shaft 74, the more tension is applied to the suture 78.

[0060] However, in some embodiments, the cutter 64 may face substantially in a distal direction, such that the suture-receiving portion 68 faces substantially distally. Thus, some embodiments may simply push the cutter 64 toward the suture 78 (e.g., by pushing the handle distally) to cut the suture 78. Of course, some other embodiments may position the cutter 64 in a proximal-facing orientation so that the cutter 64 can be pulled to cut the suture 78.

[0061] 12A-12B schematically illustrate a suture 78 being cut inside a delivery shaft 74, according to an exemplary embodiment of the present invention. Figures 13A-13B schematically illustrate a suture 78 being cut outside a delivery shaft 74, according to an exemplary embodiment of the present invention.

[0062] The process proceeds to step 414, which asks whether there are more sutures to be cut. If yes, the process returns to step 410, which positions the suture 78 within the suture-receiving portion 76 of the cutter 64. In some embodiments, the suture cutting device may be removed from the working channel 38, and endoscopic scissors may be used to cut the suture 78. The process 400 then repeats substantially as described above until the suture 78 is cut.

[0063] If there are no more sutures 78 to cut, the process proceeds to step 416, where the suture cutter 64 is removed from the endoscope 18. To remove the suture cutter 64, the suture cutter 64 is retracted back into the delivery shaft 74 and through the insertion tube 22. The inventors have determined that removing the suture cutter 64 can be difficult in various embodiments due to interference with the delivery shaft 74. Figures 14A-14B schematically show distal end views of the cutter 64 being retracted toward the delivery shaft 74. Figures 14A and 14B show two different results of retracting the blade 72 toward the delivery shaft 74.

[0064] As shown in FIG. 14A , the cutter 64, particularly the biased blade 72B, may interfere with and thereby catch on the delivery shaft 74 (e.g., particularly at the maximum height H of the cutter 64). The delivery shaft 74 may, for example, become undesirably positioned within the receiving portion 76. This may require further manipulation by the practitioner 14 to remove the shaft 74 from the receiving portion 76 and then attempt to properly position the cutter 64 within the lumen of the shaft 74, as shown in FIG. 14B . Specifically, FIG. 14B shows that there is no interference between the blade 72B and the inner wall 74A of the delivery shaft 74.

[0065] In various embodiments, the distal end of the puller wire 60 is bent to facilitate retraction of the blade 72 into the delivery shaft 74. Specifically, the bend reduces the likelihood that the blade 72 will catch on the delivery shaft 72 as it is pulled toward it.

[0066] FIG. 14C schematically illustrates a retraction feature 82 of a cutting device 54 according to an exemplary embodiment. The retraction feature 82 is configured to position and orient the cutter 64 so that there is minimal or no interference between the one or more blades 72 and the delivery shaft 74 when the cutter 64 is retracted into the delivery shaft 74 (e.g., as shown in FIG. 14B ). In some other embodiments, the retraction feature 82 comprises a hypodermic tube 82 (e.g., having a length 83 of about 5 mm to about 9 mm) that is coupled (e.g., welded, glued, or integrally formed) to the wire 60 near its distal end to approximate or press the wire 60 against the inner wall 74A of the delivery shaft 74. This ensures that there is adequate space for the blades 64 to retract inside the delivery shaft 74 (e.g., a catheter). Thus, the retraction feature 82 minimizes or eliminates interference between one or more blades 72A and the delivery shaft 74. To that end, the retraction feature 82 may be sized slightly smaller than the inner diameter of the delivery shaft 74 (to push the wire 60 toward the inner wall of the delivery shaft 74 without providing excessive resistance to movement of the feature 82).

[0067] In some embodiments, the puller wire 60 may be coupled to the inner or outer surface of the hypotube 82 such that the puller wire 60 is held against or adjacent the inner surface 74A of the delivery shaft 74. The retraction feature 82 may be rigidly secured to the puller wire 60 such that the cutter 64 is rotationally and movably secured to the retraction feature 82. Thus, as the cutter 64 moves proximally or distally, the retraction feature 82 similarly moves proximally or distally. Similarly, as the cutter 64 is rotated, the retraction feature 82 also rotates. The retraction feature 82 is preferably coupled to the puller wire 60 such that the cutter 64 is oriented and positioned to avoid interference with the shaft 74.

[0068] 15A-15G schematically illustrate various cross sections of various embodiments having a lead-in feature 82. Specifically, the cross sections show the cutter 64 and the delivery shaft 74. It should be understood that the lead-in feature 82 is not shown in the cross sections because the lead-in feature 82 may be located proximal to the cutter 64 (see, e.g., FIG. 14C).

[0069] As an example, an imaginary plane P1 may be drawn through the maximum diameter of the delivery shaft 74 and the axis of rotation 88 of the cutter 64. An imaginary plane P2 may also be defined along the maximum height of the cutter 64. An angle α1 is defined between P1 and P2. In various embodiments, certain angles α1 orient the cutter 64 so that there is no interference with the delivery shaft 74 (e.g., shown in FIGS. 15A-15C). However, certain other angles α1 orient the cutter 64 so that there is interference with the delivery shaft 74 (e.g., shown in FIGS. 15D-15G). In some embodiments, angle α1 is preferably selected so that interference between the maximum height H of the cutter 64 and the shaft 74 is minimized or eliminated.

[0070] 15A-15G illustrate various angles for the puller wire 60, it should be understood that the puller wire 60 may be coupled at various locations along the cutter 64 (e.g., at different ends of the cutter 64, on opposite sides, etc.). However, the exemplary embodiment advantageously couples the wire 60 off-center from the cutter 64 so that the suture 68 can easily enter the receiving portion 76.

[0071] Additionally, the dimensions of the cutter 64, puller wire 60, and / or delivery shaft 74 may differ from the examples shown herein. Thus, various embodiments are not limited to the angles described herein. These examples are provided merely to illustrate particular orientations and positions that may be possible using the retraction feature 82. One skilled in the art can determine how to appropriately size and orient the cutter 64, puller wire 60, and retraction feature 82 relative to one another to ensure that the cutter 64 has limited or no interference with the delivery shaft 74 during retraction. Process 400 then ends.

[0072] 16-18 schematically illustrate an alternative embodiment of a suture cutter 64, in accordance with an exemplary embodiment of the present invention. FIG. 16 schematically illustrates a suture cutter 64 having two planar blades 72. A receiving portion 76 may be formed in part from the drive wire 60.

[0073] 17 schematically illustrates a suture cutter 64 having a single blade 72. The cutting edge 70 may face substantially proximally. Similar to FIG. 16, the receiving portion 76 may be formed from the drive wire 60.

[0074] 18 schematically illustrates the suture cutter 64 of FIG. 17 having a pre-receiving portion 84. The pre-receiving portion 84 may be formed from the drive wire 60 or may be formed separately. The pre-receiving portion 84 allows the practitioner 14 to initially capture the suture 78 by pushing the cutter 64 distally (e.g., substantially along axis A1). The suture 78 can then be guided into the suture-receiving portion 76, which leads to the blade 72, by aligning the suture 78 with the receiving portion 76 and pulling the cutter 64 proximally, as represented by the movement of the arrow.

[0075] It will be apparent to those skilled in the art that the exemplary embodiment provides several advantages to the physician 14 and the patient 12. Specifically, the exemplary embodiment advantageously provides a cutter 64 with a small, rigid profile (e.g., length L) that allows for easy movement through the angled insertion tube 22. Additionally, the exemplary embodiment provides a reduced-profile device without a movable blade 72. Thus, an active control mechanism for the blade 72 (e.g., a control mechanism for rotating the blade around a pin as in traditional scissors) is not required. Furthermore, due to the orientation of the cutter 64 relative to the device 54, the exemplary embodiment allows the physician 14 to sever the suture 78 using a pulling motion. This pulling motion can be performed using the same handle 56 used to position the cutter 64. The simplified hooking and cutting motion using a single handle 56 advantageously simplifies the medical procedure for the physician 14.

[0076] While various inventive embodiments have been described and illustrated herein, those skilled in the art will readily envision various other means and / or structures for performing the functions described herein and / or obtaining one or more of the results and / or advantages described herein, and each of such variations and / or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on the specific application for which the teachings of the present invention are used. Those skilled in the art will recognize many equivalents to the specific inventive embodiments described herein, or will be able to ascertain such equivalents using no more than routine experimentation. It is therefore to be understood that the foregoing embodiments have been presented by way of example only, and that, within the scope of the appended claims and their equivalents, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and / or method described herein. Furthermore, any combination of two or more such features, systems, articles, materials, kits, and / or methods is within the inventive scope of the present disclosure, provided that such features, systems, articles, materials, kits, and / or methods are not mutually inconsistent.

[0077] Various inventive concepts may be embodied as one or more methods, examples of which are provided. The actions performed as part of a method may be ordered in any suitable manner. Thus, embodiments may be constructed in which actions are performed in an order different from that illustrated, and such embodiments may include performing some actions simultaneously, even though shown as sequential actions in the exemplary embodiments.

[0078] While the subject matter contained herein has been described in detail for purposes of illustration, it should be understood that such detail is for that purpose only, and that the present disclosure is not limited to the disclosed embodiments, but on the contrary, is intended to cover modifications and equivalent arrangements within the spirit and scope of the appended claims. For example, it should be understood that the present disclosure contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.

[0079] While the foregoing discussion discloses various exemplary embodiments of the present invention, it will be understood that those skilled in the art could make various modifications which would obtain some of the advantages of the present invention without departing from the true scope of the invention.

Claims

1. 1. A method of cutting a suture, comprising: Positioning a flexible insertion tube of an endoscope inside a patient; moving a passive cutter coupled to a drive wire through a working channel of the flexible insertion tube, the drive wire configured to move the cutter along a central axis of the working channel, the cutter having a proximally facing suture-receiving portion leading to a sharp blade; extending the cutter out of the working channel of the insertion tube; positioning the sharp blade adjacent to a suture; severing the suture by pulling the drive wire proximally; A method comprising:

2. Positioning the suture adjacent the sharp blade Threading the suture through the suture-receiving portion. The method of claim 1 , comprising:

3. threading the suture through the suture-receiving portion; moving the suture-receiving portion distal to a portion of the suture; aligning the portion of the suture with the suture-receiving portion; moving the suture-receiving portion proximally to receive the aligned portion of the suture within the suture-receiving portion. The method of claim 2 , comprising:

4. The method of claim 1 , wherein the cutter has a longitudinal transverse stiffness length L of less than about 8 mm.

5. positioning the sharp blade adjacent to a second suture; severing the second suture by pulling the cutter proximally; The method of claim 1 , further comprising:

6. The method of claim 1 , wherein the flexible insertion tube is angled near the distal end.

7. The method of any one of claims 1 to 6, wherein the cutter has at least one blade that forms a suture-receiving portion.

8. The method of claim 1 , further comprising the step of retracting the cutter into the working channel.

9. 10. The method of claim 8, further comprising retracting the cutter into a delivery shaft, wherein the drive wire is coupled with a retraction feature configured to position and orient the cutter to reduce or prevent interference with the delivery shaft.

10. A drive wire coupled to the cutter Equipped with A suture cutting device, wherein the cutter has at least one blade defining a suture receiving portion.

11. The suture cutting device of claim 10, wherein the cutter has a first blade defining a first plane and a second blade defining a second plane that is non-parallel to the first plane.

12. The suture cutting device of any one of claims 1 to 11, wherein the first blade and the second blade are non-movable.

13. The suture cutting device of claim 1 , wherein the drive wire has a proximal end and a distal end, and the suture receiving portion faces substantially toward the proximal end.

14. The suture cutting device of any one of claims 1 to 13, wherein the cutter has a transverse longitudinal stiffness length L of less than about 8 mm.

15. The suture cutting device of any one of claims 1 to 14, further comprising a lead-in feature configured to position and orient the cutter to reduce or prevent interference with the delivery shaft.

16. The suture cutting device of claim 15, wherein the retraction feature is a hypodermic tube.

17. 1. A method of cutting a suture, comprising: a drive wire coupled to a cutter having a central axis, the drive wire being offset from the central axis; providing a the cutter having a first blade defining a first plane and a second blade defining a second plane non-parallel to the first plane, the first blade and the second blade defining an opening; hooking a suture within the opening; severing the suture by pulling the drive wire proximally; A method comprising:

18. 1. A suture cutting system comprising: an endoscope having an insertion tube, the insertion tube having at least one working channel; 1. A cutting device comprising: a handle movably coupled to a flexible drive wire, the handle configured to move the drive wire proximally or distally within the delivery shaft; a cutter coupled to a distal end of the drive wire, wherein movement of the drive wire in a distal direction causes movement of the cutter in a distal direction, the cutter having a transverse longitudinal stiffness length L of less than about 8 mm; a cutting device comprising: A suture cutting system comprising:

19. The suture cutting system of any one of claims 1 to 18, wherein the cutter has a transverse longitudinal stiffness length L of less than about 8 mm.

20. 20. The suture cutting system of any one of claims 1 to 19, wherein the cutter has a transverse longitudinal stiffness length L of greater than about 4 mm.

Images