Distal tip for a medical device

Abstract

The distal tip of the duodenoscope can include a first side surface, a second side surface, a top surface, a bottom surface, and a distal surface. The first side surface, the top surface, and the distal surface can intersect at a first intersection. The first side surface, the bottom surface, and the distal surface can intersect at a second intersection. The second side surface, the bottom surface, and the distal surface can intersect at a third intersection. The second side surface, the top surface, and the distal surface can intersect at a fourth intersection. The first intersection and the fourth intersection can be substantially symmetrical. The second intersection and the third intersection can be substantially symmetrical. The first intersection and the third intersection can be substantially symmetrical. The second intersection and the fourth intersection can be substantially symmetrical.

Description

Cross-reference to related applications

[0001] This application claims priority to U.S. Provisional Application No. 63 / 592,938, filed October 25, 2023, pursuant to 35 USC §119, the entire contents of which are incorporated herein by reference. Technical Field

[0002] Various aspects of this disclosure generally relate to the distal end of a medical device. In particular, among other things, aspects of this disclosure relate to the distal end of a duodenoscope, etc. Background Technology

[0003] A duodenoscopy may include a handle and a sheath, the latter of which can be inserted into the body cavity of the subject. The sheath may terminate at a distal end, which may include features such as optical elements (e.g., a camera, illumination device, etc.), air / water outlets, and a working channel opening. An elevator may be positioned at the distal end and can be actuated to change the orientation of medical devices / instruments passing through the working channel. For example, the elevator may be pivotable or otherwise movable.

[0004] During endoscopic retrograde cholangiopancreatography (ERCP), the operator inserts a duodenoscope into the body cavity and guides its distal end to the surgical site. A potential risk associated with ERCP is the risk of perforation, where the distal end may penetrate the wall of the body cavity (e.g., the esophageal wall or intestinal wall). Such perforation is a serious complication with a high mortality rate. Therefore, there is a need for a distal end of a medical device that reduces the risk of complications. Summary of the Invention

[0005] This disclosure relates to the distal tip of an endoscope that reduces the force required to advance the tip or otherwise has a streamlined profile. Each aspect disclosed herein may include one or more features described in connection with any other disclosed aspect.

[0006] In one example, the distal end of a duodenoscope may include: a first lateral surface; a second lateral surface; a top surface; a bottom surface; and a distal surface. The first lateral surface, top surface, and distal surface intersect at a first junction. The first lateral surface, bottom surface, and distal surface may intersect at a second junction. The second lateral surface, bottom surface, and distal surface may intersect at a third junction. The second lateral surface, top surface, and distal surface may intersect at a fourth junction. The first and fourth junctions may be substantially symmetrical. The second and third junctions may be substantially symmetrical. The second and fourth junctions may be substantially symmetrical.

[0007] Any aspect disclosed herein may, individually or in any combination, include any of the following features. When viewed proximally, the distal surface of the distal end may be substantially symmetrical about at least two planes, said at least two planes comprising lines parallel to or coaxially extending with the central longitudinal axis of the distal end. A portion of the distal surface may be substantially symmetrical about at least four planes, said at least four planes comprising lines parallel to or coaxially extending with the central longitudinal axis of the distal end. The first and second side surfaces may flare outward in a distal direction. Each of the first and second side surfaces may include a proximal portion, a distal portion, and an intermediate portion. The intermediate portion may be located inside the distal and proximal portions, closer to the central longitudinal axis. The top surface may define a first opening and a second opening. The first opening may be configured to receive an imaging device, and the second opening may be configured to receive an illumination element. The top surface may include a cover spanning the space between the first and second openings. This cover may be integrally formed with the remainder of the top surface. The top surface may include at least one opening for receiving an imaging device or illumination element, and wherein a first portion of the top surface located distal to the at least one opening tapers downward toward the distal surface. The first portion may be curved in a lateral direction. The at least one opening may be at least one first opening. The top surface also defines a second opening for receiving a lifter, and wherein the side of the first portion closer to the second opening may be higher than the side of the first portion farther from the second opening. At least a portion of the distal end may have a generally circular cross-sectional shape perpendicular to the central longitudinal axis. The top surface may taper downward from the proximal end to the distal end of the top surface. The central portion of the distal surface may extend further in the distal direction than the lateral portions of the distal surface.

[0008] On the other hand, the distal end of a duodenoscopy may include: a first lateral surface; a second lateral surface; a top surface; a bottom surface; and a distal surface. Each of the first and second lateral surfaces may include a proximal portion, a distal portion, and a middle portion. The middle portion may be located medial to the respective distal and proximal portions.

[0009] Any aspect disclosed herein may have any of the following characteristics, alone or in any combination. The bottom surface may include a proximal portion, a distal portion, and a middle portion. The middle portion may be higher than the proximal and distal portions.

[0010] In another aspect, the distal end of the duodenoscope may include: a first lateral surface; a second lateral surface; a top surface; a bottom surface; and a distal surface. The top surface may include at least one opening for receiving an imaging device or an illumination source. A first portion of the top surface located distal to the at least one opening tapers downward toward the distal surface and bends in the lateral direction.

[0011] Any aspect disclosed herein may have any of the following features. The at least one opening may be at least one first opening. The top surface may also define a second opening for receiving the lifter. The side of the first portion closer to the second opening may be higher than the side of the first portion further from the second opening. The distal portion of the second opening may include a recess defined by an rim. The rim may include a apex and two tapering sides. The first of the two tapering sides may be continuous with the edge of the first portion. Attached Figure Description

[0012] The accompanying drawings, which are incorporated in and form part of this specification, illustrate aspects of this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0013] Figure 1A and Figure 1B An exemplary medical device is depicted.

[0014] Figures 2A to 2E Depicting Figure 1A and Figure 1B An exemplary distal end aspect of a medical device.

[0015] Figures 3A to 3D Depicting Figure 1A and Figure 1B Another exemplary aspect of the distal end of a medical device.

[0016] Figures 4A to 4G Depicting Figure 1A and Figure 1B Another exemplary aspect of the distal end of a medical device.

[0017] Figures 5A to 5D Depicting Figure 1A and Figure 1B Another exemplary aspect of the distal end of a medical device.

[0018] Figures 6A to 6D Depicting Figure 1A and Figure 1B Another exemplary aspect of a medical device is the distal end.

[0019] Figures 7A to 7D Depicting Figure 1A and Figure 1B Another exemplary aspect of the distal end of a medical device.

[0020] Figures 8A to 8E Depicting Figure 1A and Figure 1B Another exemplary aspect of the distal end of a medical device. Detailed Implementation

[0021] The distal tip of a medical device, such as a duodenoscope, may pose a risk of penetrating the body cavity wall of a subject. The disclosed distal tip includes features that help reduce this risk of penetration. For example, compared to a conventional distal tip, the disclosed distal tip may have increased surface curvature, increased symmetry, or other features to reduce the force required to insert and advance the distal tip and / or prevent damage to tissues. For example, the disclosed distal tip may be without sharp edges or may have a softer shape. Furthermore, the disclosed distal tip may reduce areas where pathogens (e.g., bacteria) can easily accumulate. The disclosed distal tip may also include more space to accommodate components of the distal tip (e.g., electronics, such as imaging devices and / or illumination elements). The disclosed distal tip can guide the endoscope. The disclosed distal tip may also increase the range of motion of the distal tip's lifter.

[0022] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and do not limit the claimed invention. As used herein, the terms “comprising,” “including,” “containing,” “having,” “possessing,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements may include not only those elements but also other elements not expressly listed or inherent to such process, method, article, or apparatus. The term “diameter” may refer to the width of a non-circular element. The term “far side” refers to the direction away from the operator, and the term “proximal side” refers to the direction towards the operator. In some figures, arrows labeled “P” and “D” indicate the proximal and far side directions, respectively. The term “exemplary” is used in the sense of “example” rather than “ideal.” The term “approximately” or similar terms (e.g., “substantially”) include values ​​within a range of + / -10% of the stated value.

[0023] Figure 1A An exemplary medical device 10 having a handle 12 and an insertion portion 14 is depicted. Figure 1B The proximal end of the handle 12 is shown. The medical device 10 may also include an umbilical cord 16 for connecting the medical device 10 to a source such as air, water, suction, power, etc., and to an image processing and / or observation device. Although this disclosure specifically refers to duodenoscopy and endoscopy (and combined devices performing duodenoscopy and endoscopy functions), it also covers other types of devices such as bronchoscopes, gastroscopes, endoscopic ultrasound (“EUS”) endoscopes, colonoscopes, ureteroscopes, laparoscopes, cystoscopes, aspiration endoscopes, sheaths, catheters, or similar devices. References to duodenoscopy herein should be understood to cover any of the aforementioned medical devices.

[0024] The insertion portion 14 may include a sheath or shaft 18 and a distal end 20. The distal end 20 may include an imaging device 22 (e.g., a camera) and an illumination element 24 (e.g., a light-emitting diode (LED) or optical fiber). Although the term "illumination element" is used herein, it should be understood that the term "illumination element" may include multiple illumination elements (e.g., multiple LEDs or optical fibers). The distal end 20 may be side-viewed. That is, the imaging device 22 and the illumination element 24 may be radially outward, perpendicular, substantially perpendicular, or otherwise transverse to the longitudinal axis of the shaft 18 and the distal end 20. However, this disclosure is not limited to this arrangement.

[0025] The distal end 20 may also include a lifter 26 for changing the orientation of an accessory or tool inserted into the working channel of the medical device 10. The lifter 26 may also be referred to as a swing frame, pivot frame, lifting base, or any other suitable term. The lifter 26 may be pivotable via, for example, an actuation wire or other control element extending from the handle 12 through the shaft 18 to the lifter 26.

[0026] The distal portion of the shaft 18 connected to the distal end 20 may have a steerable section 28. The steerable section 28 may be, for example, a hinged joint. The shaft 18 and the steerable section 28 may include various structures known in the art or that may become known.

[0027] Handle 12 may have one or more actuator / control mechanisms 30. One or more control mechanisms 30 may provide control over the steerable segment 28. One or more control mechanisms 30 may allow the supply of air, water, suction, etc. For example, handle 12 may include control knobs 32, 34 for left, right, up, and / or down control of the steerable segment 28. For example, one of knobs 32, 34 may provide left / right control of the steerable segment 28, while another of knobs 32, 34 may provide up / down control of the steerable segment 28. Handle 12 may also include one or more locking mechanisms 36a, 36b (e.g., knobs or levers) for preventing steering and / or braking of the steerable segment 28 in at least one of the up, down, left, or right directions. Handle 12 may include a lifter control lever 38 (see...). Figure 1B The lifter control lever 38 can raise and / or lower the lifter 26 via a connection between the lever 38 and an actuation wire extending from the lever 38 through the shaft 18 to the lifter 26. Port 40 allows tools to pass through the port 40 into the working channel of the medical device 10, through the shaft 18, and to reach the distal end 20.

[0028] In use, the operator can insert at least a portion of the shaft 18 into the subject's body cavity. The distal end 20 can be guided to the surgical site within the body cavity. For example, the operator can push the distal end 20 distally to advance it through the body cavity. The operator can insert an accessory (not shown) into port 40 and allow the accessory to pass through the working channel via the shaft 18 to reach the distal end 20. The accessory can exit the working channel at the distal end 20. The user can use the lift control lever 38 to raise the lift 26 and adjust the angle of the accessory to face a desired location (e.g., the papilla of the pancreaticobiliary duct). The user can use the accessory to perform medical procedures.

[0029] Figures 2A to 2E A first exemplary distal end 100 is depicted, which can be used in conjunction with the medical device 10 in place of the distal end 20. The distal end 100 may have any of the features of the distal end 20. The distal end 100 may include a core 102 and a cap 110. During assembly of the distal end 100, the core 102 may be inserted into the cap 110. Elements such as imaging device 22 and illumination element 24 may be mounted or otherwise attached to the core 102, which are shown as being mounted with potting material 140. The distal end 100 may also include a lifter 104, which has any of the features of the lifter 26. The lifter 104 may be rotatable / pivotable relative to other parts of the distal end 100 to raise and / or lower an accessory or tool passing through the working channel of the shaft 18. Further details of the distal end 100 accommodating the lifter 104 will be described below. In an alternative, core 102 can be omitted, or core 102 and cap 110 can be a single integral structure.

[0030] The cap body 110 at the distal end 100 may extend between the proximal end 112 and the distal end 114. A distal surface 120 may be disposed at the distal end 114. The cap body 110 may have a first side surface 116 and a second side surface 118. The first side surface 116 may be located on the side of the cap body 110 opposite to the second side surface 118. The first side surface 116 and the second side surface 118 may be lateral side surfaces of the cap body 110.

[0031] The cap body 110 may have a top surface 122 and a bottom surface 124. The top surface 122 may be located on the side of the cap body 110 opposite to the bottom surface 124. The top surface 122 of the cap body 110 may be located on a side / portion of the cap body 110 that includes a surface or opening for receiving electronic devices (e.g., imaging device 22 and illumination element 24). At least a portion of the top surface 122 adjacent to the second side surface 118 may taper downward (towards the bottom surface 124), as... Figure 2CAs shown. The top surface 122 may also include an opening 148 for receiving the lifter 104. When the lifter 104 rotates / pivots, the range of motion of the accessory or tool (not shown) can pass through various portions of the opening 148.

[0032] The distal end 114 may include a recess 150 communicating with the opening 148. When the lifter 104 is in a lowered configuration (as shown), an accessory extending along the lifter 104 may extend through (and optionally contact) the recess 150. Specifically, as Figure 2A As shown, the recess 150 may have a rounded, smooth surface (rounded / smooth edge). Although the proximal portion 152 of the cap 110 is shown without a protrusion for interacting with the lifter 104 when the lifter 104 is in the raised configuration, this disclosure is not limited thereto. For example, it should be understood that the proximal portion 152 ( Figure 2A and Figure 2E Another portion of the distal end 100 (e.g., core 102) may include this feature for locking or otherwise interacting with the lifter 104.

[0033] Typically, the intersections between the distal surface 120, the first lateral surface 116, the second lateral surface 118, the top surface 122, and the bottom surface 124 can be rounded, without forming sharp angles at the junctions between the surfaces. This rounded junction can provide a smoother interaction between the distal tip 100 and the surface of the subject's body cavity. The distal tip 100 can also have a streamlined shape, such that advancing the distal tip 100 (e.g., distally) requires relatively less force compared to advancing a conventional distal tip.

[0034] The first side surface 116, the top surface 122, and the distal surface 120 may intersect at the first junction 130. The first side surface 116, the bottom surface 124, and the distal surface 120 may intersect at the second junction 132. The second side surface 118, the bottom surface 124, and the distal surface 120 may intersect at the third junction 134. The second side surface 118, the top surface 122, and the distal surface 120 may intersect at the fourth junction 136.

[0035] The intersections 130, 132, 134, and 136 are roughly symmetrical, as shown below. Figure 2D As shown. The symmetry discussed below is based on the assumption that opening 148 / recess 150 does not exist. For example, apart from the junctions 130, 132, 134, 136 and recess 150 / opening 148, the distal surface 120 may be approximately symmetrical about plane D, which is parallel to the central longitudinal axis X of the distal end 100 and / or the cap body 110 (in Figure 2B and Figure 2C(marked) or extends coaxially with the central longitudinal axis X, and extends between the top surface 122 and the bottom surface 124. The distal surface 120 may be about the plane E ( Figure 2D The plane E is approximately symmetrical, extending parallel to or coaxial with the central longitudinal axis X of the distal end 100 and / or the cap body 110, and extending between the first side surface 116 and the second side surface 118. The distal surface 120 may be about the plane F ( Figure 2D The plane F is generally symmetrical, extending parallel to or coaxial with the central longitudinal axis X of the distal end 100 and / or the cap body 110, and extending between the first junction 130 and the third junction 134. The distal surface 120 may be about the plane G ( Figure 2D The plane G is generally symmetrical, extending parallel to or coaxial with the central longitudinal axis X of the distal end 100 and / or the cap body 110, and extending between the second junction 132 and the fourth junction 136. Therefore, a portion of the distal surface 120 may be symmetrical about six planes or at least four planes.

[0036] In other words, the junctions 130, 132, 134, and 136 can have similar or identical shapes, but can rotate about the central longitudinal axis X of the cap body 110. The junctions 130, 132, 134, and 136 can all be rounded to form a smooth, rounded interface between the relevant surfaces. The distal end 114 / distal surface 120 can be a blunt, rounded end that can transition via the junctions 130, 132, 134, and 136 to the side surfaces 116, 118, the top surface 122, and the bottom surface 124. Specifically, as... Figure 2D As shown, when viewing the distal end 114 from the proximal direction, the distal end 114 can have a generally circular shape, which corresponds to the cross-sectional shape of the distal end 114 perpendicular to the central longitudinal axis X. Similarly, as Figure 2C As shown, when viewing the distal end 100 from the side and observing the side surface 118, the distal end 114 can have a generally semi-circular circular shape (excluding the opening 148 / recess 150). When viewing the distal surface 120 from above ( Figure 2B The central portion of the distal surface 120 may extend further distally than the lateral portions of the distal surface 120. In other words, the lateral portions of the distal surface 120 may be located proximal to the central portion of the distal surface 120. Overall, the distal end 114 may have a shape similar to (i.e., approximately) a hemisphere.

[0037] Especially Figure 2BAs shown, the first side surface 116 and the second side surface 118 can flare laterally outward in the distal direction. In other words, the distance between the first side surface 116 and the second side surface 118 can be smaller at the proximal portions of the side surfaces 116 and 118 than at the distal portions. Figure 2B As shown, lines A and B drawn along surfaces 116 and 118, respectively, can diverge from each other in the distal direction / at an angle laterally outward. This shape of the side surfaces 116 and 118 allows for improved guidance of the distal end 100. As the distal end 100 moves through the body cavity, the distal ends 116a and 118a of the side surfaces 116 and 118 can contact the body cavity walls, respectively. More contact can occur at the distal surface 120 and the junctions 130, 132, 134, and 136 compared to the proximal portions of the side surfaces 116 and 118. In some examples, the proximal portions of the side surfaces 116 and 118 may not contact the body cavity walls. Because the more proximal portions of the distal end 100 (proximal to the distal ends 116a and 116a) can be relatively narrower, the portions of the distal end 100 located proximal to the distal ends 116a and 118a can easily move through the body cavity.

[0038] Figures 3A to 3D An alternative distal terminal 200 is depicted, which, unless otherwise stated herein, possesses all the characteristics of the distal terminal 100. For clarity, the differences between the distal terminal 200 and the distal terminal 100 may be highlighted herein, while similarities may be omitted. The distal terminal 200 may be used in place of the distal terminal 20 in conjunction with the medical device 10.

[0039] The distal end 200 may include a core 202 and a cap 210. During assembly of the distal end 200, the core 202 may be inserted into the cap 210. Elements such as imaging device 22 and illumination element 24 may be mounted or otherwise attached to the core 202. The distal end 200 may also include a lifter (not shown) having any of the characteristics of lifters 26, 104.

[0040] The cap body 210 of the distal end 200 may extend between the proximal end 212 and the distal end 214. A distal surface 220 may be disposed at the distal end 214. The cap body 210 may have a first side surface 216 and a second side surface 218. The first side surface 216 may be located on the side of the cap body 210 opposite to the second side surface 218. The first side surface 216 and the second side surface 218 may be lateral side surfaces of the cap body 210. The cap body 210 may have a top surface 222 and a bottom surface 224. The top surface 222 may be located on the side of the cap body 210 opposite to the bottom surface 224. The top surface 222 of the cap body 210 may be a side of the cap body 210 that includes a surface or opening for receiving electronic devices (e.g., imaging device 22 and illumination element 24).

[0041] The top surface 222 may include an opening 248 for receiving a lifter, similar to the opening 148 described above. The distal surface 220 may include a recess 250. Figure 3A (Similar to recess 150). Compared to recess 150, recess 250 can be less inclined in the proximal / distal direction and can be more along... Figure 3A The recess 150 extends in an upward / downward direction. The shape of the recess 150 may be due to the distal surface 220 having a flatter shape than the distal surface 120 and / or due to the top surface 222 extending more horizontally than the top surface 122, as described in further detail below. The proximal portion 252 of the top surface 222 may include a boss 225 for interacting with the lifter, and in some examples, for locking the lifter.

[0042] Typically, the intersections between the distal surface 220, the first side surface 216, the second side surface 218, the top surface 222, and the bottom surface 224 can be rounded, without forming sharp angles at the junctions between the surfaces. This rounded junction provides a smoother interaction between the distal tip 200 and the surface of the subject's body cavity. The distal tip 200 can also have a streamlined shape, such that advancing the distal tip 200 (e.g., distally) requires relatively less force compared to advancing a conventional distal tip.

[0043] The first side surface 216, top surface 222, and distal surface 220 may intersect at a junction 230. The first side surface 216, bottom surface 224, and distal surface 220 may intersect at a junction 232. The second side surface 218, bottom surface 224, and distal surface 220 may intersect at a junction 234. The second side surface 218, top surface 222, and distal surface 220 may intersect at a junction 236. The junctions 230, 232, 234, and 236 may be circular, such that when viewing the distal end 214 from the proximal side (e.g., ... Figure 3AAs shown), the distal end 214 can have a rounded square shape. When viewed from the proximal side, the side surfaces 216, 218 can be approximately straight in the upward / downward direction. When viewed from the proximal side, the bottom surface 224 can be a convex shape with a large radius of curvature (i.e., gently curved). When viewed from the proximal side, the portion 221 of the top surface 222 located near the opening 248 (discussed below) can similarly be a convex shape with a large radius of curvature (i.e., gently curved).

[0044] Similar to the distal end 100, the symmetry discussed below is based on the assumption that the opening 248 / recess 250 does not exist. For clarity, Figures 3A to 3D The lines showing the axis / plane of the distal end 200 are omitted, but they can be similar to... Figures 2A to 2E The lines depicted and discussed above. The distal end 214 may be symmetrical about a plane (similar to plane E) that extends along the central longitudinal axis of the distal end 200 (similar to the central longitudinal axis X of the distal end 100) and extends from the first side surface 216 to the second side surface 218. The distal end 214 may also be symmetrical about a plane (similar to plane D) that extends along the central longitudinal axis of the distal end 200 and extends from the top surface 222 to the bottom surface 224. In other words, the distal end 214 may be symmetrical about a plane extending through the central longitudinal axis of the cap body 210 and... Figure 3A The plane extending vertically is symmetrical, and also about the central longitudinal axis extending through the cap body 210 and in Figure 3A The planes extending left and right are symmetrical. The intersections 230, 232, 234, and 236 can be symmetrical to each other. In other words, the intersections 230, 232, 234, and 236 can be approximately symmetrical, such as... Figure 3D As shown. In other words, the junctions 230, 232, 234, and 236 may have similar or identical shapes, but may rotate around the central longitudinal axis of the cap body 210.

[0045] like Figure 3C As shown, the distal surface 220 may have a flat portion 220a. The flat portion 220a may extend substantially perpendicular to the central longitudinal axis of the cap body 210. Confluences 230, 232, 234, and 236 may form a curved transition between the flat portion 220a, the top surface 222, and the bottom surface 224. The radii of curvature of the confluences 230, 232, 234, and 236 may be large to facilitate better sliding / gliding through the subject's body cavity.

[0046] Compared to junctions 130, 132, 134, and 136, junctions 230, 232, 234, and 236 may curve downwards / upwards less gently to the distal surface 220. In other words, the radius of curvature of the transition between the top surface 222 and the distal surface 220, and between the bottom surface 224 and the distal surface 220, may be smaller than the radius of curvature of the corresponding element at the distal end 100. The shape of junctions 230, 232, 234, and 236 may contribute to the distal surface 220 having a flat portion 220a.

[0047] The distal end 200 may include a cover 240 extending over a recess for mounting the imaging device 22 and the illumination element 24. The cover 240 may have openings 241a, 241b formed therein. The cover 240 may extend between the openings 241a, 241b to cover the space between them. The imaging device 22 and the illumination element 24 may be mounted within the distal end 200 such that the imaging device 22 is aligned with opening 241a and the illumination element 24 is aligned with opening 241b, and vice versa. Although the cover 240 is shown as having two openings 241a, 241b, it should be understood that the cover 240 may include any suitable number of openings corresponding to the number of electronic devices enclosed / shielded / covered by the cover 240. The cover 240 may be integrally formed as a single piece of material with the cap body 210 (including the remainder of the top surface 222). Alternatively, the cover 240 may be a separate piece of material. The cover 240 may help reduce the presence of sharp edges associated with the imaging device 22 and the illumination element 24. The cover 240 may be recessed relative to the surrounding portion of the top surface 222. A smooth transition may exist between the cover 240 and the top surface 222 to avoid a hard edge between them. The portion 223 of the top surface 222 located distal to the cover 240 may be curved to form a smooth transition with the distal surface 220.

[0048] Comparing distal end 100 and distal end 200, the top surface 122 of distal end 100 may taper downwards as described above, and the top surface 122 may be generally horizontal (generally parallel to the central longitudinal axis of distal end 200). When viewed proximally, the distal surface 120 of distal end 100 may have a generally circular shape, while the distal surface 220 may have a rounded square shape. Although side surfaces 116, 118 may flare outwards, side surfaces 216, 218 may be generally parallel to each other and / or parallel to the central longitudinal axis of distal end 200. Distal end 100 may not have a structure similar to cap 240. The above differences are not exclusive, and other differences exist between distal ends 100 and 200. Furthermore, it should be understood that the features of distal end 100 can be combined with the features of distal end 200 in any suitable arrangement. For example, distal end 200 may have flared side surfaces 216, 218. The distal end 100 may include a cap similar to the cap 240.

[0049] Figures 4A to 4G An alternative distal terminal 300 is depicted, which, unless otherwise stated herein, possesses any of the characteristics of distal terminals 100 and 200. For clarity, the differences between distal terminal 300 and distal terminals 100 and 200 may be highlighted herein, while similarities may be omitted. In particular, distal terminal 300 may resemble distal terminal 200. Distal terminal 300 may be used in place of distal terminal 20 in conjunction with medical device 10.

[0050] The distal end 300 may include a core 302 and a cap 310. During assembly of the distal end 300, the core 302 may be inserted into the cap 310. Elements such as imaging device 22 and illumination element 24 may be mounted or otherwise attached to the core 302. The distal end 300 may also include a lifter (not shown) having any of the characteristics of lifters 26, 104.

[0051] The cap body 310 at the distal end 300 may extend between the proximal end 312 and the distal end 314. A distal surface 320 may be disposed at the distal end 314. The cap body 310 may have a first side surface 316 and a second side surface 318. The first side surface 316 may be located on the side of the cap body 310 opposite to the second side surface 318. The first side surface 316 and the second side surface 318 may be lateral side surfaces of the cap body 310. The cap body 310 may have a top surface 322 and a bottom surface 324. The top surface 322 may be located on the side of the cap body 310 opposite to the bottom surface 324. The top surface 322 of the cap body 310 may be a side of the cap body 310 that includes a surface or opening for receiving electronic devices (e.g., imaging device 22 and illumination element 24).

[0052] Typically, the intersections between the distal surface 320, the first side surface 216, the second side surface 318, the top surface 322, and the bottom surface 324 can be rounded, without forming sharp angles at the junctions between the surfaces. This rounded junction can help provide a smoother interaction between the distal tip 300 and the surface of the subject's body cavity. The distal tip 300 can also have a streamlined shape, such that advancing the distal tip 300 (e.g., distally) requires relatively less force compared to advancing a conventional distal tip.

[0053] The first side surface 316, top surface 322, and distal surface 320 may intersect at the junction 330. The first side surface 316, bottom surface 324, and distal surface 320 may intersect at the junction 332. The second side surface 318, bottom surface 324, and distal surface 320 may intersect at the junction 334. The second side surface 318, top surface 322, and distal surface 320 may intersect at the junction 336.

[0054] Similar to top surface 222, top surface 322 may include a cap 340, which has any of the characteristics of cap 240. A portion 323 of top surface 322 located distal to cap 340 and / or cap 340 itself may be fused to or at least partially integrated with other surfaces of cap body 310. Although the shape of portion 323 is discussed below, it should be understood that the same features may be applied alternatively to cap 340. Special Reference Figure 4A and Figure 4G Part 323 may taper downwards (towards the bottom surface 324) in the direction toward the first side surface 316. In other words, part 323 may taper downwards in a laterally outward direction. The tapering shape may be curved (e.g., wavy) to provide a smooth blend between the top surface 322 and the first side surface 316. In some examples, the entire cover 340 may taper downwards in a laterally outward direction (towards the first side surface 316). Figure 4A and Figure 4G As shown, the proximal portion of the cover 340 may be higher than the distal portion and / or portion 323 of the cover 340 (farther from the bottom surface 324).

[0055] Compare distal end 200 with distal end 300, with particular reference. Figure 3A , Figure 3C , Figure 4A and Figure 4D .like Figure 3C As shown (viewed from the side at the distal end 200, facing the second surface 218), portion 223 of the top surface 222 and / or the junction 230 may extend slightly distally beyond the adjacent portion of the side junction 236 and the top surface 222. Portion 233 may protrude slightly. In contrast, as... Figure 4DAs shown (viewed from the side, distal end 300, facing the second side surface 318), portion 323 can smoothly merge with the junction 330 and may not protrude so much / extend further distally. Comparison Figure 3A (distal end 200) and Figure 4A (Distal end 300), portion 223 may extend approximately parallel to the central longitudinal axis of distal end 200, while portion 323 may taper downward and merge into the junction 330 / distal surface 320 of distal end 300.

[0056] Figures 5A to 5D An alternative distal terminal 400 is depicted, which, unless otherwise stated herein, possesses any of the characteristics of distal terminals 100, 200, and 300. For clarity, the differences between distal terminal 400 and distal terminals 100, 200, and 300 may be highlighted herein, while similarities may be omitted. Distal terminal 400 may be used in place of distal terminal 20 in conjunction with medical device 10.

[0057] The distal end 400 may include a core 402 and a cap 410. During assembly of the distal end 400, the core 402 may be inserted into the cap 410. Components such as imaging device 22 and illumination element 24 may be mounted or otherwise attached to the core 402. Figures 5A to 5D In this configuration, imaging device 22 and illumination element 24 are shown as installed / encapsulated. The distal end 400 may also include a lifter 404 having any of the characteristics of lifters 26, 104.

[0058] The cap body 410 at the distal end 400 may extend between the proximal end 412 and the distal end 414. A distal surface 420 may be disposed at the distal end 414. The cap body 410 may have a first side surface 416 and a second side surface 418. The first side surface 416 may be located on the side of the cap body 410 opposite to the second side surface 418. The first side surface 416 and the second side surface 418 may be lateral side surfaces of the cap body 410. The cap body 410 may have a top surface 422 and a bottom surface 424. The top surface 422 may be located on the side of the cap body 410 opposite to the bottom surface 424. The top surface 422 of the cap body 410 may be a side of the cap body 410 that includes a surface or opening for receiving electronic devices (e.g., imaging device 22 and illumination element 24).

[0059] Typically, the intersections between the distal surface 420, the first side surface 416, the second side surface 418, the top surface 422, and the bottom surface 424 can be rounded, without forming sharp angles at the junctions between the surfaces. This rounded junction provides a smoother interaction between the distal tip 400 and the surface of the subject's body cavity. The distal tip 400 can also have a streamlined shape, so that advancing the distal tip 400 requires relatively less force compared to advancing a conventional distal tip.

[0060] The first side surface 416, top surface 422, and distal surface 420 may intersect at the junction 430. The first side surface 416, bottom surface 424, and distal surface 420 may intersect at the junction 432. The second side surface 418, bottom surface 424, and distal surface 420 may intersect at the junction 434. The second side surface 418, top surface 422, and distal surface 420 may intersect at the junction 436.

[0061] Unlike distal ends 100, 200, and 300, the distal end 414 of distal end 400 can be asymmetrical. (Reference) Figure 5B (It is illustrated by viewing the distal end 414 in the proximal direction), the first side 422a of the top surface (which may include the imaging device 22 and the illumination element 24, such as...) Figure 5C and Figure 5D The portion 423 of the top surface 422, which includes the opening 448 for the lifter 404, can be recessed in the downward direction relative to the second side 422a of the top surface 422. Specifically, the first side 422a can be further recessed in the downward direction compared to the corresponding structures of the distal ends 100, 200, 300. The portion 423 of the top surface located distal to the imaging device 22 and the illumination element 24 (as shown) Figure 5C and Figure 5D It can taper upwards in the direction toward the first side surface 416 (in the lateral outward direction).

[0062] Still referencing Figure 5B The junctions 430, 432, 434, and 436 can be asymmetrical. The first side surface 416 can flare outwards in the upward direction, such that it is farther from the second side surface 418 near the top surface 422 than near the bottom surface 424. When viewing the distal end 414 from the near side, the second side surface 418 can extend in a generally vertical direction. In contrast, when viewed from the same direction, the first side surface 416 can tilt outwards in the upward direction. Figure 5B In the view, the angle at which the junction 436 falls to the lower left can be steeper than the angle at which the junction 430 falls to the lower right.

[0063] like Figure 5AAs shown, specifically (side view facing the second side surface 418), the top surface 422 can taper downwards gradually in the distal direction. The taper of the top surface 422 can be approximately uniform, such that the intersection between the top surface 422 and the second side surface 418 forms an approximately straight line. The bottom surface 424 can taper upwards gradually. The distal portion 424a of the bottom surface 424 can curve upwards at a greater rate of change than the proximal portion of the bottom surface 424. The upward angle of the distal portion 424a of the bottom surface 424 can have a steeper angle than the downward angle of the top surface 424.

[0064] Refer again Figure 5B The radii of curvature of the junctions 432 and 434 in the lateral (side-to-side) direction can be greater than the radii of curvature of the junctions 430 and 436. In other words, the bottom portion of the distal end 414 / distal surface 420 can be more rounded than the top portion of the distal end 414 / distal surface 420.

[0065] Figures 6A to 6D An alternative distal terminal 500 is depicted, which, unless otherwise stated herein, possesses any of the characteristics of distal terminals 100, 200, 300, and 400. For clarity, the differences between distal terminal 500 and distal terminals 100, 200, 300, and 400 may be highlighted herein, while similarities may be omitted. Distal terminal 500 may be used in place of distal terminal 20 in conjunction with medical device 10.

[0066] The distal end 500 may include a core 502 and a cap 510. During assembly of the distal end 500, the core 502 may be inserted into the cap 510. Elements such as imaging device 22 and illumination element 24 may be mounted or otherwise attached to the core 502. The distal end 500 may also include a lifter 504, which has any of the characteristics of lifters 26, 104, 404.

[0067] The cap body 510 at the distal end 500 may extend between the proximal end 512 and the distal end 514. A distal surface 520 may be disposed at the distal end 514. The cap body 510 may have a first side surface 516 and a second side surface 518. The first side surface 516 may be located on the side of the cap body 510 opposite to the second side surface 518. The first side surface 516 and the second side surface 518 may be lateral side surfaces of the cap body 510. The cap body 510 may have a top surface 522 and a bottom surface 524. The top surface 522 may be located on the side of the cap body 510 opposite to the bottom surface 524. The top surface 522 of the cap body 510 may be a side of the cap body 510 that includes a surface or opening for receiving electronic devices (e.g., imaging device 22 and illumination element 24).

[0068] Typically, the intersections between the distal surface 520, the first side surface 516, the second side surface 518, the top surface 522, and the bottom surface 524 can be rounded, without forming sharp corners at the junctions between the surfaces. This rounded junction can help provide a smoother interaction between the distal tip 500 and the surface of the subject's body cavity. The distal tip 500 can also have a streamlined shape, such that advancing the distal tip 500 (e.g., distally) requires relatively less force compared to advancing a conventional distal tip.

[0069] The first side surface 516, top surface 522, and distal surface 520 may intersect at the first junction 530. The first side surface 516, bottom surface 524, and distal surface 520 may intersect at the second junction 532. The second side surface 518, bottom surface 524, and distal surface 520 may intersect at the third junction 534. The second side surface 518, top surface 522, and distal surface 520 may intersect at the fourth junction 536.

[0070] When viewing the distal end 514 from the proximal direction, the junctions 530, 532, 534, and 536 can have shapes similar to those of the junctions 130, 132, 134, and 136, such as... Figure 6B As shown. The distal end 514 / distal surface 520 of the distal end 500 can have any of the characteristics of the distal end 114 / distal surface 120. For example, as Figure 6B As shown, when viewed in the proximal direction, the distal end 514 can have a generally circular shape overall. However, similar to the distal end 400, the first portion 522a of the top surface 522 (having the imaging device 22 and the illumination element 24) can be recessed relative to the second portion 522b of the top surface 522, which has an opening 548 for receiving the lifter 504. Although the distal surface 120 of the distal end 100 can be symmetrical about various axes (as described above) and has a generally circular shape when viewed in the proximal direction ( Figure 2D However, the proximal portions of the lateral surfaces 516 and 518 can contribute to the distal end 500 when viewed in the proximal direction ( Figure 6B It has a generally circular shape. For example, the proximal portion 511 of the cap body 510 may have a generally circular shape in a cross-section perpendicular to the central longitudinal axis of the distal end 500.

[0071] like Figure 6A and Figure 6CAs shown, the bottom surface 524 and the side surfaces 516, 518 may have a profile that tapers inward and then outward in the distal direction. The bottom surface 524 may taper upward (towards the top surface 522) as it moves distally from the proximal portion 525a to the middle portion 525b. From the middle portion 525b to the distal portion 525c, the bottom surface 524 may taper downward as it moves distally. In other words, the proximal portion 525a and the distal portion 525c may be located below the middle portion 525b. The side surfaces 516, 518 may taper towards each other (laterally inward) from the proximal portions 517a, 519a to the middle portions 517b, 519b, respectively, as they move distally. When the side surfaces 516 and 518 move in the distal direction, they gradually taper outward (laterally outward) from the middle portions 517b and 519b toward the distal portions 517c and 519c, respectively.

[0072] Therefore, similar to the distal end 100, the distal end 500 is wider at the distal portions 517c, 519c, 525c than at the intermediate portions 517b, 519b, 525b, which can facilitate easier movement of the distal end 500 through the body cavity. In at least some cases, the intermediate portions 517b, 519b, 525b may not contact the body cavity wall, thereby reducing the amount of contact between the distal end 500 and the body cavity wall and facilitating easier advancement of the distal end 500. The proximal portions 517a, 519a, 525a may contact the body cavity wall. The contact of the proximal portions 517a, 519a, 525a can help prevent the intermediate portions 517b, 519b, 525b from contacting the body cavity wall.

[0073] like Figure 6A and Figure 6D As shown, when viewed from the side, the junctions 530, 532, 534, and 536 can be curved. The transitions between the top surface 522 and the distal surface 520, and between the bottom surface 524 and the distal surface 520, can have curves with a large radius of curvature, providing a gradual and smooth transition between the surfaces without sharp edges that could easily pierce the tissue.

[0074] In addition to what is described herein, top surface 522 may have any of the characteristics of top surface 422. Compared to other distal ends disclosed herein, top surface 522 may include a larger first portion 522a for receiving imaging device 22 and illumination element 24. Therefore, top surface 522 may allow for the use of a larger imaging device 22 and / or illumination element 24, which may help improve the performance of medical device 10.

[0075] Figures 7A to 7DAn alternative distal terminal 600 is depicted, which, unless otherwise stated herein, possesses any features of distal terminals 100, 200, 300, 400, and 500. For clarity, the differences between distal terminal 600 and distal terminals 100, 200, 300, 400, and 500 may be highlighted herein, while similarities may be omitted. In particular, distal terminal 600 may specifically share features of distal terminals 200 and 300. Distal terminal 600 may be used in place of distal terminal 20 in conjunction with medical device 10.

[0076] The distal end 600 may include a core 602 and a cap 610. During assembly of the distal end 600, the core 602 may be inserted into the cap 610. Elements such as imaging device 22 and illumination element 24 may be mounted or otherwise attached to the core 602. The distal end 600 may also include a lifter (not shown) having any of the characteristics of lifters 26, 104, 404.

[0077] The cap body 610 at the distal end 600 may extend between the proximal end 612 and the distal end 614. A distal surface 620 may be disposed at the distal end 614. The cap body 610 may have a first side surface 616 and a second side surface 618. The first side surface 616 may be located on the side of the cap body 610 opposite to the second side surface 618. The first side surface 616 and the second side surface 618 may be lateral side surfaces of the cap body 610. The cap body 610 may have a top surface 622 and a bottom surface 624. The top surface 622 may be located on the side of the cap body 610 opposite to the bottom surface 624. The top surface 622 of the cap body 610 may be a side of the cap body 610 that includes a surface or opening (not shown but having any suitable shape or size) for receiving electronic devices (e.g., imaging device 22 and illumination element 24).

[0078] Typically, the intersections between the distal surface 620, the first side surface 616, the second side surface 618, the top surface 622, and the bottom surface 624 can be rounded, without forming sharp angles at the junctions between the surfaces. This rounded junction can help provide a smoother interaction between the distal tip 600 and the surface of the subject's body cavity. The distal tip 600 can also have a streamlined shape, such that advancing the distal tip 600 (e.g., distally) requires relatively less force compared to advancing a conventional distal tip.

[0079] The first side surface 616, top surface 622, and distal surface 620 may intersect at the first junction 630. The first side surface 616, bottom surface 624, and distal surface 620 may intersect at the second junction 632. The second side surface 618, bottom surface 624, and distal surface 620 may intersect at the third junction 634. The second side surface 618, top surface 622, and distal surface 620 may intersect at the fourth junction 636.

[0080] When looking at the near side ( Figure 7B The overall shape of the distal end 600 may be similar to that of the distal ends 200 and / or 300 described above. Like the distal end 300, the first portion 622a (closer to the first side surface 616) of the top surface 622 of the distal end 600 may include a distal portion 623, which may be integrated with the other surfaces of the cap 310 and / or have any of the features of the portion 323 described above. Unlike the distal end 300, the distal end 600 may not have a cap similar to the cap 340. Alternatively, the distal end 600 may include such a cap. Although the first portion 622a is shown as not being used to receive electronic devices (e.g., imaging device 22 and illumination element 24, in...) Figure 7C and Figure 7D The opening (marked in the middle) may include, but it should be understood, the first part 622a may include such an opening (e.g., as shown for the distal ends 400, 500).

[0081] The second portion 622b of the top surface 622 (closer to the second side surface 618) may include an opening 648 for receiving a lifter. The second portion 622b may include a distal portion 625, which may be adjacent to the second side surface 618 and the distal surface 620. Although the distal portion 625 is described as part of the top surface 622, the distal portion 625 may alternatively be considered as part of the fourth junction 636. The distal portion 625 may taper downward toward the bottom surface 624. Therefore, the lateral profile of the second side surface 618 / fourth junction 636 ( Figure 7A ) can be similar to the lateral profile of the second lateral surface 118 of the distal end 100 ( Figure 2C The distal portion of the second side surface 618 may be approximately symmetrical about a line extending longitudinally along the second side surface 618, midway between the top surface 622 and the bottom surface 624.

[0082] Figures 8A to 8EAn alternative distal terminal 700 is depicted, which, unless otherwise stated herein, possesses any features of distal terminals 100, 200, 300, 400, 500, and 600. For clarity, the differences between distal terminal 600 and distal terminals 100, 200, 300, 400, 500, and 600 may be highlighted herein, while similarities may be omitted. In particular, distal terminal 600 may specifically share features of distal terminals 300 and 400. Distal terminal 700 may be used in place of distal terminal 20 in conjunction with medical device 10.

[0083] The distal end 700 may include a core 702 and a cap 710. During assembly of the distal end 700, the core 702 may be inserted into the cap 710. Elements such as imaging device 22 and illumination element 24 may be mounted or otherwise attached to the core 702. The distal end 700 may also include a lifter (not shown) having any of the characteristics of lifters 26, 104, 404.

[0084] The cap body 710 at the distal end 700 may extend between the proximal end 712 and the distal end 714. A distal surface 720 may be located at the distal end 714. The cap body 710 may have a first side surface 716 and a second side surface 718. The first side surface 716 may be located on the side of the cap body 710 opposite to the second side surface 718. The first side surface 716 and the second side surface 718 may be lateral side surfaces of the cap body 710. The cap body 710 may have a top surface 722 and a bottom surface 724. The top surface 722 may be located on the side of the cap body 710 opposite to the bottom surface 724. The top surface 722 of the cap body 710 may be a side of the cap body 710 that includes a surface or opening (not shown but having any suitable shape or size) for accommodating electronic devices (e.g., imaging device 22 and illumination element 24).

[0085] Typically, the intersections between the distal surface 720, the first side surface 716, the second side surface 718, the top surface 722, and the bottom surface 724 can be rounded, without forming sharp angles at the junctions between the surfaces. This rounded junction helps to smooth the interaction between the distal tip 700 and the surface of the subject's body cavity. The distal tip 700 can also have a streamlined shape, so that advancing the distal tip 700 (e.g., distally) requires relatively less force compared to advancing a conventional distal tip.

[0086] The first side surface 716, top surface 722, and distal surface 720 may intersect at the first junction 730. The first side surface 716, bottom surface 724, and distal surface 720 may intersect at the second junction 732. The second side surface 718, bottom surface 724, and distal surface 720 may intersect at the third junction 734. The second side surface 718, top surface 722, and distal surface 720 may intersect at the fourth junction 736.

[0087] When viewed from the proximal direction ( Figure 8B The overall external shape / perimeter of the distal end 700 can be similar to that of the distal end 400 described above. The side surfaces 716 and 718 can extend substantially vertically. The bottom surface 724 can slope slightly upwards as it moves from the first side surface 716 to the second side surface 718. Therefore, the second junction 732 can be higher than the third junction 734.

[0088] The first portion 722a of the top surface 722 of the distal end 700, closer to the first side surface 716, may include a distal portion 723, which may be integrated with the other surfaces of the cap body 710 and have any of the features of the portion 323 described above.

[0089] The second portion 722b of the top surface 722 (closer to the second side surface 718) may include an opening 748 for receiving the lifter. Specifically, as Figure 8B As shown, the second portion 722b may include a distal edge 725. The distal edge 725 may define a recess 750, wherein the distal edge 725 is the edge of the recess 750, which may communicate with the opening 748 and receive an accessory device when the lifter is in a lowered configuration. The distal edge 725 of the top surface 722 may be disposed around the opening 748 and the recess 750. The recess 750 (e.g., the distal edge 725) may have a tapered first portion 751a and a tapered second portion 751b. Each of the first portion 751a and the second portion 751b may be straight, curved, or a combination of both. The first portion 751a and the second portion 751b may intersect at a lowest point 752, which may be a recess. In some examples, the first portion 751a and the second portion 751b may have the same tapering angle toward the lowest point 752. In other examples, the downward angle of the first portion 751a can be steeper than that of the second portion 751b. In the example, the second portion 751b can be continuous with the distal edge 726 of portion 723 to form a single continuous line / curve. The second portion 751b can be shorter than the first portion 751a because the distal edge 725 can be lower than the side 757 of the first portion 751a opposite to the lowest point 752. The overall shape of the distal end 714 can be smooth and integrated.

[0090] like Figure 8C As shown (viewed from above of the distal end 700), the distal surface 720 may be rounded, such that the middle portion of the distal surface 720 is more distal than the portion of the distal surface 720 that is closer to the lateral surfaces 716, 718. These features of the distal end 714 can be combined to form point contact between the distal end 714 and the tissue, which can help allow the distal end 700 to glide or slide more easily through the body cavity.

[0091] While the principles of this disclosure are described herein with reference to illustrative examples for specific applications, it should be understood that this disclosure is not limited thereto. Those skilled in the art, upon receiving the teachings provided herein, will recognize that additional modifications, applications, and equivalent substitutions fall within the scope of the examples described herein. Furthermore, various elements from each presented example can be combined to achieve the same or similar results as one or more of the disclosed embodiments. Therefore, the features of the examples should not be considered mutually exclusive or applicable to any particular distal end, and can be combined in any suitable manner. Consequently, the invention should not be considered limited to the foregoing description.

Claims

1. A distal end of a duodenoscope, said distal end comprising: First side surface; Second side surface; Top surface; Bottom surface; as well as The distal surface, wherein the first side surface, the top surface and the distal surface intersect at a first junction, wherein the first side surface, the bottom surface and the distal surface intersect at a second junction, wherein the second side surface, the bottom surface and the distal surface intersect at a third junction, and wherein the second side surface, the top surface and the distal surface intersect at a fourth junction; The first junction and the fourth junction are approximately symmetrical, and the second junction and the third junction are approximately symmetrical.

2. The distal end according to claim 1, wherein the first junction and the third junction are substantially symmetrical, and wherein the second junction and the fourth junction are substantially symmetrical.

3. The distal end according to claim 1, wherein, When viewed from the proximal side, the distal surface of the distal end is substantially symmetrical about at least two planes, the at least two planes including lines that extend parallel to or coaxially with the central longitudinal axis of the distal end.

4. The distal end of claim 3, wherein a portion of the distal surface is substantially symmetrical about at least four planes, the at least four planes comprising lines extending parallel to or coaxial with the central longitudinal axis of the distal end.

5. The distal end according to any one of claims 1-4, wherein the first side surface and the second side surface are flared outward in the distal direction.

6. The distal end according to any one of claims 1-4, wherein each of the first side surface and the second side surface includes a proximal portion, a distal portion and an intermediate portion, and wherein the intermediate portion is located inside the distal portion and the proximal portion, closer to the central longitudinal axis.

7. The distal end according to any one of claims 1-6, wherein the top surface defines a first opening and a second opening, wherein the first opening is configured to receive an imaging device, and wherein the second opening is configured to receive an illumination element.

8. The distal end of claim 7, wherein the top surface includes a cover spanning the space between the first opening and the second opening.

9. The distal end of claim 8, wherein the cap is integrally formed with the remainder of the top surface.

10. The distal end of claim 1, wherein the top surface includes at least one opening for receiving an imaging device or an illumination element, and wherein a first portion of the top surface located distal to the at least one opening tapers downward toward the distal surface.

11. The distal end of claim 10, wherein the first portion is bent in the lateral direction.

12. The distal end of claim 11, wherein the at least one opening is at least one first opening, wherein the top surface further defines a second opening for receiving a lifter, and wherein the side of the first portion closer to the second opening is higher than the side of the first portion further away from the second opening.

13. The distal end of claim 1, wherein at least a portion of the distal end has a generally circular cross-sectional shape perpendicular to the central longitudinal axis.

14. The distal end of claim 1, wherein the top surface tapers downward from the proximal end of the top surface to the distal end of the top surface.

15. The distal end of claim 11, wherein the central portion of the distal surface extends further in the distal direction than the lateral portion of the distal surface.

Images