Atraumatic tip for use in a surgical device

Abstract

A distal tip for an endoscope that is to be inserted into a lumen of a human or animal body, the distal tip comprising a proximal mounting portion for the connection of the distal tip to a distal end portion of the endoscope; a distal end of the distal tip to engage soft tissue distal to the endoscope during an advance of the endoscope; and a flexible bending portion arranged between the distal end and the proximal mounting portion and configured to enable a transverse deflection of the distal end with respect to the proximal mounting portion.

Description

Atraumatic tip for use in a surgical deviceFIELD OF THE INVENTION[oooi] The present invention is in the field of medical technology. In particular, the invention relates to a distal tip for use in a surgical device such as an endoscope that is to be inserted into the human or animal body at least in part.BACKGROUND

[0002] An endoscope is a surgical device that may be used to access (e.g., view or remove) or treat tissue within the body of a patient by inserting one or more medical tools into the body through an incision in the body or an orifice of the body. The endoscope may comprise an interface / control portion and an insertion tube that is coupled to the interface / control portion. The insertion tube is configured to be inserted into the body of the patient and may comprise one or more channels to provide access to tissue within the body. The one or more channels may e.g. be configured to receive a medical tool and / or a fluid and to guide the medical tool and fluid, respectively, to the tissue of interest.

[0003] The endoscope may feature a camera for guiding an advance of the endoscope through a surgical or biological anatomy of the body, for viewing and / or treating soft tissue within the body of the patient, in particular as part of performing or monitoring a treatment of the patient, e.g. as part of a minimally invasive surgery.

[0004] The insertion tube may be bendable to facilitate insertion into the patient’s body. For this, the insertion tube may comprise one or more passively and / or actively bendable sections to navigate a biological lumen, such as a substantially tubular biological lumen, e.g. the esophagus, duodenum, jejunum and / or ileum, or such as a cavity deviating from a strictly tubular shape, such as an organ, e.g. the stomach.

[0005] Flexible endoscopes are in most cases inserted into the body via natural orifices. During insertion of the endoscope into the body, the endoscope may be guided along the biological lumen up to the viewing or treatment site, while a user may receive visual feedback from the camera or haptic feedback from collisions with soft tissue to navigate the biological lumen.[ooo6] Endoscopes are generally developed to have rounded edges and to be as atraumatic and flexible as possible, to minimize the likelihood of causing soft tissue damage or perforation, nevertheless the necessary flexibility is often partly counterproductive to the purpose of therapeutic interventions, where stability and stiffness of the endoscope could be useful. Likewise, the smaller the endoscope, the larger the risk of tissue perforation. Duodenoscopes, in particular, have a side facing camera which results in the scope being inserted semi-blindly, as the camera may have no or only a limited view of the distal tip, further increasing the likelihood of inadvertent perforation.US 20150297391 Al discloses medical catheters and, more particularly, delivery catheters for delivering an occluding device to an internal body lumen. The delivery device can e.g. be delivered into the lumen or an anatomical passageway' via use of an endoscope and its tip includes a slanted facial opening for the deployment of the occluding device. The slanted facial opening takes on a generally ovoid configuration for improved tip flexibility.SUMMARY OF THE INVENTION

[0007] To avoid inadvertent tissue damage, polymer caps may shroud a head of the endoscope, such as to smooth features of the endoscope head. The known surgical devices may however still suffer from inadvertent tissue damage during an insertion of the surgical device through the lumen or require highly skilled personnel, in particular when using endoscopes for treating or viewing lateral tissue sections with respect to an extension direction of the endoscope, or when using devices with small diameters. In such devices, visual monitoring and control of the advance of the endoscope head may be limited or prone to error. However, such features, e.g. a side facing camera, may be advantageous in Endoscopic retrograde cholangiopancreatography (ERCP) applications, such as in the context of bile duct and pancreatic duct access, e.g. for observation or surgery.

[0008] It is thus an object to facilitate control of the surgical devices by a user and to minimize inadvertent tissue damage or perforation during endoscope use, e.g. during an advance of the surgical device through the biological lumen, a surgical procedure, or removal of matter from an intervention site.

[0009] According to a first aspect, a distal tip for a surgical device, in particular an endoscope, is provided that is to be inserted into a lumen of a human or animal body. The distal tip comprises a proximal mounting portion for connection of the distal tip to a distal end portionof the surgical device, a distal end of the distal tip to engage soft tissue distal to the endoscope during an advance of the surgical device, and a flexible bending portion arranged between the distal end and the proximal mounting portion. The flexible bending portion is configured to enable a transverse deflection of the distal end with respect to the proximal mounting portion.[ooio] The distal tip maybe a distal tip for an insertion tube of an endoscope. The endoscope may be part of an endoscope system, e.g. a robotic or manual endoscope system. The distal tip can be configured to guide an advance of the surgical device through the lumen, such as through the esophagus and the stomach of a patient, and may be arranged at a distal side of an endoscope head assembly. The distal tip may engage biological tissue, when the distal head assembly is advanced through the lumen, such as to guide the distal head assembly along a natural geometiy of the lumen. The distal end can be arranged at a distal end face of the distal tip and can define a distal contact point for abutment against a varying geometry of the biological lumen. The distal end maybe configured to first engage soft tissue during an advance of the surgical device, e.g. during an advance through the biological lumen and / or while navigating an expanded space of a biological lumen, such as to engage the stomach wall while advancing the endoscope along the gastrointestinal tract. In the case of an abutment of the distal tip against soft tissue section hindering the advance of the distal tip, the distal end may be deflected in a transverse direction about the flexible bending portion for preventing inadvertent tissue damage and / or providing feedback to a user. The transverse deflection may be transverse to the advancement direction of the distal tip and / or transverse to an extension direction of the distal tip along an extension from the proximal mounting portion to the distal end.[oon] The advancement direction may be defined by the surgical device, which may be advanced through the lumen as a tube-shaped device, wherein the advancement direction may follow a main extension direction of the surgical device. At the distal tip, the advancement direction maybe defined by the proximal mounting portion, e.g. perpendicular to a mounting face of the proximal mounting portion. The mounting portion may define an orientation of the distal tip with respect to the distal end portion of the surgical device and may therefore define an advancement direction of the distal tip based on a mounted configuration on the distal end portion of the surgical device.

[0012] The deflection of the distal end transverse to the advancement direction may increase an effective surface area of the distal tip in contact with surrounding soft tissue, may divert an advancement force applied along the advancement direction of the distal head assembly, andmay provide visual and / or haptic feedback to a user. For example, when the surgical device features a camera with an oblique viewing angle with respect to the advancement direction, the transverse deflection of the distal end may induce a transverse shift of the camera view with respect to the surrounding tissue, such as to provide visual feedback of the abutment to the user.

[0013] The length of the distal tip extending from a distal end face the surgical device may be greater than 50% of a maximum lateral extension (e.g. diameter) of the surgical device, greater than the maximum lateral extension of the surgical device, or greater than 1.5 or 2 times the maximum lateral extension of the surgical device, e.g. to promote transverse deflection of the distal end.

[0014] In some examples, the flexible bending portion is integrally formed with the distal end and / or the proximal mounting portion.

[0015] For example, the flexible tip may be an integrally formed polymer part with different portions of the part defining the distal end, the flexible bending portion and the proximal mounting portion.

[0016] In some examples, the flexible bending portion has a hardness of 20-90, in particular 20-80, preferably of 30-80, on the shore hardness scale A.

[0017] The flexible bending portion of the distal tip may define an effective applied force to deflection ratio and may be configured to prevent inadvertent tissue damage when advancing the surgical device along the lumen based on the shape of the distal end. The hardness may be selected for defining a pliable component. The flexible bending portion of the distal tip maybe integrally formed with the distal end and / or the proximal bending portion, which may feature similar hardness. Preferably the hardness is selected in combination with the shape of the distal tip, such that, when the distal end is deflected in response to a force insufficient to cause inadvertent tissue damage during normal use of the endoscope, the area of the resulting surfaces of the distal tip, when looking from an advancement direction of the distal head assembly, is larger than a maximum cross-sectional area of the distal head assembly proximal to the proximal mounting portion.

[0018] Based on the geometry of the distal tip, the effective stiffness of the proximal mounting portion may be larger than the stiffness of the flexible bending portion, such as to enable a transverse deflection of the distal end with respect to the proximal mounting portion. Theflexible bending portion may be configured to enable a deflection of the distal end by more than io% of a (maximum) transverse extension of the proximal mounting portion and / or the distal tip, such as by more than 20% of the transverse extension of the proximal mounting portion and / or the distal tip, e.g. 25% or 50% of the transverse extension of the proximal mounting portion and / or the distal tip, in response to abutment of the distal end against a soft tissue wall. For example, with an oval (e.g. circular, elliptical, or superelliptical) cross-section of the proximal mounting portion, the distal end may be deflected in a transverse direction by an amount equal to half of a radius or equal to a radius of the oval cross-section.

[0019] The flexible bending portion may comprise a flexible polymer body for enabling a deflection of the distal end in the transverse direction and / or for providing a soft contact surface. The material for the polymer body may be selected based on surgical considerations e.g. based on a desired softness and / or stiffness of the flexible tip based on the dimensions and application of the surgical device.

[0020] In some examples, the flexible bending portion comprises one or more of silicone, thermoplastic urethane, rubbers, isoprene based polymers and / or additively manufactured materials.

[0021] The distal end may be a distal end portion of the distal tip integrally formed with the flexible bending portion and may likewise be formed of or comprise a flexible polymer. As another example, the distal tip may be additively manufactured from light cured resins or laser sintered polymers. The additive manufacturing may allow forming an integral part with a varying effective stiffness, e.g. along the advancement direction of the endoscope head, wherein the material, material density and / or sub-structure of the distal tip maybe varied as part of the additive manufacturing process.

[0022] In some examples, the distal tip is additively manufactured as a single part along with the distal end portion of the endoscope from a configurable multi-stiffness material or from multiple materials.

[0023] The distal tip may form a cap with the distal end portion to be sleeved over an endoscope head. In some examples, the distal tip is integrally formed with a casing of the endoscope head.

[0024] In some examples, the flexible bending portion defines a bending mode of the distal tip in which the distal tip is deflected laterally to the advancement direction.

[0025] The flexible bending portion may be shaped to promote a lateral deflection of the distal tip as opposed to a longitudinal compression, such as to promote diverting forces applied along the advancements direction to prevent inadvertent tissue damage.

[0026] In some examples, a cross-section of the flexible bending portion along the extension of the distal tip is reduced with respect to a tissue engagement segment of the distal end, arranged distally with respect to the flexible bending portion.

[0027] For example, the distal tip may feature a curved tongue shape, which is curved with respect to the advancement direction, such as to present a laterally extending distal portion for providing a flat engagement surface against soft tissue in the advancement direction and to define a longitudinally extending portion connecting the laterally extending distal portion to the proximal mounting portion and defining a flexible bending portion.

[0028] As another example, the distal tip may feature a tapered shape, wherein a tapered segment, with a reduced cross-section, may define the flexible bending portion enabling a transverse deflection of the distal end.

[0029] The reduced cross-section in a segment of the distal tip may be arranged proximally with respect to a bulging tissue engagement segment, which may provide further haptic feedback when passing a constriction, e.g. of the lumen, and may facilitate control of the surgical device by a user.

[0030] In some examples, the (maximum) cross-section of the tissue engagement segment is equal to or larger than the (maximum) cross section of the proximal mounting portion of the distal tip, when viewed along the advancement direction.

[0031] In some examples, the flexible bending portion has a reduced diameter with respect to a bulging segment arranged between the distal end and the flexible bending portion, and optionally with respect to a segment of the proximal mounting portion arranged proximally with respect to the flexible bending portion.

[0032] The bulging segment may feature lateral dimensions which are larger than corresponding lateral dimensions of the flexible bending portion. For example, all lateraldimensions of the bulging segment with respect to the advancement direction may be larger than the corresponding dimensions of the flexible bending portion.

[0033] In some examples, the distal tip may feature an symmetric shape (e.g. axisymmetric) with respect to the advancement direction, wherein a diameter of the distal tip may vary along the advancement direction, e.g. with the first diameter associated with the proximal mounting portion, a second diameter associated with the flexible bending portion, and a third diameter associated with the tissue engagement segment, wherein the second diameter is smaller than the third diameter and the first diameter.

[0034] In some examples, a cross-section of the flexible bending portion is asymmetric with respect to an instrument axis of the distal tip.

[0035] The instrument axis of the distal tip may be a center axis of the distal tip, aligned normally and centered with respect to the proximal mounting portion. The proximal mounting portion may be connected to a distal end portion of the surgical device, such as to cover a distal end face of the surgical device, and the instrument axis may be aligned along a projection of the advancement direction of the distal end portion of the surgical device and centered with respect to a perimeter of the surgical device. In some examples, the instrument axis of the distal end is the longitudinal axis of the surgical device and aligned with a center of a distal end face of the surgical device.

[0036] The asymmetric cross-section of the distal tip with respect to the instrument axis may promote a transverse bending of the distal tip in response to a longitudinal abutment force on the distal end. For example, the flexible bending portion may be shifted in a first transverse direction from the instrument axis, such as to promote a bending of distal portions of the distal tip in the direction opposite the first transverse direction in response to a longitudinal abutment force, e.g. when the distal tip encounters an obstruction or constriction along the lumen.

[0037] The asymmetric arrangement of the flexible bending portion with respect to the instrument axis may promote a pre-defined transverse deflection direction of the distal end.

[0038] In some examples, a center of mass of the distal tip shifts with respect to the instrument axis between the distal tip and the flexible bending portion.

[0039] For example, the center of mass of a cross-section of the distal tip may shift from a laterally shifted position towards the instrument axis between the flexible bending portion and the distal tip.

[0040] A shifted and / or asymmetric cross-section of the distal tip with respect to the instrument axis close to the flexible bending portion may promote a rolling up motion of the distal tip in response to an abutment against a constriction, such as to increase a surface area engaging surrounding soft tissue and / or to define a ramp for deflecting the distal tip, e.g. when encountering an obstruction. The rolling up motion may further provide haptic feature when the distal end passes a constriction along the lumen, e.g. when the distal tip unrolls from a curled-up configuration.

[0041] In some examples, the distal tip comprises a curled tongue shaped section, wherein the curled tongue shaped section comprises the distal end and the flexible bending portion.

[0042] The curled tongue shape may extend from an off-axis location with respect to the instrument axis towards the distal end, which maybe arranged close to the instrument axis or opposite the instrument axis. The curled tongue shape maybe configured to define a deflection ramp for the surgical device, wherein the distal tip may be deflected in a pre-defined direction according to the curvature of the curled tongue shape of the distal tip, when the distal tip encounters an obstruction.

[0043] In some examples, the curled tongue shape section is configured to compress and / or roll up in response to a distal abutment of the distal end.

[0044] The curled tongue shape may dynamically increase a surface area, when compressed / rolled up, such as to reduce a likelihood of inadvertent tissue damage. A restoring force of the flexible bending portion may promote a deflection of the distal tip in a direction opposite the rolling up motion, which may induce visible tissue deflection for assisting a user.

[0045] In some examples, the curled tongue shaped section is configured to promote a predefined preferred deflection direction of the distal end.

[0046] The pre-defined preferred deflection direction may be aligned with an oblique camera view axis of the surgical device, such as to improve visual feedback to a user advancing the surgical device along the lumen. The pre-defined preferred deflection direction maybe aligned with a curvature of the curled tongue shaped section.

[0047] In some examples, when the distal end is deflected, the area of the resulting end face of the distal tip, when looking along an advancement direction of the distal tip, is larger than a maximum cross-sectional area of the proximal mounting portion.

[0048] For example, the distal tip may be configured to deflect by an amount that the effective surface area contacting soft tissue is increased beyond the cross-sectional area of the proximal mounting portion and / or of the distal head assembly prior to reaching a force threshold associated with inadvertent tissue damage. For example, the area of a resulting end face of the distal tip, when looking along the advancement direction, may be increased by at least 10% or 20%, in particular increased to be larger than 110% of 120% of the maximum cross-sectional area of the proximal mounting portion and / or of the distal head assembly.

[0049] The distal tip maybe connected to the surgical device by one or more of a form-fitting engagement, a force-fitting engagement, or a permanent fit, e.g. by gluing the distal end on a distal end face of the surgical device.

[0050] In some examples, the proximal mounting portion comprises a mounting feature configured for interlocking connection with a corresponding mounting feature on the distal end portion of the surgical device.

[0051] The distal tip may feature a (maximum) lateral extension adapted to the lateral extension, e.g. diameter, of the surgical device, such as a maximum lateral extension smaller than 25 mm or between 5 mm and 20 mm, e.g. between 10 mm and 15 mm.

[0052] According to a second aspect, a distal head assembly for a surgical device is provided that is to be inserted into a lumen of a human or animal body comprising the distal tip according to the first aspect and a view port for obtaining an image at the location of the distal head assembly.

[0053] The distal head assembly may feature channel connections for guiding surgical instruments to a location of the distal head assembly and / or may feature tools for accessing an intervention site, e.g. along the lumen. The distal head assembly may be configured as an endoscope head, such as a duodenoscope head. A camera may be arranged at the view port in the distal head assembly, e.g. proximally with respect to a mounting feature for mounting the distal tip.

[0054] In some examples, the distal tip is firmly bonded to a distal end portion of the surgical device. For example, the distal tip may be over- molded or glued onto the distal head assembly.

[0055] In some examples, a view axis of the view port is oblique to the advancement direction of the distal head assembly on the surgical device.

[0056] In duodenoscopes, a camera view angle may be oblique to the extension direction of the duodenoscope tube, e.g. in a side view configuration, for monitoring accessories passed to an intervention site by an elevator of the duodenoscope head.

[0057] The oblique camera view axis may prevent monitoring of the distal end of the surgical device. However, using the distal tip of the first aspect, navigating the lumen maybe facilitated by providing haptic feedback to a user, by providing visual feedback through a relative transverse deflection of the camera and surrounding tissue, e.g. when the distal end is deflected in a transverse direction while in contact with soft tissue, or by reducing the likelihood of inadvertent tissue damage, when the surgical device encounters an obstruction or constriction along the lumen.

[0058] In some examples, the flexible bending portion is configured to enable a deflection of the distal end towards the view axis.

[0059] For example, the flexible bending portion may be configured to define a preferred deflection direction of the distal end, e.g. based on an off-axis shift of the flexible bending portion with respect to the instrument axis, and the preferred deflection direction may be aligned with the camera view axis.

[0060] In some examples, a maximum cross-section of the distal tip along the advancement direction of the distal head assembly, in particular of the tissue engagement segment arranged between the distal end and the flexible bending portion, is equal to or larger than a maximum cross section of the distal head assembly.

[0061] In some examples, when the distal end is deflected, the area of the resulting end face of the distal tip, when looking from an advancement direction of the distal head assembly, is larger than a maximum cross-sectional area of the distal head assembly proximal to the proximal mounting portion.

[0062] The distal tip and the distal head assembly may be provided as a kit, and the distal tip may be exchangeable. In some examples, the distal tip and the distal head assembly may be provided as part of an endoscope kit, such as a duodenoscope kit.

[0063] According to a third aspect, an endoscope comprising the distal head assembly of the second aspect is provided. The endoscope may be a duodenoscope with a side viewing camera.DETAILED DESCRIPTION OF EMBODIMENTS

[0064] The features and numerous advantages of the devices and systems according to the present invention will best be understood from a detailed description of preferred embodiments with reference to the accompanying drawings, in which:Fig. 1 schematically illustrates an example of a distal head assembly of a surgical device that is to be inserted into a biological lumen of a human or animal body;Fig. 2A-D illustrate an example of a distal tip similar to the example of Fig. 1, with Fig. 2A illustrating a side view and Figs. 2B-D illustrating sectional views at different locations;Fig. 3 illustrates a schematic close-up view of an example of a distal tip on a distal head assembly, with the distal tip illustrated as a transparent element;Fig. 4 schematically illustrates another example of a distal head assembly; andFig. 5A-D illustrate an example of a distal tip similar to the example of Fig. 4, with Fig. 5A illustrating a side view and Figs. 5B-D illustrating sectional views at different locations.

[0065] Fig. 1 schematically illustrates an example of a distal head assembly 10 of a surgical device, specifically an endoscope, that is to be inserted into a biological lumen of a human or animal body (not shown). The distal head assembly 10 comprises a si de-vi ewing camera arranged at a camera view port 12 and light output port 13 for monitoring an access site along the biological lumen and an elevator 14 for displacing accessories into a camera field of view of the camera view port 12. The accessories may be fed and / or controlled through channels connected to the distal head assembly 10 via an endoscope connection 16. The channels may comprise channels for applying a suction force or for an air / water provision system, e.g. forlens cleaning and insufflation. The light output port 13 may provide light supplied from a proximal portion of the endoscope and / or may be coupled to a lighting device arranged in the distal head assembly 10.

[0066] The distal head assembly 10 may be arranged at a distal end portion of the endoscope, such as a duodenoscope, and can be introduced into the biological lumen along an advancement direction 18 of the endoscope through the biological lumen. The advancement direction 18 maybe a projection of a longitudinal axis of a cylindrical tube of the endoscope at the tube’s distal end and may follow a natural geometry of the biological lumen as the surgical device is advanced towards an access site for viewing and / or treating soft tissue.

[0067] The distal head assembly 10 is connected to a distal tip 20 arranged at a distal end portion 22 of the distal head assembly 10, wherein the distal tip 20 may be mounted on the distal end portion 22 of the distal head assembly 10 at a proximal mounting portion 24. The distal tip 20 extends along the advancement direction 18 from the proximal mounting portion 24 to a distal end 26, with a flexible bending portion 28 arranged between the distal end 26 and the proximal mounting portion 24.

[0068] The distal tip 26 is configured to engage soft tissue distal to the endoscope, as the distal head assembly 10 is advanced through the biological lumen along the advancement direction 18. In the illustrated example, the distal tip 20 features a J-shape or curled tongue shape extending from the proximal mounting portion 24 to the distal end 26. A tissue engagement segment of the distal tip close to the distal end 26 extends oblique to the advancement direction 18, while the flexible bending portion 28 extends substantially along the advancement direction 18, such that the distal tip 20 extends at an angle with respect to the advancement direction 18 close to the distal end 26.

[0069] When the distal tip 20 encounters an obstruction in the biological lumen, such as a stomach wall, the distal end 26 may be deflected in a transverse direction about the flexible bending portion 28, wherein the distal end 26 may be deflected transversally to the advancement direction 18 and opposite to the advancement direction 18.

[0070] The curled tongue shape of the distal tip 20 can enable a rolling up motion of the distal tip 20 when the distal end 26 engages an obstruction as the distal head assembly 10 is advanced through the biological lumen. As part of the rolling up motion of the distal tip 20, the distalend may be deflected transversally with respect to an extension of the distal tip 20, as the flexible bending portion 28 is deformed in response to an abutment force.

[0071] The deflection of the distal end 26 may increase an effective surface engaged with surrounding soft tissue at the obstruction. In some examples, the distal end 26 features a tapered shape, and a cross-section of the distal tip 20 along its extension may progressively increase from the distal end 26 to the flexible bending portion 28.

[0072] In addition, the curled tongue shape of the distal tip 20 may further define a deflection ramp for deflecting the distal head assembly 10 and the surrounding tissue transversally with respect to each other according to a curvature of the curled tongue shape. The curvature of the distal tip may be aligned with a viewing direction 32 of the side-viewing camera view port 12, such as to provide visual feedback of engaging the obstruction to a user.

[0073] In some examples, the tongue curvature can act like a ramp to facilitate a deflection of the distal end 26 in a specific direction when an anatomical limit is reached. For example, in the example illustrated in Fig. 1, a contact between tissue and the distal tip 20 will tend to deflect the distal head assembly 10 forward into the viewing direction 32 of the side-viewing camera view port 12.

[0074] In the illustrated example, the flexible bending portion 28 is shifted in a transverse direction with respect to an instrument axis 30 of the distal head assembly 10. The instrument axis 30 extends along the advancement direction 18 and is arranged in a center of the distal head assembly 10. The instrument axis 30 may be aligned with a momentum vector of the distal head assembly 10 as the distal head assembly 10 is advanced through a biological lumen on a tube of an endoscope.

[0075] Fig. 2A-2D illustrate an example of a distal tip 20 similar to the example of Fig. 1, wherein Fig. 2A illustrates a side view of the distal tip 20, while Figs. 2B-2D illustrate cross- sectional views of the distal tip 20 of Fig. 2A through the planes indicated with letters B-D respectively, extending perpendicular to the instrument axis 30. The cross-sectional views in Fig. 2B-2D are centered on the instrument axis 30 with the x-axis extending into the plane of projection of Fig. 2A and the y-axis extending perpendicularly to the x-axis and the instrument axis 30.

[0076] As illustrated in Fig. 2B, the distal tip 20 may feature an oval cross-section close to the proximal mounting portion, which maybe similar to a cross-section of the distal head assembly 10 shown in Fig. 1.

[0077] As schematically illustrated in Fig. 2C, in the flexible bending portion 28, the distal tip 20 may extend substantially parallel to the instrument axis 30, and may feature a cross-section with a smaller area than at the proximal mounting portion, while a center of mass of the crosssection can be shifted with respect to the instrument axis 30 (at the center of the coordinate system of Fig. 2C).

[0078] A thickness of the flexible bending portion 28 may be smaller than 50% of a maximum lateral extension of the distal tip 20 at the proximal mounting portion 24, e.g. smaller than 40% or smaller than 30% of the maximum lateral extension of the distal tip 20 at the proximal mounting portion 24. For example, for an endoscope with a maximum lateral extension of about 13 mm, the thickness of the flexible bending portion 28 may be smaller than 5mm, such as smaller than 4 mm or 3mm, e.g. 1 mm or 2 mm. The thickness of the flexible bending portion 28 may be the lateral extension of a cross-section of the flexible bending portion 28, when viewed along the instrument axis 30.

[0079] From the section of the flexible bending portion 28 illustrated in Fig. 2C, the distal tip 20 may curve towards the instrument axis 30, such that the distal tip 20 may extend obliquely to the instrument axis 30 close to the distal end 26 of the distal tip 20.

[0080] The cross-section perpendicular to the instrument axis 30 illustrated in Fig. 2D may feature a larger area than the cross-section of the distal tip 20 illustrated in Fig. 2C in the flexible bending portion 28 of the distal tip 20. The increased cross-section close to the distal end 26 may correspond to an increased contact area for engaging soft tissue, e.g. of a surrounding lumen, and may provide haptic feedback, when passing a constriction of a biological lumen.

[0081] Based on the arrangement of the flexible bending portion 28 shifted in the transverse direction as shown in Figs. 1, 2A-2D, a preferred deflection direction may be defined, which may be aligned with the curvature of the distal tip 20 having the curled tongue shape. As a result, the distal end 26 may be preferentially deflected in the preferred deflection direction, which may be a direction opposite to the transverse direction in which the flexible bending portion 28 is shifted.

[0082] The preferred deflection direction may be aligned with, e.g. parallel or perpendicular to, the viewing direction 32 of the camera view port 12, such as to improve visual feedback when the distal tip 20 encounters an obstruction during an advance of the distal head assembly 10 through the biological lumen.

[0083] The skilled person will appreciate that based on the shape of the distal tip 20, the distal tip 20 may also be axially compressible tip, which may result in a larger / flatter and increased surface area than what is possible with a rigid rounded tip.

[0084] The skilled person will further appreciate that the distal tip 20 may in principle be flexible in all lateral directions, and the preferred deflection direction may merely be defined by different effective stiffness coefficients for different deflection directions, when the distal tip 20 engages a certain obstruction geometry, such as an obstruction abutting longitudinally against the distal tip 20.

[0085] The distal tip 20 may be integrated with other components of the distal head assembly 10, e.g. as an over-molded feature or as a multi-durometer 3D printed part. In some examples, the distal tip 20 is a separate part which is fixedly connected with, e.g. glued onto, the distal end portion 22 of the distal head assembly 10. In some examples, the distal tip 20 is fit on a rigid mounting geometry of the distal head assembly 10 in addition to or as an alternative to an integral / glued connection.

[0086] Fig. 3 illustrates a schematic close-up view of an example of a distal tip 20 on a distal head assembly 10, with the distal tip 20 illustrated as a transparent element. The distal tip 20 is mounted on the distal end portion 22 of the distal head assembly 10 at the proximal mounting portion 24, wherein the distal end portion 22 of the distal head assembly 10 features an interlocking mounting geometry 34 interlocking with a corresponding recess of the distal tip 20 to retain the distal tip 20 in place on the distal end portion 22 of the distal head assembly 10.

[0087] The interlocking mounting geometry 34 may feature transverse protrusions, such as the barbed features illustrated in Fig. 3, which may interlock with corresponding cavities of the distal tip 20 for preventing relative rotation of the distal tip 20 and the distal head assembly 10. The interlocking mounting geometry 34 may maintain a predefined orientation of the distal tip 20 to the camera viewport 12, such as to provide consistent visual and / or haptic feedback to a user of the surgical device.[oo88] The skilled person will appreciate that, although the distal tip 20 is illustrated as having a recess for interlocking with a protruding mounting geometry 34 arranged at a distal end portion 22 of the distal head assembly 10, the distal tip 20 may also comprise a protruding interlocking shape to engage and interlock with a corresponding recessed shape of the distal end portion 22.

[0089] Moreover, although the distal tip 20 is illustrated as a component mounted to a distal end face of the distal head assembly 10 in the examples of Figs. 1-3, the distal tip 20 may also be implemented as an extension of a fixed or removable cap that shrouds multiple features of the distal head assembly 10.

[0090] In some examples, the distal tip 20 is part of a shrouding tip laterally shrouding portions of the distal head assembly 10 housing the camera view port 12 and / or the elevator 14. In some examples, the shrouding tip comprises a mounting feature engaging with the distal head assembly 10 in a transverse direction to retain the shrouding tip in place on the distal head assembly 10. For example, the shrouding tip may snap onto the distal head assembly 10 for laterally shrouding portions of the distal head assembly 10.

[0091] Fig. 4 schematically illustrates another example of a distal head assembly 10 of a surgical device that is to be inserted into a biological lumen of a human or animal body (not shown). The distal head assembly 10 is similar to the example illustrated in Fig. 1, but differs in the shape of the distal tip 20.

[0092] In the example of Fig. 4, the distal tip 20 also features a proximal mounting portion 24 for mounting the distal tip 20 on the distal end portion 22 of the distal head assembly 10, and the distal tip 20 extends along the advancement direction 18 from the proximal mounting portion 24 to a distal end 26. Between the distal end 26 and the proximal mounting portion 24, the distal tip 20 features a tapered segment implementing a flexible bending portion 28 enabling transverse deflection of the distal end 26 with respect to the advancement direction 18.

[0093] Distally with respect to the tapered segment, the distal tip 20 features a bulging tissue engagement segment 36 arranged proximally to the distal end 26. The bulging tissue engagement segment 36, may be ball-shaped and features a larger maximum lateral extension, e.g. diameter, than the tapered segment associated with the flexible bending portion 28.

[0094] A ball (or similar) shape located at the distal tip 20, placed after a tapered transition can serve as an initial landmark providing haptic feedback to a user. When the advancement of the bulging tissue engagement segment 36 through a particular anatomy can be felt, the tapered shank behind it can give the user the perception of passing an initial landmark because the next features must be advanced through a narrow pass.

[0095] Moreover, the lateral and longitudinal extension of the tapered segment implementing the flexible bending portion 28 may be configured to enable a transversal deflection of the distal tip 20. The transversal deflection of the bulging tissue engagement segment 36 may dynamically increase an effective surface area contacting an obstruction along the advance of the surgical device in the lumen, which may reduce a likelihood of inadvertent tissue damage. In addition, the transverse deflection of the distal end may divert forces from a soft tissue wall, which may further reduce the likelihood of inadvertent tissue damage, or facilitate a passive adaption of the shape of the distal tip to the geometry of the surrounding lumen.

[0096] Fig. 5A-5D illustrate an example of a distal tip 20 similar to the example of Fig. 4, wherein Fig. 5A illustrates a side view of the distal tip 20, while Figs. 5B-5D illustrate cross- sectional views of the distal tip 20 of Fig. 5A through the planes indicated with letters B-D respectively, extending perpendicular to the instrument axis 30. The cross-sectional views in Fig. 5B-5D are centered on the instrument axis 30 with the x-axis extending into the plane of projection of Fig. 5A and the y-axis extending perpendicularly to the x-axis and the instrument axis 30.

[0097] As illustrated in Fig. 5B, the distal tip 20 may feature an oval cross-section close to the proximal mounting portion 24, which may be similar to a cross-section of the distal head assembly 10. In the example of Fig. 5B, the cross-section of the distal tip 20 is approximately circular with a diameter, which may be similar to a lateral extension of the distal head assembly 10 on which the distal tip 20 is mounted.

[0098] As illustrated in Fig. 5C, in the flexible bending portion 28, the distal tip 20 may be tapered featuring a smaller diameter than at the proximal mounting portion 24, while retaining a substantially circular shape.

[0099] As illustrated in Fig. 5C, the bulging tissue engagement segment 36 may feature a circular cross-section with a diameter which is larger than the diameter of the distal tip 20 inthe flexible bending portion 28, such that a stiffness of the flexible bending portion 28 maybe smaller than a stiffness of the bulging tissue engagement segment 36.

[0100] Apart from enabling a transverse deflection of the bulging tissue engagement segment 36 about the flexible bending portion 28, the variation of the lateral extension of the distal tip 20 along the advancement direction 18 may improve haptic feedback to the user when passing restrictions along the lumen.

[0101] The ball-shape of the bulging tissue engagement segment 36 illustrated in the examples of Figs. 4, 5A-D may provide a smooth tissue engagement segment for varying diameters of the surrounding lumen, but other shapes may be used in implementations. For example, the bulging tissue engagement segment 36 may be provided with a pointed tip at the distal end 26, e.g. to facilitate entry and dilation into small spaces, e.g. if the hardness of the material is small enough to prevent inadvertent perforation of soft tissue.

[0102] In some examples, a curvature of the distal end is larger than a radius of the proximal mounting portion 24, such as to facilitate advance of the distal tip 20 into orifices with smaller lateral dimensions.

[0103] The bulging tissue engagement segment 36 can be sized in relation to the surgical device’s largest features, such that a haptic feedback to the user may give an indication to the user of the size of the surgical device in relation to the narrowest orifice of entry.

[0104] For a lateral extension of the bulging tissue engagement segment 36 greater than the surgical device, a haptic feedback to the user may indicate that if the bulging tissue engagement segment 36 is insertable, the other portions of the surgical device may advance through the lumen without expected complications.

[0105] For a lateral extension of the bulging tissue engagement segment 36 being nominally sized, e.g. of similar diameter, with respect to a maximum lateral extension of the surgical device, a characteristic haptic feedback to the user may indicate that a similar difficulty is to be expected when advancing the surgical device.

[0106] For a lateral extension of the bulging tissue engagement segment 36 smaller than the maximum lateral extension of the surgical device, a characteristic haptic feedback to the user may indicate that if the distal tip 20 is difficult to advance, the rest of the scope will experience even more resistance, wherein the distal tip 20 may act as an advance probe.

[0107] The skilled person will appreciate that although the examples of Figs. 4, 5A-D illustrate examples with a circular cross-section, other examples may feature non-circular crosssections, such as oval cross-sections for providing a smooth perimeter adapted to a shape of a duodenoscope head. In some examples, the distal tip 20 features a superelliptic cross-section, e.g. at the proximal mounting portion 24, which may approximate a rectangular shape with rounded edges. Moreover, the shape of the cross-section may vary along the advancement direction, e.g. to promote a pre-defined preferred deflection direction of the bulging tissue engagement segment 36 about the flexible bending portion 28.

[0108] In the examples of Figs. 4, 5A-D, the proximal mounting portion 24, the flexible bending portion 28, and the distal end 26 are substantially axisymmetric with respect to the instrument axis 30. However, in some examples, the distal end 26 and / or the flexible bending portion 28 may also be arranged off-axis, such as to promote a preferred deflection direction of the distal end 26, e.g. towards the camera viewport 12.

[0109] In some examples, aspects of the examples in Fig. 1-3 and the examples of Figs. 4, 5A- D may be combined, such as to include a bulging tissue engagement segment 36 arranged distally to an off-axis flexible bending portion 28, which may be tongue shaped, such as to combine advantageous effects of different examples.

[0110] According to the third aspect, as mentioned above, an endoscope comprising the distal head assembly of the second aspect is provided. The endoscope may comprise a camera, which can be arranged within the endoscope as a side-viewing or side-facing camera. In particular, the endoscope may be a duodenoscope with a side viewing camera.

[0111] In the case of a side-facing camera, the endoscope can be particularly well suited to carry out Endoscopic retrograde cholangio-pancreatography (ERCP) applications, such as in the context of bile duct and pancreatic duct access, e.g. for observation or surgery. When using a side-viewing camera, the advancement direction of the endoscope within a lumen of the human or animal body preferably may not coincide with the viewing direction of the endoscope. For example, the advancement direction and the viewing direction of the side-viewing camera may enclose an angle, which can be in a range of 60 to 120 degrees, preferably between 70 and 110 degrees, more preferably between 80 and too degrees and most preferably in the vicinity of 90 degrees. In the latter case, the side-viewing camera may be arranged within the endoscope so that the viewing direction of the camera is basically perpendicular to the advancement direction of the endoscope.

[0112] It is noted that the distal tip of the present invention, in at least some examples, does not comprise openings for the delivery surgical tools or occluding device. The distal tip according to the present invention may be designed in a blunt way. This being blunt can e.g. be achieved by the rigid portion of the distal tip and / or the camera of the endoscope being a side-facing camera. In the latter case, the endoscope may not have front facing exit ports, which may cause damage to tissue or other parts of the human or animal body.

[0113] One of the advantageous effects, which can be achieved with the distal tip according to the present invention, is that the distal tip may create - through its built-up and its capacity to transversely deflect - a broader surface at the distal tip compared to the already blunt front face of the distal end. By being transversely deflectable, the cross-section of the distal tip can be enlarged, so that the distal tip becomes more blunt, when getting in contact with tissue or mucosa. This approach differs from conventional devices, such as catheters or delivery devices described in the prior art, which glance off of walls at a shallow angle of attack, because their diagonal cut opening may easily dig into the mucosa or other tissues. According to the present invention, an already blunt distal tip is modified in order to create a geometry, which can expand to make the distal tip and / or the cross-section of the distal tip even larger than the original size of the endoscope, specifically when pushing against tissue at more perpendicular angles of attack. Thus, the distal tip becomes even more blunt or soft. Catheters or delivery devices, as described in the prior art, can be delivered through endoscopes or their working channels. They therefore represent accessory instruments, which may be deployed through an endoscope, in particular endoscopes having a front-facing camera. Such accessory instruments often have tips, which needs protection, whereas endoscopes do not use to have sharp tips, for which protection with regard to the lumen of tissue of human or animal body is required.

[0114] The description of the preferred embodiments and the figures merely serve to illustrate the invention and the beneficial effects associated therewith, but should not be understood to imply any limitation. The scope of the invention is to be determined solely by the appended claims.LIST OF REFERENCE SIGNS10 distal head assembly12 camera view port14 elevator16 endoscope connection18 advancement direction20 distal tip22 distal mounting portion of the distal head assembly 24 proximal mounting portion of the distal tip26 distal end28 flexible bending portion30 instrument axis32 camera view direction 34 interlocking mounting geometry36 bulging tissue engagement segment

Claims

CLAIMS1. A distal tip (20) for an endoscope that is to be inserted into a lumen of a human or animal body, the distal tip (20) comprising: a proximal mounting portion (24) for the connection of the distal tip (20) to a distal end portion (22) of the endoscope; a distal end (26) of the distal tip (20) to engage soft tissue distal to the endoscope during an advance of the endoscope; and a flexible bending portion (28) arranged between the distal end (26) and the proximal mounting portion (24) and configured to enable a transverse deflection of the distal end (26) with respect to the proximal mounting portion (24).

2. The distal tip (20) of claim 1, wherein the flexible bending portion (28) is integrally formed with the distal end (26) and / or the proximal mounting portion (24).

3. The distal tip (20) of claim 1 or 2, wherein the flexible bending portion (28) comprises one or more of silicone, thermoplastic urethane, rubbers, isoprene based polymers or additively manufactured materials; and / or wherein the distal tip (20) is additively manufactured as a single part along with the distal end portion (22) of the endoscope from a configurable multi-stiffness material or from multiple materials.

4. The distal tip (20) of any one of the preceding claims, wherein the flexible bending portion (28) defines a bending mode of the distal tip (20) in which the distal tip (20) is deflected laterally to an advancement direction (18) of the distal tip (20).

5. The distal tip (20) of any one of the preceding claims, wherein a cross-section of the flexible bending portion (28) along the extension of the distal tip (20) is reduced with respect to a tissue engagement segment (36) of the distal end (26), arranged distally with respect to the flexible bending portion (28).

6. The distal tip (20) of any one of the preceding claims, wherein the flexible bending portion (28) has a reduced diameter with respect to a bulging segment arranged between the distal end (26) and the flexible bending portion (28), and optionally with respect to a segment of the proximal mounting portion (24) arranged proximally with respect to the flexible bending portion (28).

7. The distal tip (20) of any one of the preceding claims, wherein a cross section of the flexible bending portion (28) is asymmetric with respect to an instrument axis (30) of the distal tip (20); and / orwherein a center of mass of the distal tip shifts with respect to the instrument axis (30) between the distal tip (20) and the flexible bending portion (28).

8. The distal tip (20) of any one of the preceding claims, wherein the proximal mounting portion (24) comprises a mounting feature configured for interlocking connection with a corresponding mounting feature on a distal end portion (22) of the endoscope.

9. The distal tip (20) of any one of the preceding claims, wherein the distal tip (20) comprises a curled tongue shaped section, wherein the curled tongue shaped section comprises the distal end (26) and the flexible bending portion (28), wherein the curled tongue shape section is optionally configured to compress and / or roll up in response to a distal abutment of the distal end (26).

10. A distal head assembly (10) for an endoscope that is to be inserted into a lumen of a human or animal body comprising the distal tip (20) according to any one of the preceding claims and a view port (12) for obtaining an image at the location of the distal head assembly (10).

11. The head assembly (10) of claim 10, wherein a maximum cross-section of the distal tip (20) along the advancement direction (18) of the distal head assembly (10), in particular of a tissue engagement segment (36) arranged between the distal end (26) and the flexible bending portion (28), is equal to or larger than a maximum cross section of the distal head assembly (10); and / or wherein, when the distal end (26) is deflected, the area of a resulting end face of the distal tip (20), when looking along an advancement direction (18) of the distal head assembly (10), is larger than a maximum cross-sectional area of the distal head assembly (10) proximal to the proximal mounting portion (24).

12. The distal head assembly (10) of claim 10 or 11, wherein the distal head assembly (10) comprises a camera arranged at the view port (12).

13. The distal head assembly (10) of any one of claims 10 to 12, wherein a view axis of the view port (12) is oblique to an advancement direction (18) of the distal head assembly (10) on the endoscope, wherein the flexible bending portion (28) is optionally configured to enable a deflection of the distal end (26) towards the view axis.

14. The distal head assembly (10) of any one of claims 10 to 13, wherein the distal tip (20) is firmly bonded to a distal end portion (22) of the endoscope.

15. An endoscope comprising the distal tip (20) of any one of claims 1-9 or the distal head assembly (10) of any one of claims 10-14.

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