Tubular tissue transformer

Abstract

To provide a tubular tissue transformer for a tubular tissue structure, and related tools and methods.SOLUTION: A tubular tissue transformer (TTT) for a tubular tissue structure has a plurality of leaves and a plurality of retainers on each of the leaves. Each retainer retains the tubular tissue structure on the respective leaf. Also provided are a coupling system for coupling tubular tissue structures together, and tools and methods for attaching and widening tubular tissue structures.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates generally to tubular tissue deformers for tubular tissue structures and related tools and methods. [Background technology]

[0002] In surgery, tissue structures may be joined to form an anastomosis. Traditionally, this has required hand-suturing the tissue structures, which can be time-consuming, risky, and demanding, requiring extensive training and great precision.

[0003] Devices for assisting in the joining of tissue structures may hold the tissue structures together with large fixation pins that are attached to the tissue structures one by one. However, some tissue structures may tear when subjected to the strain associated with attachment to those pins. This can be particularly problematic for relatively thick-walled or inflexible tissue structures, such as arteries.

[0004] To ensure good contact between the inner surfaces of the tissue structures for healing, the tissue structures may be everted before being joined together. In some circumstances, this may cause damage to the tissue structures by excessively deforming them and preventing anastomosis. This may be particularly problematic for relatively thick-walled or inflexible tissue structures, such as arteries. In some circumstances, it may be difficult to provide an appropriately shaped surface to maintain good contact between the inner surfaces of the joined tissue structures. Summary of the Invention

[0005] According to one exemplary embodiment, there is provided a tubular tissue deformer for a tubular tissue structure, comprising: a plurality of leaves; a plurality of retainers on each of the plurality of leaves, each retainer configured to hold a tubular tissue structure on a respective leaf; A tubular tissue deformer is provided comprising:

[0006] According to another exemplary embodiment, there is provided a method of attaching a tubular tissue structure to a tubular tissue deformer, comprising: A method is provided that includes compressing a portion of a tubular tissue structure to simultaneously hold the tubular tissue structure in multiple positions.

[0007] According to another exemplary embodiment, there is provided a tubular tissue deformer for a tubular tissue structure, comprising: a plurality of leaves configured to hold an everted portion of the tubular tissue structure; a bushing configured to be movable between a first position and a second position and configured to support an outer surface of the everting portion of the tubular tissue structure when in the second position; A tubular tissue deformer is provided comprising:

[0008] According to another exemplary embodiment, everting a portion of the tubular tissue structure; supporting an outer surface of the everting portion of the tubular tissue structure on a surface that curves outwardly away from the center of the everting portion; A method is provided that includes:

[0009] According to another exemplary embodiment, there is provided a device for expanding a portion of a tubular tissue structure held on a tubular tissue deformer around an opening in the tubular tissue deformer, the device comprising: A tool is provided that includes a tapered portion for insertion into the opening to widen the opening and thereby widen a portion of the tubular tissue structure.

[0010] According to another exemplary embodiment, there is provided a device for expanding a portion of a tubular tissue structure held on a tubular tissue deformer around an opening in the tubular tissue deformer, the device comprising: A device is provided that includes an expandable portion for insertion into the opening and expansion within the opening to enlarge the opening and thereby enlarge a portion of the tubular tissue structure.

[0011] According to another exemplary embodiment, there is provided a method of radially expanding a portion of a tubular tissue structure, comprising: holding a portion of the tubular tissue structure at a first diameter; deforming a portion of the tubular tissue structure to a second diameter greater than the first diameter while the portion of the tubular tissue structure is held; holding a portion of the tubular tissue structure having a second diameter; A method is provided that includes:

[0012] According to another exemplary embodiment, there is provided a tubular tissue deformer for a tubular tissue structure, comprising: one or more leaves positioned about the passage of the tubular tissue deformer and configured to retain a portion of the tubular tissue structure; a bushing configured to be at least partially positionable within the passageway; A tubular tissue deformer comprising: A tubular tissue deformer is provided in which the bushing is at least partially plastically deformable to radially expand one or more leaves and to retain the leaves in a radially expanded state.

[0013] According to another exemplary embodiment, there is provided a system for joining tubular tissue structures, comprising: a first tubular tissue deformer having one or more retainers for retaining a portion of the tubular tissue structure, the one or more retainers being positioned at one or more retainer locations around the retained portion of the tubular tissue structure; a second tubular tissue deformer having one or more retainers for retaining a portion of the tubular tissue structure, the one or more retainers being positioned at one or more retainer locations around the retained portion of the tubular tissue structure; a first coupling device; a second coupling device configured to couple to the first coupling device; A system comprising: the first coupling device and the second coupling device are configured to couple the retaining portions of the tubular structure and maintain a predetermined rotational offset between the one or more retainer positions of the first tubular tissue deformer and the one or more retainer positions of the second tubular tissue deformer; A system is provided in which the rotational offset is an offset about a longitudinal axis through the coupling device when the holding portions are coupled.

[0014] According to another exemplary embodiment, An attachment tool is provided that includes a deformable surface configured to press a portion of the tubular tissue structure against a plurality of retainers of the tubular tissue deformer to attach the portion of the tubular tissue structure to the tubular tissue deformer.

[0015] The embodiments may be implemented according to any of the dependent claims.

[0016] It is recognized that the terms "comprise," "comprises," and "comprising" can have exclusive or inclusive meanings in various jurisdictions. For purposes of this specification, and unless otherwise specified, these terms are intended to have an inclusive meaning, i.e., they are to be interpreted to mean the inclusion of the recited components to which their use is directly referred, and possibly other unspecified components or elements.

[0017] The mention of a document in this specification is not an admission that it is prior art, that it may be usefully combined with other documents, or that it forms part of the common general knowledge.

[0018] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the foregoing summary of the invention and the following detailed description of the embodiments, serve to explain the principles of the invention. [Brief explanation of the drawings]

[0019] [Figure 1A]FIG. 1 is a perspective view of a tubular tissue deformer according to one embodiment in an unexpanded, resting state. [Figure 1B] 10A-10C are perspective views of exemplary alternative configurations of tubular tissue deformers. [Figure 2A] 2 is a perspective view of the tubular tissue deformer of FIG. 1 in an expanded state. [Figure 2B] FIG. 1C is a perspective view of the tubular tissue deformer of FIG. 1B in an expanded state. [Figure 3A] FIG. 2B is an exploded view of the tubular tissue deformer of FIGS. 1A and 2A. [Figure 3B] FIG. 2C is an exploded view of the tubular tissue deformer of FIGS. 1B and 2B. [Figure 4] 1 is a cross-sectional view of a tubular tissue deformer according to one embodiment. [Figure 5] FIG. 1 is a perspective view of a tubular tissue deformer and a tubular tissue structure positioned within a passageway of the tubular tissue deformer, according to one embodiment. [Figure 6] FIG. 1 is a perspective view of a tubular tissue deformer and a tubular tissue structure held on the tubular tissue deformer, according to one embodiment. [Figure 7] FIG. 1 is a perspective view of a tubular tissue deformer and an everted tubular tissue structure on the tubular tissue deformer, according to one embodiment. [Figure 8A] 1 is a perspective view of a system for joining tubular tissue structures according to one embodiment. [Figure 8B] 1 is a perspective view of an exemplary alternative system for joining tubular tissue structures. [Figure 9A] FIG. 8B is an exploded view of the system of FIG. 8A. [Figure 9B] FIG. 9 is an exploded view of an exemplary alternative to the system of FIG. 8. [Figure 9C] FIG. 8C is an exploded view of the system of FIG. 8B. [Figure 10] FIG. 1 is a perspective view of a tubular tissue deformer, a coupling device, and a tubular tissue structure according to one embodiment. [Figure 11] 9 is a perspective view of a system for joining tubular tissue structures and the tubular tissue structures of FIG. 8. FIG. [Figure 12] 1 is a cross-sectional view of a tubular tissue structure inserted into a tubular tissue deformer according to one embodiment. [Figure 13] 13 is a cross-sectional view of a tool operating on the inserted tubular tissue structure of FIG. 12 according to one embodiment. [Figure 14] 14 is a cross-sectional view of the tool of FIGS. 12 and 13 operating on a tubular tissue structure to attach the tubular tissue structure to a tubular tissue deformer according to one embodiment. [Figure 15] 1A is a cross-sectional view of a tubular tissue deformer in an unexpanded, resting state and a tubular tissue structure held on the tubular tissue deformer, according to one embodiment. [Figure 16] 16 is a cross-sectional view of the tubular tissue deformer of FIG. 15 in an expanded state and the tubular tissue structure of FIG. 15 everted over the tubular tissue transducer according to one embodiment. [Figure 17] 1A-1C are cross-sectional views of a tubular tissue deformer and an implement acting on a tubular tissue structure held on the tubular tissue deformer, according to one embodiment. [Figure 18] 18 is a cross-sectional view of the tool of FIG. 17 operating on a bushing of the tubular tissue deformer of FIG. 17 to deform the bushing according to one embodiment. [Figure 19] 1 is a partial cross-sectional view of a tubular tissue structure and a system for joining the tubular tissue structure according to one embodiment. [Figure 20] 20 is a partial cross-sectional view of the system and tubular tissue structure of FIG. 19 with a tubular tissue deformer of the system engaged with a coupling device of the system according to one embodiment. [Figure 21] 21 is a cross-sectional view of the system and tubular tissue structure of FIGS. 19 and 20, with a coupling device coupled to the tubular tissue structure according to one embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0020] The present application relates to a tubular tissue deformer (TTT) having leaves, bushings, and retainers. Each leaf has two or more retainers. The retainers may allow the tubular tissue structure to be attached to two or more retainers simultaneously, rather than attaching the tubular tissue structure to the retainers one by one. This may simplify and speed up the attachment of the tissue structure.

[0021] The bushing is further designed to evert the tissue structure by expanding the leaves and support the outer surface of the everted tissue structure, which may provide a large, well-supported surface of the tissue structure for attachment to another tissue structure and may reduce damage to the tissue structure during eversion.

[0022] The present application further relates to devices and methods for assisting in the attachment of tissue structures and for expanding the diameter of tissue structures, as well as systems for coupling tubular tissue deformers to tubular tissue structures.

[0023] The following terms are used throughout:

[0024] Tubular tissue deformer (TTT) is a device that deforms tissue structures to facilitate anastomosis. It may also optionally hold, evert, and / or change the diameter of the tissue structure. It may also optionally maintain the integrity of the tissue structure during one or more of these processes. References throughout this specification and claims to a tubular tissue deformer or TTT should be understood to refer to such a device.

[0025] Tubular tissue structure: A part of the human or other animal body formed from tissue, which is a structure having a lumen and is generally tubular in shape. Examples include blood vessels (e.g., veins, arteries, lymphatic vessels, ureters, pancreatic ducts, intestines, and other ducts).

[0026] Leaf A part of an object that extends beyond another part of the object and has a significant width across its length at at least one location along its length.

[0027] Bush A member positioned on the inner periphery of a passage or opening.

[0028] Everting: In the context of tubular tissue structures, means turning outward so that the inner surface of the tissue structure around the lumen is accessible for contact. Derived terms such as "everting" and "everted" have this same meaning.

[0029] Anastomosis A circumferential connection between tubular tissue structures.

[0030] An exemplary tubular tissue deformer (TTT) 1 is shown in Figures 1A, 2A, and 3A. The device 1 has leaves 2, each of which is provided with a retainer 3. In this embodiment, the TTT 1 further includes a bushing 4. In Figure 1A, the device 1 is in a first configuration with the leaves 2 in a rest position and the bushing 4 in a non-advanced position. Figure 2A shows the same device 1 in a second configuration with the leaves 2 in an expanded configuration and the bushing 4 in an advanced position.

[0031] Each of the leaves 2 in this embodiment has multiple retainers that hold the attached tubular tissue structure. Having more than one retainer on each leaf 2 may be considered a disadvantage in conventional devices that require individual attachment of the tissue structure to each retainer. However, the retainers on each leaf of the TTT1 of the present invention are designed to simultaneously attach and hold the tissue structure in one step, without requiring individual attachment to each retainer. This may reduce the time, skill, and expertise required to attach the tissue structure to the retainers.

[0032] The retainer can be a suction port, a pin, a gripper, or other element that can be attached to the tissue structure. In the example of FIG. 1A, the retainer is a pin 3. The pin 3 can be straight or curved outward. By outward, we mean angled from the longitudinal axis 19 through the TTT 1, which is generally aligned with the extension of the leaves 2. The retainer can also be a combination of some straight pins and some curved pins. In some applications, straight pins may be easier to push into the tissue structure. In some applications, curved pins may better hold the tissue structure and reduce the chance of it becoming dislodged from the TTT 1. The straight pins can extend at an angle from the longitudinal axis 19. A combination of straight pins at different angles is possible.

[0033] The length of the pins 3 in this embodiment is 0.2 mm to 1.5 mm, for example, 0.5 mm to 1.2 mm. Pins 3 of different lengths may be suitable for different applications, such as different tissue structures. For example, short pins may be more suitable for attachment to small or thin-walled structures, while long pins may be more suitable for attachment to large or thick-walled structures. The TTT 1 may have pins of various lengths on each leaf 2. By having pins of various lengths on each leaf, preparation of the outer layer (or adventitia) of the tubular tissue structure prior to attachment may be reduced. This may also shorten the time required for the bonding procedure.

[0034] Multiple retainers may allow the tissue structure to attach at multiple points around the tissue structure, which may reduce the stress on each attachment point. Multiple attachment points may also reduce the required strength of the connections to the individual retainers, which may avoid the need for relatively destructive retainers, such as large pins, which can create large holes in the tissue structure and potentially cause significant damage to the tissue structure. Furthermore, multiple attachment points may allow for the use of relatively small, closely spaced retainers, which may be able to simultaneously attach to the tissue structure being compressed. Depending on the nature and size of the tissue structure, the size and type of retainer, and the number of leaves 2, different numbers of retainers may be suitable. For example, thick-walled or relatively inflexible tissue structures may require more retainers per leaf 2, as may large tissue structures. Similarly, if individual retainers are smaller, more retainers may be required. If the TTT1 has a small number of leaves 2, more retainers may be required on each leaf 2. In one example, there are 2 to 10 retainers on each leaf 2. In one embodiment, there are at least eight retainers in total on the TTT 1. In the embodiment of Figure 1A, there are eight retainers in the form of pins 3 on each leaf 2. In this embodiment, there are 32 retainers in total on the TTT 1.

[0035] The retainers may be arranged in one or more rows on each leaf 2. This allows more retainers to be attached to the retention surface 6 of each leaf 2. In the example of FIG. 1A, there are two rows of pins 3 on each leaf 2, an outer row of five pins and an inner row of three pins. To accommodate more retainers on each leaf, the retainers may be spaced closer together, for example, 0.2 mm to 0.5 mm between adjacent retainers.

[0036] Different numbers of leaves may be suitable for different applications. A larger number of leaves may allow for more even distribution of forces on the tissue structure, particularly during any expansion or eversion the tissue structure may undergo. A smaller number of leaves may be easier for the operator to manipulate. The number of leaves may be at least four or at least five. In the example of FIG. 1A, the TTT1 has four leaves 2. In another example, there may be a single leaf instead of multiple leaves 2. In this example, the leaf may be generally cylindrical or frustoconical with a variable circumference. The circumference of such a leaf may change due to deformation, stretching, or rolling and unrolling.

[0037] The leaves 2 may be positioned about a passage 17 through the TTT 1. In use, a tissue structure may be positioned within the passage 17 and held on the leaves 2 about the opening of the passage 17. The passage 17 is sized to accommodate the tissue structure.

[0038] The leaves 2 are flexible to move in a splaying motion. Portions of the leaves 2 can move outward away from the longitudinal axis 19 or inward toward the longitudinal axis 19. In the embodiments of FIGS. 1A, 2A, and 3A, the leaves 2 extend from a ring or base 5. The leaves 2 and ring 5 together form a single, unitary body 10. The distal ends of the leaves 2 can move toward and away from the axis 19 to expand or contract the opening of the passageway 17. This can change the diameter of the opening to aid in the attachment of the tissue structure to the TTT1 or another tissue structure. The outward deflection of the leaves 2 can also be useful for everting the tissue structure, as described in more detail with reference to FIGS. 6 and 7.

[0039] To deflect the leaf 2 inward, the operator can grasp the leaf 2 using, for example, forceps and squeeze the leaf 2. This can reduce the diameter of the opening, making it easier to attach the tissue structure. To aid in this process, the leaf 2 can be provided with features that facilitate grasping. In the example of FIG. 1A, the TTT 1 has a groove 7 formed in the leaf 2 that can receive the end of a forceps and help prevent the forceps from slipping off the TTT 1.

[0040] 1A, different portions of the leaf 2 may be expanded or narrowed, for example, if tissue structure is maintained between the ends of the leaf 2, the leaf 2 may be expanded or narrowed in this portion.

[0041] The leaves 2 may be resiliently flexible throughout the typical range of deflections experienced in use, such that the leaves 2 return to their original configuration after being released.

[0042] In the exploded view of Figure 3A, the body 10, the retainer (in the form of a pin) 3, and the bushing 4 are shown separately. Holes 8 in the leaf 2 are provided to receive the pins 3 in this embodiment. The pins 3 are arranged around a circle, similar to the leaves 2. The bushing 4 is shown in more detail in this view.

[0043] The bushing 4 includes a substantially cylindrical body 13. At the front of the bushing 4 (i.e., the end closest to the distal end of the leaf 2), the bushing 4 is molded into a support surface 11. This support surface 11 is provided to support the outer surface of the tissue structure during use. The support surface 11 may be formed from an enlarged portion of the bushing 4. The enlarged portion may further abut the inner surface of the leaf 2 to urge the leaf 2 outward as the bushing 4 advances from the first rearward position to the second advanced position. The enlarged portion may also engage with the leaf 2 to prevent the bushing 4 from moving back from the advanced position toward the rearward position. For example, the enlarged portion may extend beyond the end of the leaf 2 such that the rear surface of the enlarged portion contacts the end of the leaf 2, thereby preventing it from being pulled back past the leaf 2. Alternatively, the inner surface of the leaf 2 may have a groove or asymmetrical ramp that the enlarged portion engages to prevent it from being pulled back out of the groove or past the steep side of the ramp.

[0044] The support surface 11 may be formed from a flange extending outward from the body 13 of the bushing 4 and at an acute angle, e.g., 90°, relative to the body 13. Alternatively, the support surface 11 may be formed from a "flared" portion curving outward from the body 13. A tubular tissue structure may be supported on this surface with an outward curvature, with the support surface curving outward from the center of the support portion of the tubular tissue structure. The support surface 11 may curve outward from 10° to 120°, or from 30° to 90°. The support surface 11 may curve outward with a radius of curvature selected based on the characteristics of the tissue structure being supported. Some tissue structures may be unacceptably damaged if everted outward too tightly. In such cases, it may be advantageous to select a radius of curvature greater than the value that would cause unacceptable damage to the tissue structure. For example, arteries have relatively thick and inelastic walls compared to other tissue structures, such as veins, and may be unacceptably damaged if everted outward too tightly. In some embodiments, the radius of curvature is greater than 0.2 mm.

[0045] The bushing 4 may further include a flange 12 or other feature to prevent advancement beyond the second advanced position. The flange 12 may abut the rear surface of the ring 5 or another portion of the body 10 to prevent the bushing 4 from moving forward beyond the advanced position. Alternatively, the bushing 4 may include an enlarged portion to form a friction fit with an opening in the body 10 of the TTT1, a bayonet-style fitting to mate with a complementary fitting on the body 10 of the TTT1, or an adhesive to adhere to the body 10 of the TTT1. If the bushing 4 includes an enlarged portion, bayonet-style fitting, or adhesive, this may further act to prevent movement of the bushing 4 from the second position toward the first position in addition to, or instead of, an enlarged portion that forms the support surface 11.

[0046] The bushing 4 may further have a gap 14 within the body 13 to allow for radial expansion of the bushing 4, as will be described in more detail with reference to Figures 17 and 18. Despite the gap 14, the bushing 4 may be substantially circular in cross section. By substantially circular, it is meant that the bushing 4 forms more than 50%, more than 75%, more than 85%, or preferably more than 90% of a complete circle, although it should be noted that the circle referred to may not be a complete circle in actual implementation.

[0047] The bushing 4 can further cause the leaf 2 to deflect. In this embodiment, the bushing 4 is disposed within the passage 17 and configured to move along the passage 17. As shown in FIGS. 1A and 2A, the bushing 4 can be moved between a first rearward position (FIG. 1A) and a second forward position (FIG. 2A). With the bushing 4 in the rearward position, the leaf 2 is not expanded, i.e., the leaf 2 is in the "rest" configuration as shown in FIG. 1A. When the bushing 4 moves to the forward position, the outer edge of the enlarged portion forming the support surface 11 abuts the inner surface of the leaf 2, forcing the leaf 2 into the radially expanded configuration of FIG. 2A and retaining the leaf 2 in that configuration. Alternatively, the bushing 4 can have a portion separate from the enlarged portion forming the support surface 11 that abuts the leaf 2 to expand it and / or retain it in the expanded configuration.

[0048] The bushing 4 may be at least partially plastically deformable, allowing it to deform under the application of force and retain the deformed shape after the force is removed. The bushing 4, or portions thereof, may be formed from a material having appropriate deformation characteristics depending on the application. For example, a material may be selected that undergoes plastic deformation under typical forces applied by an operator during an expansion procedure (described in more detail with reference to FIGS. 17 and 18), yet retains its shape (i.e., is rigid) under typical forces applied by the leaf 2 and retaining portions of tissue structures before and after the expansion procedure. One suitable material would be a metal (e.g., stainless steel or surgical steel, titanium alloy, or cobalt-chromium). Another suitable material would be a polymer, such as a polytetrafluoroethylene / silicone composite.

[0049] Portions of the TTT 1 may be transparent to allow the operator to view tissue structures during use, in particular the bushing 4 and / or one or more of the leaves 2 may be transparent.

[0050] In one embodiment, a suction port may be provided in the TTT 1. The suction port may form a retainer alone or in combination with the pin 3. In one embodiment, the suction port is provided at the end of the pin 3.

[0051] Figure 4 shows an embodiment in which the retainers are pins 3 with suction ports 29 at their ends. The suction ports 29 are connected to a low pressure source via suction lines 9. In the embodiment of Figure 4, the suction lines 9 pass through each pin 3 and leaf 2 and connect to the low pressure source in the region of the ring 5. The low pressure source in this embodiment is a syringe 28, which creates a partial vacuum in the suction line 9 when its plunger is retracted. Alternatively, the low pressure source could be a vacuum pump or the like.

[0052] 5-7 show the TTT1 in use with a tubular tissue structure 16 in various states.

[0053] In Figure 5, tissue structure 16 is positioned within the passageway. In this embodiment, the tissue structure has been cut so that a portion 18 near the cut end extends out of passageway 17 and into the area of the retainer (in this embodiment, pin 3). In this state, bushing 4 is not advanced and leaf 2 is in a rest position.

[0054] In Figure 6, tissue structure 16 is attached at portion 18 to retainer 3. As can be seen in Figure 6, portion 18 is attached to retainer 3 at many points arranged in a generally circular pattern and is held on device 1. In this state, bushing 4 is not advanced and leaf 2 is in a rest position. In this position, portion 18 of tissue structure 16 is not fully everted. Depending on the range of motion of leaf 2 and the angle at which leaf 2 is attached to tissue structure 16 in the retracted configuration, portion 18 of tissue structure 16 may be partially everted or not everted at all.

[0055] In Figure 7, the bushing 4 has been advanced to an advanced position. The leaves 2 have been expanded outward, causing the portion 18 of the tissue structure 16 to evert more than in the configurations of Figures 5 and 6. The portion 18 of the tissue structure 16 may be everted outward up to, about, or more than 90° and need not be completely "inside out." In one embodiment, the portion 18 of the tissue structure 16 is everted outward about 90°. A 90° eversion may be optimal in some circumstances to present a large area of the interior surface of the tubular tissue structure 16 for coupling to another tubular tissue structure without everting the tissue structure 16 outward more than necessary.

[0056] Although not shown in FIG. 7 , the support surface of bushing 4 is positioned near the end of leaf 2. In this position, the support surface of bushing 4 contacts and supports the outer surface of everting portion 18 of tissue structure 16 to form a broad, substantially circular surface suitable for apposition with another tissue structure to form an anastomosis. The end of leaf 2 may also form a support surface for the everting portion of the tissue structure in this state. In this embodiment, support surface 6 of leaf 2 is positioned near and at a small angle relative to support surface 11 of bushing 4, such that leaf 2 and bushing 4 cooperate to form a composite support surface. In this configuration, support surface 6 of leaf 2 may be at an angle of less than 45°, less than 30°, or less than 15° relative to the support surface of bushing 4. In alternative embodiments, leaf 2 may form the entire support surface without the contribution of bushing 4.

[0057] As shown in FIG. 3A , the support surface 11 of the bushing 4 covers substantially the entire circle, with only small gaps 14. Even when expanded, these gaps are smaller than the spacing 15 between adjacent leaves 2, allowing for a larger support surface than the support surface 6 of the leaf 2 alone would provide. In this way, the support surface 11 of the bushing helps ensure a large, uniformly supported surface around substantially the entire circumference of the everted portion 18. By substantially the entire circumference, we mean more than 50%, more than 75%, more than 85%, or preferably more than 90% of the circumference. This can help to form a good seal between the two tissue structures when they are joined to form an anastomosis. The outward curvature of the support surface 11 of the bushing 4 away from the center of the everted portion supports the everted portion 18 of the tissue structure 16 to similarly curve outward. The everted portion 18 is supported in this shape by the support surface 11 in contact with its outer surface. As previously mentioned, this can help to avoid damage to the tissue structure 16.

[0058] Figure 8A shows a system 20 for joining tubular tissue structures, including a first TTT1, a second TTT1', a first joining device 21, and a second joining device 22. Figure 9A is an exploded view of the system, showing the first joining device, the second joining device, the first TTT1, and the second TTT1' separately. Figure 9B is an exploded view of an alternative system. Figure 10 shows the first joining device 21 and the first TTT1 in more detail.

[0059] The first TTT1 and second TTT1' may be the TTTs described with reference to Figures 1A, 2A, 3A and 4-7, or may be different TTTs. TTT1, TTT1' each hold a portion of a tubular tissue structure at at least one respective holding location 27 around the tissue structure. In one embodiment, TTT1, TTT1' each hold the tissue structure at two or more holding locations 27. In the embodiment of Figure 8, TTT1', TTT1a each have four leaves 2, each leaf 2 having a holding location 27 corresponding to the area covered by multiple pins 3, 3'.

[0060] The first and second coupling devices 21 and 22 can be butted together to juxtapose and couple the everted portions of the tissue structures, joining the tissue structures. The coupling devices 21 and 22 ensure that the retention positions 27 and 27' of the retaining devices are offset from one another when coupled. This can help ensure a good, uniform seal around the bond interface by "filling" the gap between the retention positions of one TTT and the other. This can also prevent or reduce the possibility of the retainers of one device clashing with the retainers of the other device. For example, if the retainers are pins, the offset prevents the pins of the TTT from contacting each other. Contact between the pins could prevent the retained portions of the tissue structures from joining together sufficiently to form a good seal.

[0061] The coupling devices 21, 22 include alignment features that ensure they couple in only one of a discrete set of relative orientations about the longitudinal axis 25. In one example, the alignment features are one or more pins and one or more holes for receiving the pins. The pins may be provided on both or only one of the coupling devices. Correspondingly, holes may be provided on both or only one of the coupling devices. In the example of FIGS. 8A, 9A, and 9B, the first coupling device 21 has two pins 23 and the second coupling device 22 has two holes 24. The pins 23 in this example are not equally spaced about the longitudinal axis 25; i.e., the rotational offset between the pins is not 360° / n, where n is the number of pins. This limits the coupling devices 21, 22 to being able to couple in only one relative orientation about the longitudinal axis 25. The pins 23 may have features such as teeth or barbs to engage with the second coupling device 22 around the holes 24. An adhesive may be provided on the pin 23 or the hole 24. The pin 23 or the hole 24 may be tapered to form a friction fit. In one embodiment, the hole 24 is tapered to engage with a pin 23 having a constant cross-section.

[0062] Each coupling device further includes one or more alignment features to ensure that each TTT1 is retained in one of a discrete set of relative orientations about the longitudinal axis 25. That is, a TTT cannot be retained in the coupling device at any angle, but only at an angle that ensures its retainer is offset from the retainers of the other TTTs. This allows the coupling device and each TTT1 to mate in one or more predetermined, compatible orientations about the axis 25. Each coupling device may have a recess 26, 26' that receives the respective TTT1, TTT1'. In one embodiment, the inner surface of the recess 26, 26' may be noncircular, and a portion of the outer surface of each TTT1, TTT1' may also be noncircular. The noncircular shape of the device may prevent the device from rotating out of a specific relative orientation when the TTT1, TTT1' is received in the recess 26, 26'. In the embodiment of FIG. 9B, the recesses 26, 26' and the TTT1, TTT1' are polygonal. Additionally or alternatively, other mating structures may be provided to prevent rotation of TTT1, TTT1' out of a particular relative orientation with respect to the coupling devices 21, 22. For example, these may include holes for receiving pins from one device and pins from the other device, raised portions from one device, and grooves for receiving raised portions from the other device. If such mating structures are provided, the outer portions of the recesses 26, 26' and TTT1, TTT1' may be circular. In the embodiment of FIGS. 8 and 9A, the recesses 26, 26' are generally circular in cross section, although in this embodiment they do not form a complete circle. More specifically, each recess is approximately three-quarters circular in cross section.

[0063] In the embodiments of FIGS. 8A and 9A, the coupling devices 21, 22 are generally circular in cross section, but do not form a complete circle. In this embodiment, the coupling devices 21, 22 are approximately three-quarters circular. This means that the coupling devices 21, 22 are each open on one side. This allows the coupling devices 21, 22 to be moved from their sides over the tubular tissue structure and position the tissue structure within the central opening of the coupling devices 21, 22. This may be quicker and easier than inserting the cut end of the tissue structure longitudinally through a complete circular opening. The opening may also allow the operator to view the interface between TTT1, TTT1′, and the tissue structure while coupling the tissue structures.

[0064] 10 shows the first coupling device 21 with the first TTT 1 positioned within the recess. The first TTT 1 has a tubular tissue structure 16 held at four holding locations 27 around the holding portion 18.

[0065] 11 illustrates a system used to connect a first tubular tissue structure 16 and a second tubular tissue structure 16' together. The retention location 27 of the first TTT 1 is shown offset from the retention location 27' of the second TTT 1'. The pin 23 of the first connecting device 21 is shown inserted into the hole 24 of the second connecting device 22. In this configuration, the system 20 forms a connection or anastomosis between the two tubular tissue structures 16, 16'.

[0066] An alternative embodiment is shown in Figures 1B, 2B, 3B, 8B, and 9C. In this case, the TTT device 1 has five leaves 2. As shown in Figure 3B, each leaf 2 has a recess 100 that receives a hook insert 102. Each hook insert 102 has multiple retainers / hooks 3 to which a tubular structure can be attached, similar to the pins 3 in Figure 1A. This embodiment may facilitate easier device manufacture and assembly and improve the vessel retention process. The hook inserts 102 may be made of a hard material, such as stainless steel, with sharp hooks 3 machined using wire EDM. The sharp, hard hooks 3 easily and atraumatically puncture the arterial wall. The base 106 of the hook insert 102 forms a smooth surface that the bushing contacts as it advances through the TTT, deflecting the leaves radially outward. However, the leaves 2 into which the hook inserts 102 are inserted must remain deformable so that the leaves 2 can flex radially outward as the bushings 4 are advanced, everting the vessel. To accomplish all this, the hook inserts 102 are most easily manufactured as separate components that can be inserted retrogradely into the recesses 100. That is, these recesses 100 can function similarly to the holes 8 that receive the pins 3 in FIG. 3A.

[0067] The hooks 3 may include three hooks per hook insert. There may be one inner hook and two outer hooks. Each hook may be tapered and / or curved outward. The length of each hook may be 0.5 mm to 2.0 mm. The thickness of each hook may be 0.05 mm to 1.00 mm, for example, 0.15 mm.

[0068] The hook insert 102 may be held in place by using an interference fit type mechanism. Alternatively, the hook insert 102 may have a lip on the rear end that snaps into place within the recess 100. In another alternative embodiment, a low viscosity adhesive may be used to bond between the hook insert 102 and the recess 100. Combinations of all of the above may also be utilized.

[0069] The hook insert 102 has a lip 104 on its outer surface to prevent the forceps from disengaging from the leaf. The forceps are used to properly position the TTT 1 over the vessel it is intended to hold. When a soft, tubular tissue structure, such as an artery, is attached to the hooks 3 of the TTT, the user can use fine forceps to lift the vessel and attach it to the hooks 3. To aid in vessel retention and minimize vessel distortion during this process, the user can apply a compressive force with the forceps to deflect the leaf 2 radially inward, bringing the hooks 3 closer to the vessel wall. When a compressive force is applied, the lip 104 prevents the forceps from unintentionally disengaging from the leading edge and damaging the soft tissue structure. This lip serves the same function as the groove 7 in FIG. 1A. The lip height can be approximately 0.2 mm to 1.0 mm.

[0070] In this particular five-leaf configuration, the operator grasps the leaves from the side of the TTT with one clamp tip against the top leaf and the other clamp tip against the bottom two leaves. The top leaf is the leaf that bends most inward, and the operator attaches the artery to its hooks first. The operator rotates the TTT, compressing each leaf in turn as the artery attaches to the retainer on each leaf.

[0071] The base 106 of the hook insert 102 extends slightly radially inward beyond its respective leaf 2, and therefore it is the base 106 that contacts the bushing 4. This surface creates a smoother interface as the bushing 4 advances to radially expand the leaf. As noted above, the hook insert can be a rigid material such as stainless steel, titanium, or hard plastic. Rigidity in this context refers to the ability to respond to the forces generated by forcing the bushing 4 into its final position.

[0072] The leaves 2 may be molded from a deformable plastic. The plastic and stiffness of each leaf structure may be designed so that the leaf angle (relative to the longitudinal axis 19) changes by 2° to 15°, or approximately 9°, as the bushing 4 advances. Deformable in this context refers to the property of responding to the forces exerted by forcing the bushing 4 into its final position.

[0073] As shown in FIG. 9C, this embodiment of coupling device 21 features recesses 26 that receive coupling flanges or wings 108 on either side of the TTT1, and a lip 110 on the front clip 112 of coupling device 21 that prevents TTT1 from slipping out of recesses 26. TTT1 and TTT1' are attached to each end of the everted vessel and sandwiched between the respective coupling devices 21, 21'. The two coupling devices 21, 21' are then brought into proximity, rotationally offset (so that their respective leaves and hooks interlock in the spaces between the opposing leaves), and then permanently coupled by pin 23. Alternatively, each TTT can include coupling holes 24, 24', and the coupling pin 23 can directly engage the respective TTT1, TTT1'.

[0074] This type of coupling device 21 may improve visibility of the recess 26 into which the TTT1 must fit. The coupling wings 108 allow the TTT1 to be inserted from above (or conversely, the coupling device 21 can be introduced from below), thereby reducing the total amount of movement required to mate the TTT1 with its corresponding coupling device 21. Mating may be achieved using an interference fit or a snap lock with a deformable front clip 112.

[0075] The front clips 112 secure the tie wings 108 in place and prevent forward movement, meaning that the TTT1 cannot slide out of the tie wings or tilt away from the central axis 25.

[0076] This approach can also reduce the overall length of the coupler (i.e., when the coupler is connected by pin 23) because there is no longer a central gap that the TTT must first pass through before retrograde translation to fit into recess 26 as shown in FIG. 9A.

[0077] Various methods will now be described with reference to Figures 12 to 21. These methods may be performed individually as separate procedures or may be performed together as part of a single procedure.

[0078] In Figure 12, a portion 18 of the tubular tissue structure 16 is inserted into the passage of the TTT1 in the direction indicated by arrow 33. In this embodiment, the inserted portion 18 is the cut end of the tissue structure 16. The TTT1 in this embodiment is the TTT described with reference to Figures 1-8. In such an embodiment, the portion 18 of the tissue structure 16 is threaded through the bushing 4 and between the leaves 2.

[0079] In FIG. 13 , the attachment tool 30 is in contact with the portion 18 of the tissue structure 16 at position 30′. The attachment tool 30 may include a portion, such as a tip 31, that is inserted into the opening of the tubular tissue structure 16. The attachment tool 30 has a deformable surface 32 that allows the portion 18 of the tissue structure 16 to be pressed against multiple retainers simultaneously. Before or while pressing the portion 18 of the tissue structure 16 against the retainers, the operator may squeeze or otherwise contract the leaves 2 inward to bring the ends of the leaves 2 closer together. This facilitates attachment of the tissue structure to the TTT 1, particularly in the case of narrow or relatively inflexible tissue structures. In one example, the operator grasps the TTT 1 in the groove 7 with forceps and squeezes to contract the leaves 2.

[0080] 14, tool 30 is in position 30', with deformable surface 32 deformed from the state shown in FIG. 13 to better contact portion 18 of tissue structure 16 and press it against the retainer. Tool 30 may also be rotated, as shown by arrow 36, to aid in circumferential attachment of portion 18 of tissue structure 16.

[0081] Pressing portion 18 against the retainers simultaneously attaches portion 18 to the retainers at multiple locations, each location corresponding to one of the retainers. This eliminates the need to attach the tissue structures to the retainers one by one. As indicated by arrow 37, the tissue structure is everted somewhat outward on the retainers to attach it to the retainers.

[0082] Tool 30 may contain a fluid, such as air, water, or gel, enclosed by deformable surface 32. In one embodiment, the fluid-filled region may be squeezed or otherwise compressed by an operator in one area to cause expansion of the tool in the area in contact with the tissue structure. This can gently compress the tissue structure around all or most of its circumference, helping to rapidly attach many retainers simultaneously. Deformable surface 32 may be an elastically flexible surface.

[0083] In an alternative embodiment, the operator can press against the tissue structure without the aid of tool 30, for example with a finger.

[0084] In the embodiment shown in Figures 12-14, the retaining portion 18 of the tissue structure 16 is the portion near the cut end of the tissue structure. In an alternative embodiment, the retaining portion may be the area around the slit on the side of the tissue structure. This may allow the TTT1 to be used as a side coupler for end-to-side joining of tubular tissue structures.

[0085] In Figure 15, tissue structure 16 is attached to TTT 1 at portion 18. Bushing 4 is in a first rearward position and leaves 2 are in a retracted configuration. By pushing bushing 4 in the direction indicated by arrow 38, the operator can advance bushing 4 toward a second, advanced position shown in Figure 16.

[0086] In FIG. 16 , the bushing 4 is in an advanced position, with the ends of the leaves 2 expanding radially outward, as indicated by arrows 39. This expansion everts a portion 18 of the tissue structure 16. The everting portion 18 is supported in an everted state by the support surface 11 of the bushing 4. The bushing 4 maintains the everting portion 18 in an outwardly curved configuration by contacting the outer surface of the everting portion 18 with the curved support surface 11. Thus, the TTT 1 can quickly and easily evert a portion of the tissue structure by advancing the bushing 4.

[0087] The radius of curvature of the everting portion may be greater than that which would damage tissue structures. The radius of curvature may be greater than 0.2 mm.

[0088] In alternative embodiments, the TTT1 may include other mechanisms for expanding the leaves 2 and everting the portions 18. For example, the TTT1 may include an outer ring connected to the leaves that slides back to pull the leaves outward and is then locked into place. In another alternative embodiment, the TTT1 may only hold the tissue structure, and a separate device may be used to evert the tissue structure. In yet another embodiment, the tissue structure may be everted by the expansion process of FIGS. 17 and 18 below.

[0089] 17 and 18 show a tool for expanding a portion of a tubular tissue structure. This can be useful when the tissue structure has a smaller diameter than the diameter of the tissue structure to be joined. As shown in FIG. 17, a portion 18 of tissue structure 16 is held around opening 17 of TTT1. Initially, this portion has a first diameter. An expansion tool 40 is used to expand opening 17, which also expands the held portion 18 of tissue structure 16 to have a second diameter. In the example of FIGS. 17 and 18, tapered portion 41 of expansion tool 40 is inserted into opening 17 in the direction indicated by arrow 43. Tool 40 can be grasped by an operator by grip 42.

[0090] Insertion of the tapered portion 41 forces the plastically deformable portion of the bushing 4 radially outward, as shown by arrows 44 in FIG. 18. This forces the leaves 2 of the TTT1 outward. The bushing 4 can then hold this shape against the inward force of the leaves and tissue structures to hold the tissue structure in its expanded state. The tissue structure can be expanded to more closely match the width of another tissue structure to which it is attached. This can aid in joining the tissue structures. If the tissue structures to be joined have different diameters, the tissue structure with the smaller diameter can be expanded. If the tissue structures have similar diameters, no expansion process is necessary.

[0091] Alternatively, a different dilating tool having an expandable portion may be used to dilate the opening. Instead of a tapered portion, the opening may be dilated by inserting the expandable portion into the opening and expanding it. In one embodiment, the tool contains a fluid encapsulated by a deformable surface that can expand when the fluid is compressed in another region of the tool. As described above, dilating the opening may be used to evert a portion of the tissue structure by deflecting leaves outward, thereby everting the retaining portion 18 of the tissue structure outward.

[0092] In Figures 19-21, TTT1 and TTT1' are engaged with coupling devices 21, 22 and tissue structures 16, 16' are coupled using the coupling devices to form an anastomosis.

[0093] In Figure 19, coupling devices 21, 22 are passed laterally through tissue structures 16, 16' while everting portions of tissue structures 16, 16' are held on TTT1, TTT1'. Coupling devices 21, 22 are then moved toward their respective TTT1, TTT1' in the direction indicated by arrows 45, 45'. This engages coupling devices 21, 22 with TTT1, TTT1', as shown in Figure 20.

[0094] In Figure 20, TTT1, TTT1' are engaged with their respective coupling devices 21, 22. In this embodiment, TTT1, TTT1' are positioned within coupling devices 21, 22 at a predetermined relative angle about the longitudinal axis, as described in detail with reference to Figure 8. Coupling devices 21, 22, along with TTT1, TTT1', are then moved toward each other in the direction indicated by arrows 45, 45' to engage each other and bring the everted portions of tissue structures 16, 16' into contact with each other.

[0095] 21, coupling devices 21, 22 are coupled to one another by pin 23 and hole 24. The everted portions of tissue structures 16, 16' are also coupled to one another at interface 50 by being held to one another by coupling devices 21, 22 without the need for sutures or staples.

[0096] As described in detail with reference to Figure 8, the TTTs 21, 22 are abutted with a predetermined rotational offset between the retainers of the TTTs. As described in detail with reference to Figure 3, the abutting everted portions are supported around substantially their entire periphery. These features may ensure a good seal around the interface 50 and minimal leakage of fluid.

[0097] After joining the devices 21, 22 and tissue structures 16, 16′, the operator may observe the newly formed anastomosis for leaks or other signs of insufficient joining. If these are noticed, the operator may separate the devices 21, 22 by pulling them apart without removing the sutures or staples. This may be a non-destructive process, such that the devices 21, 22 may be reunited after separation (and any other corrective measures, such as reattachment, taken) without detaching the TTT1, TTT1′ from the tissue structures 16, 16′ or cutting the retaining portions of the tissue structures 16, 16′.

[0098] The described devices, systems, and methods may enable fast, safe, and easy attachment of tissue structures to tubular tissue deformers, eversion of tissue structures, expansion of tissue structures, and joining of tissue structures with reduced risk of damage to the tissue structures, which may be particularly suitable for joining arteries.

[0099] While the invention has been illustrated by the description of its embodiments and the embodiments have been described in detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such details. Additional advantages and modifications will be readily apparent to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant's general inventive concept.

Claims

[Claim 1] 1. A system for joining tubular tissue structures, said system comprising: a first tubular tissue deformer (TTT) having one or more first retainers configured to hold a first portion of a first tubular tissue structure, the one or more first retainers configured to be positioned at one or more first retainer positions about the first retained portion of the first tubular tissue structure; a second tubular tissue deformer (TTT) having one or more second retainers configured to hold a second portion of a second tubular tissue structure, the one or more second retainers configured to be positioned at one or more second retainer positions about the second retained portion of the tubular tissue structure; a coupling mechanism configured to couple first and second retaining portions of the first and second tubular tissue structures and to maintain a predetermined rotational offset between the one or more first retainer positions and the one or more second retainer positions in use, the rotational offset being an offset about a longitudinal axis passing through the first and second TTTs when the retaining portions are coupled in use; and A system comprising:

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