Patent Application
20150088172
The present invention relates to a vascular anastomosis device, which is a device for connecting and conglutinating two blood vessels with different diameters.
Conventionally, for connecting and conglutinating two blood vessels, suturing or anastomosis using an anastomosis device has been performed. In the cases where the two blood vessels have different diameters, however, the only option is suturing. For anastomosis of blood vessels with different diameters, it is necessary that the two end surfaces to be coupled be made identical in size. For the purpose, as shown in
To overcome the disadvantage, an anastomosis device for anastomosing blood vessels by separately inserting blood vessels through truly circular rings with pins, pulling outward the end portion of each vessel and impaling it on the pins, and joining the two rings together was developed (refer to Non Patent Literature 1). Referring to
In the cases where blood vessels with almost the same diameters are subjected to anastomosis, the anastomosis device shown in
The present invention was made in view of such a problem of the prior art, and an objective thereof is to provide a vascular anastomosis device and a vascular anastomosis method which enable favorable anastomosis of blood vessels with different diameters.
To solve the above problem, the present invention utilizes the suturing shown in
First, as shown in
That is, the vascular anastomosis device of the present invention is a vascular anastomosis device for anastomosing two blood vessels with different diameters, characterized in that the device comprises a first ring with pins and a second ring with pins both made of a material which is deformable by an external force and allows the pins to stick thereinto, and an openable ring holder, which is made of a pair of components, detachably holds the first ring and the second ring, and has a means for deforming the rings with pins, and that vascular anastomosis can be achieved in the following manner: the ring holder holding the rings is opened, the end portion of the large-diameter blood vessel is inserted through the first ring and the vascular wall is extended outward 90 degrees and impaled on the pins, the end portion of the small-diameter blood vessel is inserted through the second ring, an incision is made in a longitudinal direction from the end surface of the small-diameter blood vessel, the first ring and the second ring are deformed into a same elliptical shape by the means for deforming the rings so that the minor axis agrees with the diameter of the small-diameter blood vessel, the small-diameter blood vessel is elliptically opened and the vascular wall is extended outward 90 degrees and impaled on the pins, and the first ring and the second ring are joined together to allow the pins provided on the ring in one component to stick into the ring in the other component and anastomose the large-diameter blood vessel and the small diameter blood vessel.
In addition, the vascular anastomosis method of the present invention is a vascular anastomosis method for anastomosing two blood vessels with different diameters, characterized in that a first ring with pins and a second ring with pins both made of a material which is deformable by an external force and allows the pins to stick thereinto are provided, and that the end portion of the large-diameter blood vessel is inserted through the first ring and the vascular wall is extended outward 90 degrees and impaled on the pins, the end portion of the small-diameter blood vessel is inserted through the second ring, an incision is made in a longitudinal direction from the end surface of the small-diameter blood vessel, the first ring and the second ring are deformed into a same elliptical shape by a means for deforming the rings so that the minor axis agrees with the diameter of the small-diameter blood vessel, the small-diameter blood vessel is elliptically opened and the vascular wall is extended outward 90 degrees and impaled on the pins, and the first ring and the second ring are joined together to allow the pins provided on the ring in one component to stick into the ring in the other component and anastomose the large-diameter blood vessel and the small diameter blood vessel.
By using the vascular anastomosis device and the vascular anastomosis method of the present invention, blood vessels with different diameters can be anastomosed. Since the rings with pins are made of a material which is deformable by an external force and allows the pins to stick thereinto, vascular obstruction due to collapse can be prevented and flexible expansion can be achieved when blood flow is increased.
Hereinafter, embodiments of the present invention will be described. Needless to say, other embodiments can also be used without departing from the scope of the invention.
The ring before deformation may be truly circular or elliptical, and needs to be flexible. When two blood vessels with different diameters are anastomosed, the diameter of the rings needs to fit the larger blood vessel. If the diameter of the rings is smaller than that of the larger blood vessel, anastomosis will be impossible due to too loose fitting for the large-diameter blood vessel. Conversely, if the diameter of the rings is too large, the small-diameter blood vessel needs to be forcibly adapted to the large ring, which can result in wall tearing of the small-diameter blood vessel. As mentioned above, the rings are deformed into an elliptical shape. As will be described later in the section of Deformation Mechanism, there is a possibility that efficient joining of the two rings cannot be achieved due to ring slippage that can occur while a predetermined force for elliptical deformation is transmitted to the ring. For efficient force transmission to both sides of each ring, and for the prevention of slippage or falling of the ring during the deformation, it is recommended that the flat surface 74 perpendicular to the direction of the force is provided on the outer side surface of the ring, as shown in
Next, the dimension of the rings will be described. The dimension and the shape of the rings used in the present invention are not particularly limited and a ring of any size and shape may be used as long as vascular anastomosis can be efficiently achieved using the rings. However, since blood vessels with different diameters are anastomosed in the present invention, the rings need to have a flange-like shape and a diameter which fits the large-diameter blood vessel, as described above. In this view, commercially available standard rings can be used, but other rings than those in the standard range are also usable in principle. It is recommended that, in the cases where elliptical rings are used, the rings have such a diameter that the long-diameter blood vessel can effortlessly be inserted therethrough. In particular, regarding commercially available ordinary rings for anastomosing blood vessels of the same diameter, those having inner diameters of 1.0 to 3.0 mm are widely used, and in the present invention as well, the inner diameter (in the case of an ellipse, the inner shorter diameter; hereinafter referred to as the “inner minor axis”) may be suitably used as described above. However, the vascular anastomosis device of the present invention can also be applied to larger blood vessels, for example the human aorta, of which the diameter is 40 mm or more. Too fine blood vessels (for example, capillaries) cannot be anastomosed or do not need anastomosis in principle. Therefore, the range of the ring inner diameter (in the case of an elliptic ring, the inner minor axis) of 0.3 to 50 mm is sufficient for most human blood vessels. When applied to the anastomosis of blood vessels of large animals, further larger inner diameters may be used. The width of the ring flange (half of the difference between the outer diameter and the inner diameter) is also not particularly limited, and any ring having a similar flange width to that of a commercially available conventional ring can be used without any problem. However, it is recommended that the flange width is determined as appropriate depending on the diameter of the blood vessel to be inserted and the shape of the pins. Specifically, the generally recommended flange width of the ring is about 0.3 to 10 mm.
Further, the thickness of the rings used in the present invention is not particularly limited and has only to allow the pins provided on one ring to stick into the other ring when the rings are joined and to prevent the pins from being easily pulled out. Specifically, when applied to human blood vessels as described above, the recommended thickness is 0.3 to 20 mm, in particular 0.5 to 10 mm. When applied to blood vessels with larger diameters, for example to blood vessels of large animals, the thickness may be more.
As will be described later, the ring body of the present invention made of a flexible material may be thicker and the pins may be longer, as compared to conventional commercial rings and pins, to some degree in order that pins are more securely caught in the opposing ring in the joined state of the rings. Too long pins will stick through the opposing ring and protrude from the other side, causing problems. Too small dimensions (including the thickness) of the rings can prevent efficient vascular anastomosis and too large dimensions can cause adverse effects on the patient after operation.
The rings generally used for conventional anastomosis devices are made of polyethylene resins, which are not flexible. Materials that can be used for the rings of the present invention are deformable by an external force and allow the pins to stick thereinto, and as such materials, flexible materials can be used. The materials preferably have biocompatibility as well. Specific examples of the materials that can be used for the rings of the present invention include a silicone resin, a natural rubber, a synthetic rubber, a flexible epoxy resin, a thermoplastic elastomer, an aliphatic polyurethane, a polyether block amide copolymer, and a flexible fluororesin. However, materials usable in the present invention are not limited to these. It is preferable that the ring made of such a flexible material easily deforms when a predetermined force is applied, and it is more preferable that the ring can be restored to the original shape when the force for deformation is removed. The reason is that, in the course of anastomosis of blood vessels with different diameters, even if the force for deformation is so strong that the ring deforms into an unfavorable shape, removal of the force restores the ring to the original shape, allowing another deformation.
A locking hook (not shown) provided on the cylinder 23 is engaged in the slot 27 of the cap 26, and thereby the cartridge at the tip of the vascular anastomosis device is protected with the cap 26, as shown in
As shown in
The diameter of the rings 31 fits the large-diameter blood vessel. The large-diameter blood vessel is inserted through either of the right and left rings 31 and the vascular wall is impaled on the pins of the ring, as shown in
The shaft as the rotation center of the cartridge is, as shown in
Next, the small-diameter blood vessel is inserted through the other ring 31, and the tip of the driver 39 is rotated in an engaged state with the protrusion 40 to move the threaded portion 38 in the upward direction in the figure. As a result, the movable retainer plate 33 is subjected to a force in the direction toward the fixed retainer plate 35 due to the resilience of the spring 34, and the ring 31 is deformed into an elliptical shape. The driver 39 is continuously moved until the minor axis of the deformed rings 31 corresponds to the diameter of the small-diameter blood vessel. Since the deformation of the rings 31 by the operation of the driver 39 occurs in the same manner in both the right and left cartridge components, the two rings 31 are deformed into the same elliptical shape. Then, an incision is made in a longitudinal direction from the end surface of the small-diameter blood vessel, the small-diameter blood vessel is elliptically opened, and the vascular wall is extended outward 90 degrees and impaled on the pins (refer to
The right and left cartridge components 28a and 28b are joined to allow the pins provided on the ring in one component to stick into the ring in the other component. Thus, the vascular anastomosis is completed (refer to
As described above, the cartridge at the tip of the vascular anastomosis device is protected with a cap, which is to be removed in the same manner as above.
As shown in
The diameter of the rings 44 fits the large-diameter blood vessel. The large-diameter blood vessel is inserted through either of the right and left rings 44 and the vascular wall is impaled on the pins of the ring, as shown in
Next, the small-diameter blood vessel is inserted through the other ring 44, and the movable retainer plate 47 is pressed by the thread 46. As a result, a force in the direction from the movable retainer plate 47 toward the fixed retainer plate 49 against the resilience of the spring 48 generates, and allows the ring 44 to be deformed into an elliptical shape. The thread 46 is screwed until the minor axis of the deformed rings 44 corresponds to the diameter of the small-diameter blood vessel. Then, an incision is made in a longitudinal direction from the end surface of the small-diameter blood vessel, the small-diameter blood vessel is elliptically opened, and the vascular wall is extended outward 90 degrees and impaled on the pins (refer to
The ring 44 through which the large-diameter blood vessel is inserted is pressed by screwing the thread 46 to the same degree as above, and thereby the two rings are deformed into the same elliptical shape. In this example, in order to equalize the deformation amounts of the two rings, it is recommended that scale marks be provided on the outer frame 45 so that the amount of pushed-in of the thread (or the amount of movement of the movable retainer plate 47) could be checked.
The right and left cartridge components 41a and 41b are joined to allow the pins provided on the ring in one component to stick into the ring in the other component. Thus, the vascular anastomosis is completed (refer to
Here, the means for moving the movable retainer plate in Example 1 is replaced by bevel gears.
As described above, the cartridge at the tip of the vascular anastomosis device is housed in a cap, which is to be removed in the same manner as above.
As shown in
The shaft as the rotation center of the cartridge is, as shown in
When the operation shaft 55 at the end of the rotatable driver 54 is operated to rotate the bevel gear 52, the bevel gear 56 meshing with the bevel gear 52 rotates and tries to send the rod 57 to the right, but the frame 60 prevents the movement. The counteraction forcibly sends the movable retainer plate 59 meshing with the threaded portion 58 of the rod 57 to the left. Since the threaded portion 58 of the rod 57 protruded from the bevel gear 56 meshes with the movable retainer plate 59, rotation of the bevel gear 56 could horizontally rotate the movable retainer plate 59. The stoppers 62, however, prevent the horizontal rotation. Thus, the counteraction resulting from the prevention of the movement of the rod 57 to the right, that is, the movement of the movable retainer plate 59 to the left exerts a force on the ring 64 held by the ring holder 63 in the cartridge component 50a in the direction toward the fixed retainer plate 61. The rod 57 is provided with the guide member 65. There is no intention to provide detailed description, but the other cartridge component 50b has the same configuration, that is, comprises the ring holder 63, the ring with pins 64, the bevel gear 56, the rod 57, the movable retainer plate 59, the outer frame 60, the fixed retainer plate 61, stoppers 62, and the guide member 65. In this example, the right and left movable retainer plates can move simultaneously and by the same amount.
The diameter of the rings 64 fits the large-diameter blood vessel. The large-diameter blood vessel is inserted through either of the right and left rings 64 and the vascular wall is impaled on the pins of the ring, as shown in
After the small-diameter blood vessel is inserted through the other ring 64, the operation shaft 55 at the end of the rotatable driver 54 is operated to rotate the bevel gear 52. The bevel gear 56 meshing with the bevel gear 52 rotates and tries to send the rod 57 to the right, but the frame 60 prevents the movement. As the counteraction, the movement of the movable retainer plate 59 meshing with the threaded portion 58 of the rod 57 to the left exerts a force on the ring 64 held by the ring holder 63 in the cartridge component 50a in the direction toward the fixed retainer plate 61. Consequently, the ring 64 is deformed into an elliptical shape. The operation shaft 55 is operated until the minor axis of the deformed rings 64 corresponds to the diameter of the small-diameter blood vessel. Since the deformation of the rings 64 by the operation of the operation shaft 55 occurs in the same manner in both the right and left cartridge components, the two rings 64 are deformed into the same elliptical shape. Then, an incision is made in a longitudinal direction from the end surface of the small-diameter blood vessel, the small-diameter blood vessel is elliptically opened, and the vascular wall is extended outward 90 degrees and impaled on the pins (refer to
The right and left cartridge components 50a and 50b are joined to allow the pins provided on the ring in one component to stick into the ring in the other component. Thus, the vascular anastomosis is completed (refer to
In Example 4, in order to reduce the friction at the contact site between the rod 57 and the outer frame 60 in Example 3, a ball bearing 66 is attached to the contact site between the rod 57 and the outer frame 60, as shown in
In the cases where the rings with pins are made of a flexible material, the pin 67 having a conventional shape as shown in
In a preferable example, the pins and the inner portion of the ring are made of a hard material (for example, polyethylene), and the outer portion and other portions of the ring are made of a flexible material (see, for example, paragraph [0017]). In a recommendable example, as shown in
Further, for the prevention of slippage or falling of the ring during deformation, the outer side surface of the ring may be processed to have one or more appropriate flat surfaces.
The present invention is useful as a device for connecting and conglutinating two blood vessels with different diameters.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-016272 | Jan 2012 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2013/051258 | 1/23/2013 | WO | 00 |
