JP7774561B2 - Blood vessel model and evaluation method for long medical object - Google Patents

Description

The present invention relates to a vascular model that simulates a blood vessel and a method for evaluating a medical elongated object using the vascular model.

In recent years, interventions have been performed in which long medical objects such as catheters and guidewires are inserted through the skin into blood vessels and passed through the blood vessels to reach the desired location. Because interventions are performed through complexly curved blood vessels, the catheter must be able to reach the desired location. For this reason, Patent Document 1, for example, describes a blood vessel model used to test the operability of long medical objects.

Japanese Patent Application Laid-Open No. 2017-003637

When performing prostatic arterial embolization as a treatment for benign prostatic hyperplasia or hepatic arterial embolization as a treatment for liver cancer, selecting a small branch vessel that branches off at an acute angle from a large main vessel using a microcatheter or guidewire can be difficult. In particular, when the main vessel is large, the microcatheter tends to bend, making it difficult to insert into the branch vessel, or even if it does, the tip of the microcatheter may slip out. Furthermore, when the branch vessel forms an acute angle with the main vessel, the tip of the microcatheter is likely to slip out of the branch vessel, making selection even more difficult.

In prostate arterial embolization, the internal iliac artery, which is the main blood vessel, has an inner diameter of 2-8 mm, while the branch vessels have an inner diameter of approximately 1 mm. In liver arterial embolization, the main blood vessel has an inner diameter of 2-5 mm, while the branch vessels have an inner diameter of approximately 1 mm, and there may be further branches. When a branch vessel has further branches, it becomes even more difficult to select the branch vessel using a microcatheter or guidewire.

The vascular model described in Patent Document 1 makes it difficult to evaluate the selectivity of long medical objects such as microcatheters and guidewires in thin branching blood vessels that branch off at acute angles from the main blood vessel, as described above.

The present invention has been made to solve the above-mentioned problems, and aims to provide a vascular model and an evaluation method for a medical elongated body that can evaluate the selectivity of a medical elongated body to a branch blood vessel that branches off at an acute angle so as to turn back from a main blood vessel.

The blood vessel model of the present invention, which achieves the above-mentioned object, has a main passageway that extends linearly to simulate a main blood vessel, and branch passageways that are narrower than the main passageway and simulate branch blood vessels that branch off from the main blood vessel, and is characterized in that it has a plurality of branch passageways that are lined up along the main passageway and have different branching angles with respect to the main passageway, and peripheral branch passageways that branch off from each of the branch passageways at a peripheral side away from the main passageway, and the branching angle of each of the branch passageways with respect to the main passageway is greater than 0 degrees and less than 90 degrees , when the branch passageway is defined as turning back in the opposite direction from the main passageway as 0 degrees, and each of the peripheral branch passageways provided at the peripheral of each of the branch passageways is another branch passageway .

The method for evaluating a medical elongated body according to the present invention, which achieves the above-mentioned object, is a method for evaluating a medical elongated body using a blood vessel model, and includes: a main passageway extending in a straight line that simulates a main blood vessel; a plurality of branch passageways that are narrower than the main passageway and are arranged along the main passageway to simulate branch blood vessels branching from the main blood vessel, and that have different branching angles relative to the main passageway; and peripheral branch passageways that branch off from each of the branch passageways on a peripheral side away from the main passageway, wherein the branching angle of each of the branch passageways with respect to the main passageway is greater than 0 degrees and less than 90 degrees, where 0 degrees is defined as the angle when the branch passageway turns back in the opposite direction from the main passageway, and each of the peripheral branch passageways provided at the peripheral of each of the branch passageways is another branch passageway , and the method includes the steps of: preparing a blood vessel model; inserting the medical elongated body into the main passageway and attempting to reach the peripheral branch passageway from the main passageway via the branch passageway; and determining whether the peripheral branch passageway is reached from the branch passageway.

The vascular model and evaluation method for medical elongated bodies configured as described above can evaluate the selectivity of medical elongated bodies to branch blood vessels that branch off at an acute angle so as to turn back from the main blood vessel.

The vascular model may have multiple branch passages with different branching angles relative to the main passage. This makes it possible to use a single vascular model to evaluate the selectivity of medical elongated bodies in branched blood vessels with various branching angles.

The blood vessel model may have multiple main passages with different inner diameters, with branch passages branching off from each of the main passages. This provides multiple combinations of main passages and branch passages, making it possible to reproduce branch vessels that branch off at acute angles from main vessels of various inner diameters in a single blood vessel model, thereby enabling the evaluation of the selectivity of medical elongated bodies.

The inner diameters of the multiple main passages with different inner diameters may decrease in stages toward the periphery. This allows the actual blood vessel diameter to be simulated and the blood vessel model to be made compact.

The vascular model may have at least one peripheral branch passage that branches off from the main passage on the peripheral side of the branch passage. This makes it possible to evaluate the selectivity of a medical elongated object that passes through multiple branches in succession.

The blood vessel model may have multiple branch passages with different branching angles relative to the main passage, and at least one of the peripheral branch passages located at the periphery of the branch passage may be another branch passage. This allows a peripheral branch passage located at the periphery of one of the branch passages to be reproduced by another branch passage, thereby enabling the blood vessel model to be realized compactly.

The main passage may be branched into multiple locations. This allows for efficient placement of multiple main passages, making it possible to compactly create a vascular model with multiple main passages. It also makes it possible to evaluate the selectivity of a medical elongated object that has passed through multiple branching main passages to branch blood vessels.

A group of branch passages, each with a different branch angle relative to the main passage, may be arranged in the extension direction of the main passage, at different positions circumferentially around the main passage. This allows the selection performance of a medical elongated body in various branch blood vessels to be evaluated using a single blood vessel model.

FIG. 2 is a plan view showing a blood vessel model according to the embodiment. FIG. 2 is a side view showing a blood vessel model according to the embodiment. FIG. 10 is a plan view showing a state in which a blood vessel model is used. FIG. 10 is a plan view showing a state in which a blood vessel model is used.

Embodiments of the present invention will now be described with reference to the drawings. Note that dimensions in the drawings may be exaggerated for the sake of explanation and may differ from the actual dimensions. Furthermore, in this specification and drawings, components that have substantially the same functions are designated by the same reference numerals, and redundant explanations will be omitted.

The vascular model 10 of this embodiment is a model that simulates a blood vessel in order to evaluate the selectivity of branched blood vessels of medical elongated objects such as microcatheters and guidewires. Note that the use of the vascular model 10 is not limited to evaluation of medical elongated objects, and it may also be used, for example, for training in procedures.

As shown in Figures 1 and 2, the blood vessel model 10 comprises two division simulation sections 11, two holding plates 12 sandwiching the division simulation sections 11, multiple connectors 13, and an insertion port 14. The two division simulation sections 11 are generally rectangular flat plates with grooves simulating blood vessels formed on their opposing surfaces 15. The two division simulation sections 11 are formed with plane symmetry. Therefore, when they overlap on the opposing surfaces 15, the grooves overlap, forming a blood vessel simulation section 20 simulating a blood vessel with a generally circular cross section. The division simulation section 11 is preferably transparent or translucent to allow visual observation of the interior and is preferably made of a flexible material similar to actual biological tissue. The material of the division simulation section 11 is not particularly limited, but examples include silicone resin and various elastomer resins such as SEBS, polyolefin elastomer, polyamide elastomer, acrylic elastomer, and fluorine-containing elastomer. In this embodiment, the material of the division simulation section 11 is silicone resin. The division simulation portion 11 is preferably formed using a mold, but the formation method is not particularly limited, and it may be formed, for example, by a 3D printer.

The holding plate 12 is a member that sandwiches the two flexible division simulation sections 11 to hold them in an overlapping state. Each holding plate 12 is a roughly rectangular flat plate that can cover the division simulation section 11. The holding plate 12 is preferably transparent or translucent so that the interior can be visually observed, and is formed from a hard material that can hold the flexible division simulation section 11. The constituent material of the holding plate 12 is not particularly limited, but examples include acrylic resin, ABS resin, acrylic resin, methacrylic resin, polycarbonate, melamine resin, styrene resin, hard polyvinyl chloride resin, fluororesin, glass, etc. In this embodiment, the constituent material of the holding plate 12 is acrylic resin.

The connector 13 is a member for holding the split simulation section 11 sandwiched between the holding plates 12. The connector 13 is composed of, for example, a bolt and nut that passes through through holes formed in the split simulation section 11 and the holding plates 12 and can hold the two holding plates 12 together. The configuration of the connector 13 is not particularly limited and may be, for example, a clamp.

The insertion port 14 is the site through which the medical elongated body is inserted into the blood vessel model 10. The insertion port 14 is located on the side end surfaces of the two divided simulation sections 11, and is connected to the opposing grooves so that it is sandwiched between them. The insertion port 14 is configured, for example, with a hemostatic valve having a three-way stopcock or a Y-connector. The insertion port 14 is the site through which the medical elongated body is inserted, and is connected to the communication passage 21 (described below) of the blood vessel simulation section 20. Note that insertion ports 14 equipped with hemostatic valves or the like may also be located at openings on the side end surfaces of the two divided simulation sections 11 other than the communication passage 21. This makes it easier to fill the interior of the blood vessel simulation section 20 with liquid and ensures that the liquid-filled state can be maintained effectively.

The vascular model 10 is a model with a substantially planar structure. The thickness of the vascular model 10 with a substantially planar structure is 100 mm or less, preferably 50 mm or less, and more preferably 30 mm or less.

Next, the blood vessel simulation portion 20 formed in the divided simulation portion 11 will be described in detail.
As shown in FIG. 1, the blood vessel simulation section 20 includes a communication passage 21 to which the insertion port 14 is connected, a plurality of main passages 30 that simulate main blood vessels, a plurality of branch passages 40 that simulate branch blood vessels that branch off from the main blood vessels, and an auxiliary passage 50 for venting air when the blood vessel simulation section 20 is filled with liquid.

The multiple main passages 30 include a base main passage 31 extending from the connecting passage 21, a first main passage 32 connected to the base main passage 31, a second main passage 33 branching off from the base main passage 31, a third main passage 34 connected to the second main passage 33, and a fourth main passage 35 connected to the third main passage 34.

The base-end main passage 31 extends linearly from the connecting passage 21. The inner diameter of the base-end main passage 31 is not particularly limited, but is, for example, 5 mm.

The first main passage 32 is located distally of the proximal main passage 31 and extends linearly from the proximal main passage 31. The first main passage 32 and the proximal main passage 31 are aligned coaxially. The inner diameter of the first main passage 32 is larger than that of the proximal main passage 31. The inner diameter of the first main passage 32 is not particularly limited, but is, for example, 8 mm. Note that the distal side refers to the side of the passage away from the insertion port 14 (the side in the direction of travel of the inserted elongated medical object). The proximal main passage 31 and the first main passage 32 are smoothly connected by the inner diameter tapering from the proximal main passage 31 to the first main passage 32.

The second main passage 33 is a passage that branches off from the proximal main passage 31 at a predetermined branching angle α. The second main passage 33 extends linearly from the proximal main passage 31. The inner diameter of the second main passage 33 is equal to the inner diameter of the proximal main passage 31. The inner diameter of the second main passage 33 is not particularly limited, but is, for example, 5 mm. The branching angle is defined as 0 degrees when one passage extending distally branches off from the other passage, and the other passage turns back to the opposite distal side (the insertion port 14 side) from the first passage, and as 180 degrees when the other passage extends in the same direction (distal side) as the first passage.

The third main passage 34 is located distal to the second main passage 33 and extends linearly from the second main passage 33. The third main passage 34 and the second main passage 33 are aligned coaxially. The inner diameter of the third main passage 34 is smaller than the inner diameter of the second main passage 33. The inner diameter of the third main passage 34 is not particularly limited, but may be, for example, 2 mm. The second main passage 33 and the third main passage 34 are smoothly connected by tapering the inner diameter from the second main passage 33 to the third main passage 34.

The fourth main passage 35 is located distal to the third main passage 34 and extends linearly from the third main passage 34. The fourth main passage 35 and the third main passage 34 are aligned coaxially. The inner diameter of the fourth main passage 35 is smaller than the inner diameter of the third main passage 34. The inner diameter of the fourth main passage 35 is not particularly limited, but is, for example, 1.2 mm.

A number of branch passages 40 are connected to the first main passage 32, the second main passage 33, the third main passage 34 and the fourth main passage 35, and are arranged in the extension direction of the main passage 30 and branch off from the main passage 30 at different branch angles.

The multiple branch passages 40 include a first branch passage 41, a second branch passage 42, a third branch passage 43, and a fourth branch passage 44 that branch off from the second main passage 33. The first branch passage 41, the second branch passage 42, the third branch passage 43, and the fourth branch passage 44 are lined up toward the distal end along the extension direction of the second main passage 33 and branch off from the second main passage 33. The axes of the first branch passage 41, the second branch passage 42, the third branch passage 43, and the fourth branch passage 44 are arranged on the same plane.

The first branch passage 41 branches off from the second main passage 33 at a branch angle θ1.

The second branch passage 42 branches off from the second main passage 33 at a branch angle θ2, more distal than the first branch passage 41. The branch angle θ2 is greater than the branch angle θ1.

The third branch passage 43 branches off from the second main passage 33 at a branch angle θ3, more distal than the second branch passage 42. The branch angle θ3 is greater than the branch angle θ2.

The fourth branch passage 44 branches off from the second main passage 33 at a branch angle θ4, more distal than the third branch passage 43. The branch angle θ4 is greater than the branch angle θ3.

Branch angles θ1 to θ4 are greater than 0 degrees and less than 90 degrees, and preferably greater than or equal to 30 degrees and less than or equal to 75 degrees. As an example, branch angle θ1 is 30 degrees, branch angle θ2 is 45 degrees, branch angle θ3 is 60 degrees, and branch angle θ4 is 75 degrees.

The branch passage 40 has a peripheral branch passage 45 that branches off from the second branch passage 42, the third branch passage 43, and the fourth branch passage 44 at a branch angle β. The branch angle β of the peripheral branch passage 45 is not particularly limited, but is greater than 0 degrees and less than 90 degrees, for example, 75 degrees.

The peripheral branch passage 45 branching from the second branch passage 42 is connected to communicate with the first branch passage 41. In other words, the first branch passage 41 is also a second peripheral branch passage that further branches at a branching angle γ from the peripheral branch passage 45 branching from the second branch passage 42.

The peripheral branch passage 45 branching from the third branch passage 43 is connected to communicate with the second branch passage 42. In other words, the second branch passage 42 is also a second peripheral branch passage that further branches at a branching angle γ from the peripheral branch passage 45 branching from the third branch passage 43.

The peripheral branch passage 45 branching from the fourth branch passage 44 is connected to communicate with the third branch passage 43. In other words, the third branch passage 43 is also a second peripheral branch passage that further branches at a branching angle γ from the peripheral branch passage 45 branching from the fourth branch passage 44.

The branching angle γ of the second peripheral branch passage is not particularly limited, but is greater than 0 degrees and less than 90 degrees, for example 90 degrees.

The inner diameters of the first branch passage 41, the second branch passage 42, the third branch passage 43, the fourth branch passage 44 and the peripheral branch passage 45 are smaller than the inner diameter of the second main passage 33, which is the main passage 30 from which the branches originate, and are, for example, 1 mm.

Similar to the second main passage 33 described above, a first branch passage 41, a second branch passage 42, a third branch passage 43, a fourth branch passage 44, and a peripheral branch passage 45 branch off from the third main passage 34 and the fourth main passage 35. The branch angles θ1 to θ4 of the branch passage 40 relative to the third main passage 34 or the fourth main passage 35 preferably match the branch angles θ1 to θ4 of the branch passage 40 relative to the second main passage 33 described above, but they do not have to match. Furthermore, the branch angle β of the peripheral branch passage 45 branching off the peripheral side of the third main passage 34 or the fourth main passage 35 and the branch angle γ of the second peripheral branch passage preferably match the branch angle β of the peripheral branch passage 45 branching off the peripheral side of the second main passage 33 and the branch angle γ of the second peripheral branch passage, but they do not have to match.

Two branch passage groups 46 consisting of a second branch passage 42, a third branch passage 43, and a fourth branch passage 44 branch off from the first main passage 32. The two branch passage groups 46 are connected in opposite circumferential directions of the first main passage 32. Therefore, the first main passage 32 and the two branch passage groups 46 are arranged on the same plane.

Next, we will explain a method for evaluating a medical elongated object using the vascular model 10 of this embodiment.

First, the tester conducting the evaluation test determines the main passage 30 and branch passage 40 into which the microcatheter 100 will be inserted. For example, the tester may decide to insert the microcatheter 100 from the first main passage 32 into one of the third branch passages 43, as shown in Figure 3.

The tester injects water, saline, a surfactant-containing solution, or the like into the blood vessel model 10 through the insertion port 14. This causes the water, saline, a surfactant-containing solution, or the like to flow into the blood vessel simulation portion 20 of the blood vessel model 10. Air inside the blood vessel model 10 is discharged to the outside through openings formed on the side end surfaces of the blood vessel simulation portion 20, auxiliary passages 50, or the like. This fills the inside of the blood vessel simulation portion 20 of the blood vessel model 10 with water, saline, a surfactant-containing solution, or the like. Alternatively, a surfactant or lubricating polymer may be applied to the inner surface of the blood vessel simulation portion 20 in advance, or a hydrophilic lubricating polymer containing acrylamide or a hydrophobic lubricating polymer such as a fluororesin may be applied as the lubricating polymer.

Next, the tester inserts a guiding catheter (not shown) through the insertion port 14 communicating with the communication passage 21, reaching its tip into the proximal main passage 31. Then, the tester inserts the microcatheter 100 into the guiding catheter, passing it from the communication passage 21 through the proximal main passage 31 to the first main passage 32. The tester then attempts to select the third branch passage 43 with the tip of the microcatheter 100 and push the microcatheter 100 into the third branch passage 43. This allows the tester to evaluate, using the vascular model 10, whether the microcatheter 100 was able to select the third branch passage 40 from the first main passage 32. Note that the inner diameter of the first main passage 32 is 8 mm, while the inner diameter of the third branch passage 43 is 1 mm, resulting in a large difference in inner diameter. Under these conditions, it is difficult to select the third branch passage 43. Therefore, it is effective to use a microcatheter 100 shaped with a curved tip. However, because the branching angle θ3 is an acute angle, even if the tip of the microcatheter 100 is inserted into the third branch passage 43, further pushing the microcatheter 100 may cause the microcatheter 100 to bend inside the first main passage 32 and prolapse toward the periphery, as shown by the dashed-dotted line in FIG. 3 , and possibly come out of the third branch passage 43. By using this vascular model 10, the tester can evaluate whether the microcatheter 100 has high supportability for feeding a guidewire passing through the microcatheter 100 into the third branch passage 43 without prolapse. Furthermore, by using this vascular model 10, the tester can evaluate whether the microcatheter 100 has branch vessel selectivity for pushing the microcatheter 100 toward the periphery by making the microcatheter 100 follow the guidewire after inserting the guidewire into the third branch passage 43.

If the tester decides to insert the microcatheter 100 from the second main passage 33 into, for example, the second branch passage 42, as shown in FIG. 4 , the tester inserts the microcatheter 100 through the insertion port 14 and passes through the connecting passage 21, the proximal main passage 31, and the second main passage 33. Next, the tester selects the second branch passage 42 with the tip of the microcatheter 100 and attempts to push the microcatheter 100 into the second branch passage 42. This allows the tester to evaluate, using the vascular model 10, whether the microcatheter 100 can select the second branch passage 42 from the second main passage 33. Note that the inner diameter of the second main passage 33 is 5 mm, which is smaller than the inner diameter (8 mm) of the first main passage 32. Therefore, it is easier to select a branch passage 40 than when using the microcatheter 100 to select one of the branch passages 40 from the first main passage 32. Furthermore, a peripheral branch passage 45 and a second peripheral branch passage (first branch passage 41) are further branched on the peripheral side of the second branch passage 42 branching from the second main passage 33. Therefore, using this vascular model 10, the tester can evaluate whether the microcatheter 100 can reach the peripheral branch passage 45 and the second peripheral branch passage (first branch passage 41) by following the guidewire without prolapsing. Furthermore, the first main passage 32 branches off from the proximal main passage 31. Therefore, at the branch point between the proximal main passage 31 and the first main passage 32, the force pushing the microcatheter 100 along the guidewire is not dispersed, and it is possible to evaluate whether the microcatheter 100 can follow the guidewire without prolapsing. The difference in the performance of the microcatheter 100 in terms of followability to the guidewire is brought about by a combination of multiple factors, such as the flexibility of the portion of the microcatheter 100 extending from the tip to the base end approximately 5 mm from the tip, the rigidity arrangement from that portion to approximately 30 mm from the base end, the shaft rigidity further to the base end, the outer diameter of the tip, kink resistance, slipperiness, the chamfered shape of the tip, the rigidity and slipperiness of the guidewire, and the clearance between the microcatheter 100 and the guidewire, but it mainly depends on the flexibility, rigidity arrangement, and outer diameter of the tip portion of the microcatheter 100. Therefore, when the difference in performance of the microcatheter 100 appears due to the multiple factors described above, it is effective to evaluate the performance difference using this vascular model 10.

If the tester decides to insert the microcatheter 100 from the third main passage 34 into one of the branch passages 40, the vascular model 10 can be used to perform the same evaluation as when inserting the microcatheter 100 from the second main passage 33 into one of the branch passages 40. The inner diameter of the third main passage 34 is 2 mm, which is smaller than the inner diameter of the second main passage 33, which is 5 mm. Therefore, the range over which the microcatheter 100 and guidewire can bend is narrow (the range over which the pushing force can escape is small), making it unlikely that differences in the performance of the microcatheter 100's ability to follow the guidewire will occur. However, when differences in the flexibility, rigidity arrangement, outer diameter, etc. of the tip portion of the microcatheter 100 are relatively large, differences in the performance of the microcatheter 100 are likely to become apparent, making it effective to evaluate these differences in performance using the vascular model 10.

If the tester decides to insert the microcatheter 100 from the fourth main passage 35 into one of the branch passages 40, the vascular model 10 can be used to perform the same evaluation as when inserting the microcatheter 100 from the second main passage 33 into one of the branch passages 40. The inner diameter of the fourth main passage 35 is 1.2 mm, which is smaller than the inner diameter of the second main passage 33 (5 mm) and the inner diameter of the third main passage 34 (2 mm). Therefore, the range over which the microcatheter 100 and guidewire can bend is even narrower (the range over which the pushing force escapes is smaller), making it less likely that differences in the microcatheter 100's ability to follow the guidewire will occur. However, when differences in the flexibility, rigidity arrangement, outer diameter, etc. of the tip portion of the microcatheter 100 are relatively large, differences in the performance of the microcatheter 100 are likely to become apparent, making it effective to evaluate these differences in performance using the vascular model 10.

As described above, the vascular model 10 of this embodiment has a main passage 30 that simulates a main blood vessel, and a branch passage 40 that is narrower than the main passage 30 and simulates a branch blood vessel that branches off from the main blood vessel. The branch angles θ1 to θ4 of the branch passage 40 relative to the main passage 30 are greater than 0 degrees and less than 90 degrees, with 0 degrees defined as the angle when the branch passage 40 turns back in the opposite direction relative to the main passage 30.

The vascular model 10 configured as described above can be used to evaluate the selection performance of a medical elongated body into a branch vessel that branches off at an acute angle from the main vessel.

The blood vessel model 10 has multiple branch passages 40 with different branch angles θ1 to θ4 relative to the main passage 30. This makes it possible to use a single blood vessel model 10 to evaluate the selectivity of medical elongated bodies in branch passages 40 with various branch angles θ1 to θ4.

The blood vessel model 10 also has multiple main passages 30 with different inner diameters, and branch passages 40 branching off from each main passage 30. This allows for multiple combinations of main passages 30 and branch passages 40, so that a single blood vessel model 10 can be used to reproduce branch vessels that branch off at acute angles as if turning back from main vessels of various inner diameters, allowing the selection performance of medical elongated bodies to be evaluated.

In addition, the blood vessel model 10 may have multiple main passages 30 with different inner diameters that do not branch off from the main passage 30 or the proximal main passage 31, but rather the inner diameters of the multiple main passages 30 with different inner diameters may gradually decrease toward the periphery. In this embodiment, the inner diameter of the second main passage 33 is 5 mm, the inner diameter of the third main passage 34 is 2 mm, and the inner diameter of the fourth main passage 35 is 1.2 mm, which gradually decrease in diameter. This allows for simulation of actual blood vessel diameters, and allows multiple main passages with different inner diameters to be efficiently arranged without gaps, making the blood vessel model 10 compact.

The vascular model 10 also has at least one peripheral branch passage 45 that branches off at the peripheral side of the branch passage 40, away from the main passage 30. This makes it possible to evaluate the selectivity of a medical elongated object that passes through multiple branches in succession.

The blood vessel model 10 also has multiple branch passages 40 with different branch angles relative to the main passage 30, and at least one of the peripheral branch passages 45 located at the end of a branch passage 40 is another branch passage 40. This allows a second peripheral branch passage located at the end of one of the branch passages 40 to be reproduced by another branch passage 40, allowing the blood vessel model 10 to be realized in a compact manner.

Furthermore, the main passages 30 are branched into multiple locations. This allows for efficient placement of multiple main passages 30, making it possible to compactly realize a vascular model 10 having multiple main passages 30. Furthermore, it is possible to evaluate the selectivity of a medical elongated body that has passed through multiple branched main passages 30 into a branch passage 40.

Furthermore, a plurality of branch passage groups 46, each of which has a plurality of branch passages 40 with different branch angles θ2 to θ4 relative to the main passage 30 lined up in the extension direction of the main passage 30, are provided at different positions circumferentially around the main passage 30. This makes it possible to evaluate the selectivity of medical elongated bodies in various branch passages 40 using a single blood vessel model 10.

In addition, the method for evaluating a medical elongated body using the blood vessel model 10 of this embodiment includes the steps of preparing a blood vessel model 10 having a main passage 30 that simulates a main blood vessel, and a branch passage 40 that is narrower than the main passage 30 and simulates a branch blood vessel branching off from the main blood vessel, and the branching angles θ1 to θ4 of the branch passage 40 relative to the main passage 30 are greater than 0 degrees and less than 90 degrees, where 0 degrees is defined as the angle when the branch passage 40 turns back in the opposite direction relative to the main passage 30; inserting the medical elongated body into the main passage 30 and attempting to reach the branch passage 40 from the main passage 30; and determining whether the branch passage 40 is reached.

The evaluation method configured as described above can easily evaluate the selectivity of a medical elongated body to a branch blood vessel that branches off at an acute angle from a main blood vessel.

The present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical concept of the present invention.

For example, the vascular model 10 may be a jig. For example, the vascular model 10 may be connected to a sensor such as an autograph. This makes it possible to detect the force acting on the vascular model 10 when inserting a medical elongated object into the vascular model 10, the amount of movement of the vascular model 10, etc. Furthermore, the blood vessels simulated by the vascular model 10 may be, but are not limited to, the prostatic artery, uterine artery, or hepatic artery. Alternatively, to help beginners get used to the model, some branch passages may be provided with a branch angle of 90 degrees or more relative to the main passage.

This application is based on Japanese Patent Application No. 2020-114084, filed on July 1, 2020, the disclosures of which are incorporated herein by reference in their entirety.

10 Blood vessel model 11 Divided simulation section 12 Holding plate 13 Connector 14 Insertion port 15 Opposing surface 20 Blood vessel simulation section 21 Connecting passage 30 Main passage 31 Proximal main passage 32 First main passage 33 Second main passage 34 Third main passage 35 Fourth main passage 40 Branch passage 41 First branch passage 42 Second branch passage 43 Third branch passage 44 Fourth branch passage 45 Peripheral branch passage 46 Branch passage group 50 Auxiliary passage 100 Microcatheter (medical elongated body)

Claims (6)

A blood vessel model having a main passageway extending linearly to simulate a main blood vessel, and a branch passageway narrower than the main passageway to simulate a branch blood vessel branching from the main blood vessel,
a plurality of branch passages arranged along the main passage and having different branch angles with respect to the main passage;
a peripheral branch passage branching off from each of the branch passages at a peripheral side distant from the main passage,
a branch angle of each of the branch passages with respect to the main passage is greater than 0 degrees and less than 90 degrees, where 0 degrees is defined as the angle when the branch passage turns back in the opposite direction to the main passage;
A blood vessel model, characterized in that each of the peripheral branch passages provided at the periphery of each of the branch passages is another branch passage . 2. The blood vessel model according to claim 1 , wherein the blood vessel model has a plurality of main passages with different inner diameters, and the branch passages branch off from each of the main passages. 3. The blood vessel model according to claim 1 , wherein the inner diameters of the plurality of main passages having different inner diameters decrease stepwise toward the periphery. 4. The blood vessel model according to claim 1, wherein the main passage is branched into a plurality of main passages. The blood vessel model according to any one of claims 1 to 4, characterized in that a group of branch passages, each of which has a plurality of branch passages with different branch angles relative to the main passage arranged in the extension direction of the main passage, is provided at different positions in the circumferential direction of the main passage. A method for evaluating a medical elongated object using a blood vessel model, comprising:
preparing a blood vessel model having a main passageway extending linearly to simulate a main blood vessel, a plurality of branch passageways which are narrower than the main passageway and which are arranged along the main passageway to simulate branch blood vessels branching from the main blood vessel, and which have different branching angles relative to the main passageway, and peripheral branch passageways which branch off from each of the branch passageways at a peripheral side away from the main passageway , wherein the branching angle of each of the branch passageways relative to the main passageway is greater than 0 degrees and less than 90 degrees , where 0 degrees is defined as the angle when the branch passageway turns back in the opposite direction relative to the main passageway, and each of the peripheral branch passageways provided at the peripheral of each of the branch passageways is another branch passageway ;
a step of inserting the medical elongate body into the main passage and attempting to reach the peripheral branch passage from the main passage via the branch passage ;
and determining whether or not the branch passage reaches the peripheral branch passage .