Catheter device

Abstract

The purpose of the present invention is to provide a catheter device capable of more assuredly accessing a prescribed living body part through the inside of a blood vessel. A catheter device 3 comprises: a long first shaft 32 having a lumen for connecting a first opening formed at an end part on the hand side with a second opening formed at an end part 321 on the insertion side; and a self-expandable fixing member 35 disposed on the outer circumferential surface of the first shaft 32. The first shaft 32 has a bent part 324 provided in a section including the end part 321 on the insertion side and bent in a direction intersecting the direction of the longitudinal axis 325 of the first shaft 32. In a direction orthogonal to the direction of the longitudinal axis 325, a distance L1 in the bent part 324 between the end part 324 on the insertion side and the longitudinal axis 325 is longer than the outer diameter D1 of the fixing member 35 in a maximum expansion state.

Description

Catheter Device

[0001] The present invention relates to a catheter device used in the treatment of brain diseases and in a fluid circulation system.

[0002] When a brain disease, such as cerebral infarction, occurs, the blood flow that supplies oxygen to brain cells is blocked, which can damage the brain cells. Therefore, when a cerebral infarction occurs, early reperfusion of blood flow is necessary. One proposed treatment for cerebral infarction is to inject oxygenated fluid, such as cerebrospinal fluid, into the patient's body cavity where the cerebrospinal fluid is present and then drain the fluid outside the body cavity to circulate the fluid and directly supply oxygen to oxygen-deficient brain cells.

[0003] Patent Document 1 discloses that the subarachnoid space is accessed from the lumbar spine to treat and circulate cerebrospinal fluid. However, when the lumbar spine is used as a location for accessing the subarachnoid space from outside the living body, there are the following advantages and disadvantages.

[0004] That is, when the lumbar spine is used as the location for accessing the subarachnoid space from outside the living body, the subarachnoid space can be accessed simply by puncturing with a device, which has the advantage of placing less strain on the patient.However, there is a disadvantage in that it takes a certain amount of time to see the effects of injecting and draining fluid because there is a certain distance between the lumbar spine, which is the puncture site, and the brain, which is the treatment site.

[0005] It is also possible to use the ventricles and cisterns as locations for accessing the subarachnoid space from outside the body. This has the advantage that the effects of injecting and draining fluid can be obtained quickly because the fluid is supplied directly to the brain. However, it has the disadvantage that accessing the ventricles and cisterns requires inserting a device into the head or performing craniotomy to remove part of the skull, which places a heavy burden on the patient.

[0006] Patent Literature 2 (Patent Document 2) discloses a system and method for accessing the subarachnoid space, including intracranial cisterns, to administer a therapeutic agent. The drug delivery device described in Patent Literature 2 includes a guide catheter, an anchor, and a puncturing element. The anchor is self-expanding and is positioned in the inferior petrosal sinus. The puncturing element is delivered from the inferior petrosal sinus through the dura mater and arachnoid mater to the cerebellopontine horn layer (CP Angle cistern).

[0007] However, the anchor of the drug delivery device described in Patent Document 2 is positioned on the side of the puncturing element in the direction of travel, which may interfere with the puncturing element during puncturing. Furthermore, the puncturing angle may be shallow relative to the inner wall of the blood vessel, which may result in an inability to puncture at an appropriate angle. Therefore, there is room for improvement in terms of ensuring reliable puncturing by the puncturing element.

[0008] JP 2020-536618 A U.S. Patent No. 11,013,900

[0009] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a catheter device that can more reliably access a predetermined body site from inside a blood vessel.

[0010] The present invention is (1) a catheter device for accessing a biological site located near a blood vessel from inside the blood vessel, comprising: a long first shaft having an inner cavity that connects a first opening formed at a proximal end with a second opening formed at an insertion end; and a self-expandable fixing member arranged on the outer surface of the first shaft, wherein the first shaft has a bent portion that is provided in a portion including the insertion end and is bent in a direction that intersects with the longitudinal axis of the first shaft, and the distance between the insertion end at the bent portion and the longitudinal axis in a direction perpendicular to the longitudinal axis is longer than the outer diameter of the fixing member in a maximum expanded state.

[0011] According to the catheter device of (1) above, the elongated first shaft has a bent portion provided in a portion including the insertion end. The bent portion is bent in a direction intersecting the longitudinal axis of the first shaft. Therefore, the bent portion is not parallel to the longitudinal axis of the first shaft inside the blood vessel. Therefore, the inner wall of the blood vessel is located on an extension of the insertion end of the first shaft. This allows a medical instrument, such as a needle, guided by the first shaft to reliably contact the inner wall of the blood vessel. Furthermore, in a direction perpendicular to the longitudinal axis of the first shaft, the distance between the insertion end of the bent portion of the first shaft and the longitudinal axis of the first shaft is longer than the outer diameter of the self-expandable fixing member disposed on the outer peripheral surface of the first shaft in the maximum expanded state. This allows the insertion end of the first shaft to reliably contact the inner wall of the blood vessel. Therefore, a medical instrument, such as a needle, guided by the first shaft can more reliably contact the inner wall of the blood vessel. This allows the catheter device (1) to be easily positioned from inside a blood vessel relative to a living body part located near the blood vessel, thereby enabling more reliable access.

[0012] (2) It is preferable that the catheter device of (1) above further includes an elongated second shaft having an internal space capable of accommodating the first shaft and the fixing member.

[0013] According to the catheter device of (2) above, the elongated second shaft has an internal space capable of accommodating the first shaft and the fixing member. Therefore, the second shaft can be guided to the vicinity of a biological site with the first shaft and the fixing member housed within the internal space. When the fixing member emerges from the internal space of the second shaft, it expands due to its own self-expanding function and is positioned within a blood vessel near the biological site. When the bent portion of the first shaft emerges from the internal space of the second shaft, it bends in a direction intersecting the longitudinal axis of the first shaft near the biological site. This allows the catheter device of the present invention to more reliably guide the first shaft and the fixing member to the vicinity of a biological site via the second shaft, thereby enabling more reliable access to a biological site located near the blood vessel from within the blood vessel.

[0014] (3) It is preferable that the catheter device of (1) or (2) above further includes a catheter that can be inserted into the lumen of the first shaft.

[0015] According to the catheter device of (3) above, the catheter is inserted into the lumen of the first shaft and is guided to the vicinity of the living body part by the first shaft.

[0016] (4) In the catheter device of (3) above, the catheter preferably has a contrast marker provided at the end of the insertion side.

[0017] According to the catheter device of (4) above, when the operator is making the catheter access a living body part, the operator can confirm the position of the end of the catheter on the insertion side under X-ray fluoroscopy.

[0018] (5) The catheter device of (3) or (4) above preferably further comprises a medical instrument that can access the biological site, and the catheter preferably has a lumen through which the medical instrument can be inserted.

[0019] According to the catheter device of (5) above, a medical instrument such as a needle that can access a living body part located near a blood vessel is inserted into the lumen of the catheter and guided to the vicinity of the living body part by the catheter.

[0020] (6) In the catheter device of (5) above, the medical instrument has a long wire and a puncture portion provided at the end of the wire, and it is preferable that the bending modulus of the wire is smaller than the bending modulus of the first shaft.

[0021] The shape of the bent portion of the first shaft changes depending on the course and inner diameter of the blood vessel. According to the catheter device of (6) above, the flexural modulus of the wire of the medical instrument is smaller than that of the first shaft, so the wire of the medical instrument deforms to fit the shape of the bent portion of the first shaft. This prevents the insertion end of the first shaft from shifting from a predetermined position due to the wire being inserted into the lumen of the catheter. This allows the puncture portion at the distal end of the wire to more reliably puncture the targeted location.

[0022] (7) In the catheter device of (6) above, it is preferable that the medical instrument has a contrast marker provided at the puncture portion, and that the contrast marker is positioned at a predetermined position relative to the catheter when at least a portion of the puncture portion is exposed from the lumen of the catheter when the puncture portion punctures the biological site.

[0023] According to the catheter device of (7) above, when the surgeon inserts the puncture portion of the medical instrument into a biological site, the contrast marker provided at the puncture portion is positioned at a predetermined position relative to the catheter under X-ray fluoroscopy, allowing the surgeon to confirm the appropriate length at which at least a portion of the puncture portion is exposed from the lumen of the catheter.

[0024] (8) In any of the catheter devices (1) to (7) above, it is preferable that the fixing member is connected to the outer surface of the first shaft only at the first end on the proximal side, and is not fixed to the first shaft at the second end on the insertion side.

[0025] According to the catheter device of (8) above, because the fixing member is not fixed to the first shaft at the second insertion end, the insertion end of the first shaft can be positioned freely from inside the fixing member. Therefore, compared to when the fixing member is fixed to the first shaft at the second insertion end, the degree of freedom in the position of the insertion end of the first shaft is improved. This allows the insertion end of the first shaft to be positioned toward the inner wall of the blood vessel in a more natural manner and to deform. In other words, when the insertion end of the first shaft abuts against the target position on the inner wall of the blood vessel, less external force is applied to the first shaft, thereby reducing the load on the entire catheter device and the living body, such as the blood vessel. Furthermore, since the distance between the insertion end of the bent portion of the first shaft and the longitudinal axis of the first shaft in a direction perpendicular to the longitudinal axis of the first shaft is longer than the outer diameter of the fixation member in the maximum expanded state, the insertion end of the first shaft can be positioned toward the inner wall of the blood vessel or can be deformed while suppressing change in direction (i.e., angle) of the insertion end of the first shaft, regardless of the expanded state of the fixation member. This allows the catheter device of (8) above to accommodate the course and inner diameter of various blood vessels.

[0026] (9) In any of the catheter devices (1) to (8) above, it is preferable that the length of the portion of the first shaft extending toward the insertion side beyond the second end of the fixing member on the insertion side is longer than the outer diameter.

[0027] According to the catheter device of (9) above, the insertion end of the first shaft can reliably contact the inner wall of the blood vessel regardless of the course and inner diameter of the blood vessel. Therefore, a medical instrument such as a needle guided by the first shaft can more reliably contact the inner wall of the blood vessel. This allows the catheter device of (9) above to more reliably access a living body part located near the blood vessel from inside the blood vessel.

[0028] (10) In the catheter device according to any one of (1) to (9) above, it is preferable that the first shaft has a radiopaque marker provided at the end on the insertion side.

[0029] According to the catheter device of (10) above, when the first shaft is made to access a living body part, the surgeon can check the position of the insertion side end of the first shaft under X-ray fluoroscopy.

[0030] (11) In any of the catheter devices (1) to (10) above, it is preferable that the fixing member has a plurality of struts and has a structure that does not block blood flow inside the blood vessel.

[0031] According to the catheter device of (11) above, even when the fixing member is deployed and the catheter device is indwelled, it is possible to prevent the blood flow inside the blood vessel from being blocked by the struts of the fixing member, and it is also possible to suppress the formation of thrombus inside the blood vessel in which the fixing member is placed.

[0032] (12) In the catheter device of (11) above, it is preferable that the fixing member has a first portion having a constant diameter in the direction of the longitudinal axis and a second portion having a diameter that gradually decreases in the direction of the longitudinal axis, and that the spacing between adjacent struts in the second portion is wider than the spacing between adjacent struts in the first portion.

[0033] According to the catheter device of (12) above, the spacing between adjacent struts in the second section intersecting the blood flow direction inside the blood vessel in which the fixing member is disposed is wider than the spacing between adjacent struts in the first section, thereby preventing the struts from interfering with blood components and causing thrombus formation. Meanwhile, the first section, which has a constant diameter in the direction of the longitudinal axis of the first shaft, abuts against the inner wall of the blood vessel similar to a general stent, thereby fixing the position of the first shaft relative to the catheter device. Therefore, the fixing member can maintain close contact and fixation with the inner wall of the blood vessel in the first section while preventing thrombus formation in the second section.

[0034] (13) The catheter device of (1) above further comprises a long second shaft having an internal space capable of accommodating the first shaft and the fixing member, and a catheter that can be inserted into the inner cavity of the first shaft, and it is preferable that the first shaft, the second shaft, and the catheter can all be operated independently of each other.

[0035] According to the catheter device of (13) above, the surgeon can independently operate the first shaft, the second shaft, and the catheter according to the course of the blood vessel and the inner diameter of the blood vessel, so that the catheter device of (13) above can more reliably access a biological site located near the blood vessel from inside the blood vessel.

[0036] According to the present invention, a catheter device can be provided that can more reliably access a predetermined body site from inside a blood vessel.

[0037] FIG. 1 is a schematic diagram showing a liquid circulation system in which a catheter device according to an embodiment of the present invention is used; FIG. 2 is a schematic diagram showing another liquid circulation system in which a catheter device according to this embodiment is used; FIG. 3 is a schematic diagram showing a catheter device according to this embodiment; FIG. 4 is a schematic diagram showing the vicinity of a fixing member of a catheter device according to this embodiment; FIG. 5 is a schematic diagram explaining a connection structure of a fixing member to a guiding catheter; FIG. 6 is a schematic diagram showing the state of a bent portion of this embodiment according to the state of a blood vessel; FIG. 7 is a schematic diagram explaining the relationship between a guiding catheter and a needle; FIG. 8 is a schematic diagram explaining the relationship between a guiding catheter and a needle; FIG. 9 is a schematic diagram explaining the relationship between a guiding catheter and a needle; FIG. 10 is a schematic diagram showing the relationship between a guiding catheter and a needle; FIG. 11 is a schematic diagram showing the relationship between a guiding catheter and a needle; FIG. 12 is a schematic diagram showing a fixing member of this embodiment; FIG. 13 is a schematic diagram showing an exhaust catheter and a needle according to a first specific example; FIG. 14 is a schematic diagram showing an exhaust catheter and a needle according to a second specific example; and FIG. 15 is a schematic diagram showing an exhaust catheter and a needle according to a third specific example.

[0038] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. The embodiments described below are preferred specific examples of the present invention, and therefore various technically preferable limitations are applied. However, the scope of the present invention is not limited to these aspects unless otherwise specified in the following description to the effect that the present invention is specifically limited. Furthermore, in each drawing, similar components are designated by the same reference numerals, and detailed descriptions thereof will be omitted where appropriate.

[0039] Fig. 1 is a schematic diagram showing a liquid circulation system in which a catheter device according to an embodiment of the present invention is used. Note that the system in which the catheter device according to this embodiment is used is not limited to the liquid circulation system shown in Fig. 1.

[0040] The fluid circulation system 2 shown in FIG. 1 circulates a fluid by injecting the fluid into a cavity containing the subject's cerebrospinal fluid (CSF) and then discharging the fluid to the outside of the cavity. CSF is primarily contained in the subarachnoid space and ventricles. That is, the cavities containing CSF include the subarachnoid space and ventricles. One of the subarachnoid spaces of the cisterns is the cerebellopontine angle cisterna (CP Angle cisterna). Therefore, the cerebellopontine angle cisterna is also included in the cavities of this embodiment.

[0041] The liquid injected into the cavity may be, for example, a liquid with an oxygen concentration higher than that of normal cerebrospinal fluid (i.e., a highly oxygenated solution). However, the liquid injected into the cavity is not limited to a highly oxygenated solution. For example, the liquid injected into the cavity may be a drug-containing liquid obtained by adding a drug to cerebrospinal fluid during extracorporeal circulation, or may be cerebrospinal fluid that has been filtered to remove undesirable substances during extracorporeal circulation. Alternatively, the liquid injected into the cavity may be cerebrospinal fluid that has been subjected to some kind of treatment, such as irradiation with energy or heating.

[0042] Furthermore, in the initial stage of treatment, the liquid injected into the containing cavity may be lactated Ringer's solution as a substitute for cerebrospinal fluid. In this embodiment, cerebrospinal fluid, artificial cerebrospinal fluid such as lactated Ringer's solution, a mixture of cerebrospinal fluid and lactated Ringer's solution, physiological saline, medicinal solutions, and distilled water for injection may be collectively referred to as liquid. In the following description, for convenience of explanation, a case where the liquid injected into the containing cavity is a highly oxygenated solution may be given as an example.

[0043] 1, the liquid circulation system 2 includes an inlet line 21, an outlet line 22, and a liquid delivery unit 23. The liquid circulation system 2 may also include an oxygenation mechanism 24, an oxygen supply source 25, and a heat exchanger 26. The oxygenation mechanism 24, the oxygen supply source 25, and the heat exchanger 26 are each an example of a "treatment unit" of the present invention.

[0044] The infusion line 21 has a catheter and is inserted into the receiving cavity via either the head or back of the subject, and injects a liquid into the receiving cavity as indicated by arrow A1 in FIG. 1 . As illustrated in FIG. 1 , the back into which the infusion line 21 is inserted is not particularly limited as long as it ensures the safety of the subject during insertion and placement, and examples thereof include the spinal cavity near the lumbar vertebrae. Also, as illustrated in FIG. 1 , the head into which the infusion line 21 is inserted includes at least one of the cistern and the ventricle. Depending on the delivery location, the infusion line 21 may or may not penetrate the brain parenchyma, and a suitable method is selected accordingly. For example, access routes used in common ventricular drainage and cisternal drainage procedures are preferred.

[0045] The drainage line 22 includes a catheter device 3 and is inserted into the interior of the housing cavity via the subject's internal jugular vein 41. As shown in Figure 1, for example, the drainage line 22 passes from the internal jugular vein 41 through the inferior petrosal sinus 42 and is inserted into the interior of the housing cavity from the inferior petrosal sinus 42. Details of the access of the drainage line 22 to the interior of the housing cavity will be described below.

[0046] The cavity containing cerebrospinal fluid (e.g., the subarachnoid space and the ventricle) is a substantially closed space. A certain pressure, such as intracranial pressure, is applied inside the cavity. Therefore, when the drain line 22 is inserted into the cavity, the fluid (e.g., cerebrospinal fluid) inside the cavity is drained to the outside of the cavity, as indicated by arrows A2 and A3 in FIG. 1 .

[0047] The catheter device 3 has a guiding catheter 32. The guiding catheter 32 of this embodiment is an example of a "first shaft" of the present invention. The catheter device 3 may further have a guiding sheath 31 and a drainage catheter 33. The guiding sheath 31 of this embodiment is an example of a "second shaft" of the present invention. The drainage catheter 33 of this embodiment is an example of a "catheter" of the present invention. The liquid drained through the drainage catheter 33 is supplied to the oxygenation mechanism 24.

[0048] The oxygenation mechanism 24 is connected to the oxygen supply source 25 via a first pipe 271. The oxygenation mechanism 24 mixes a liquid such as cerebrospinal fluid supplied through the discharge line 22 with oxygen supplied from the oxygen supply source 25 through the first pipe 271 as indicated by an arrow A4 in Fig. 1 , to generate oxygenated cerebrospinal fluid.

[0049] The oxygenation mechanism 24 is also connected to the heat exchanger 26 via a second pipe 272 and a third pipe 273. As indicated by arrow A5 in FIG. 1 , the oxygenation mechanism 24 supplies oxygenated cerebrospinal fluid to the heat exchanger 26 via the second pipe 272. The heat exchanger 26 adjusts the temperature of the cerebrospinal fluid supplied from the oxygenation mechanism 24 via the second pipe 272. As indicated by arrow A6 in FIG. 1 , the heat exchanger 26 supplies the temperature-adjusted cerebrospinal fluid to the oxygenation mechanism 24 via the third pipe 273. The oxygenation mechanism 24 then supplies the oxygenated, temperature-adjusted cerebrospinal fluid to the infusion line 21 as a highly oxygenated solution. An example of the oxygenation mechanism 24 is a hollow fiber membrane oxygenator for adding oxygen to blood.

[0050] The liquid delivery unit 23 is provided in the infusion line 21 and circulates the liquid supplied from the oxygenation mechanism 24. The liquid delivery unit 23 may be provided in the discharge line 22, or may be provided in both the infusion line 21 and the discharge line 22. Examples of the liquid delivery unit 23 include an infusion pump and a syringe pump.

[0051] As indicated by arrow A1 in FIG. 1 , the fluid delivery unit 23 delivers fluid to the infusion line 21, and the fluid is infused into the cavity through the infusion line 21 from either the head or back of the subject. As described above, the cavity containing cerebrospinal fluid (e.g., the subarachnoid space and the ventricle) is a substantially closed space. Furthermore, a certain pressure, such as intracranial pressure, is applied inside the cavity. Therefore, when the infusion line 21 injects fluid into the cavity, the fluid (e.g., cerebrospinal fluid) inside the cavity is pushed out of the cavity through the discharge line 22, including the catheter device 3, as indicated by arrows A2 and A3 in FIG. 1 . In this manner, the fluid delivery unit 23 circulates the fluid.

[0052] Next, other liquid circulation systems in which the catheter device according to this embodiment is used will be described. Where the components of the other liquid circulation system 2A are similar to the components of the liquid circulation system 2 described above with reference to Fig. 1, redundant explanations will be omitted as appropriate, and the following description will focus on the differences. As mentioned above, the system in which the catheter device according to this embodiment is used is not limited to the liquid circulation system shown in Fig. 2.

[0053] Fig. 2 is a schematic diagram showing another liquid circulation system in which the catheter device according to this embodiment is used. The liquid circulation system 2A shown in Fig. 2 includes an inlet line 21A, an outlet line 22, and a liquid delivery unit 23. The outlet line 22 and the liquid delivery unit 23 are as described above with reference to Fig. 1. The liquid circulation system 2A may also include an oxygenation mechanism 24, an oxygen supply source 25, and a heat exchanger 26. The oxygenation mechanism 24, the oxygen supply source 25, and the heat exchanger 26 are as described above with reference to Fig. 1.

[0054] The infusion line 21A includes a catheter device 3A similar to the catheter device 3 included in the discharge line 22. The catheter device 3A includes a guiding catheter 32. The catheter device 3A may include a guiding sheath 31 and an injection catheter 34. The injection catheter 34 of this embodiment is an example of a "catheter" of the present invention. The infusion line 21A is inserted into the interior of the housing cavity via the subject's internal jugular vein 41 and injects a liquid into the interior of the housing cavity as indicated by arrows A7 and A8 in FIG. 2. As shown in FIG. 2, for example, the infusion line 21A passes from the internal jugular vein 41 through the inferior petrosal sinus 42 and is inserted from the inferior petrosal sinus 42 into the interior of the housing cavity. The infusion line 21A accesses the interior of the housing cavity in the same manner as the discharge line 22 accesses the interior of the housing cavity.

[0055] In the liquid circulation system 2A shown in Fig. 2, the infusion line 21A passes from the internal jugular vein 41 on either the right or left side of the subject through one inferior petrosal sinus 42 and is inserted into the interior of the housing cavity from one inferior petrosal sinus 42. The drainage line 22 passes from the internal jugular vein 41 on the other side of the subject through the other inferior petrosal sinus 42 and is inserted into the interior of the housing cavity from the other inferior petrosal sinus 42. As described above with reference to Fig. 1, details of the access of the drainage line 22 to the interior of the housing cavity will be described later. The other configurations are similar to those of the liquid circulation system 2 described above with reference to Fig. 1.

[0056] The fluid circulation system 2A shown in Figure 2 has the advantages of reducing the burden on the patient because there is no need to puncture the head, and of delivering treated fluid directly to the brain, making it easier to achieve therapeutic effects more quickly. Furthermore, by separating the infusion line 21A and the drainage line 22 and placing them in the left and right inferior petrosal sinuses 42, it is possible to prevent the injected fluid from being immediately drained.

[0057] Next, the catheter device according to this embodiment will be described with reference to the drawings. Fig. 3 is a schematic diagram showing the catheter device according to this embodiment. Fig. 4 is a schematic diagram showing the vicinity of the fixing member of the catheter device according to this embodiment.

[0058] 1 and 2, the catheter device 3 of this embodiment is included in the discharge line 22. As described above with reference to Fig. 2, the catheter device 3A of this embodiment is included in the infusion line 21A. The structure and shape of the infusion catheter 34 of the catheter device 3A are similar to the structure and shape of the discharge catheter 33 of the catheter device 3. Therefore, the catheter device according to this embodiment will be described below using the catheter device 3 included in the discharge line 22 as an example.

[0059] The catheter device 3 includes a guiding catheter 32 and a fixing member 35. The catheter device 3 may include a guiding sheath 31 and a drainage catheter 33. A connector 36 is attached to the hub of the guiding sheath 31. The connector 36 has a valve body formed of an elastic member and holds the guiding catheter 32 relative to the guiding sheath 31.

[0060] The guiding sheath 31 penetrates the skin 48 from the outside 49 of the living body, passes through the internal jugular vein 41, and is placed in the inferior petrosal sinus 42. In the example shown in Fig. 3 , a distal end 311 of the guiding sheath 31 is placed at a junction 411 between the internal jugular vein 41, the inferior petrosal sinus 42, and the jugular bulb 44. The guiding sheath 31 is formed as an elongated shaft, and has an internal space capable of accommodating the guiding catheter 32 and the fixing member 35.

[0061] The guiding catheter 32 is formed as a long shaft and has an inner cavity that connects a first opening formed at the proximal end with a second opening formed at the insertion end. The "proximal side" refers to the side where the operator operates the catheter device 3, i.e., the proximal side from the operator's perspective. The "insertion side" refers to the side where the catheter device 3 is inserted into the living body and advances, i.e., the distal side from the operator's perspective.

[0062] 3, the distal end 321 of the guiding catheter 32 passes through the lumen of the guiding sheath 31, i.e., passes through the skin 48 from the outside 49 of the living body, passes through the internal jugular vein 41, and is positioned in the inferior petrosal sinus 42. In this specification, the "tip" is an example of the "insertion side end" of the present invention.

[0063] The fixing member 35 is disposed on the outer peripheral surface of the guiding catheter 32. Specifically, as shown in FIGS. 3 and 4 , the fixing member 35 is connected to and fixed to the outer peripheral surface of the guiding catheter 32 only at a first end 353 on the proximal side, and is not fixed to the guiding catheter 32 at a second end 354 on the insertion side. As shown in FIG. 3 , the fixing member 35 is expanded and disposed inside the inferior petrosal sinus 42 in the vicinity of the junction 411, and fixes the infusion line 21A (see FIG. 2 ) and the drainage line 22 inserted from the inferior petrosal sinus 42 into the cerebellopontine angle cistern 43. Specifically, the fixing member 35 functions as an anchor in its expanded state, and suppresses movement of the guiding catheter 32 in the direction of the longitudinal axis 325 (i.e., the extension direction) and rotational movement around the longitudinal axis 325.

[0064] The fixing member 35 itself has an expandable function, and when released from the constraint, it expands by elastic force and returns to its pre-contracted shape. That is, the fixing member 35 of this embodiment functions as a self-expanding fixing member, similar to, for example, a self-expanding stent. The fixing member 35 has struts as thin, linear wires, similar to, for example, a stent, and is formed into a tubular skeleton as a whole. The structure of the fixing member 35 having struts will be described in detail below.

[0065] The fixing member 35 is contracted when housed in the internal space of the guiding sheath 31. On the other hand, when the fixing member 35 passes through the opening formed in the distal end 311 of the guiding sheath 31 and comes out of the guiding sheath 31, the applied stress is released and the fixing member 35 expands by its own elastic force, restoring it to its pre-contracted shape. When the fixing member 35 is housed in the internal space of the guiding sheath 31 through the opening formed in the distal end 311 of the guiding sheath 31, it contracts again.

[0066] 3 , the drainage catheter 33 can be inserted into the lumen of the guiding catheter 32. A distal end 331 of the drainage catheter 33 passes through the lumen of the guiding catheter 32, i.e., passes through the skin 48 from the outside 49 of the living body, passes through the internal jugular vein 41, passes through the dura mater 46 and the arachnoid mater 47, and is positioned in the cerebellopontine angle cistern 43 between the arachnoid mater 47 and the brainstem 45.

[0067] In this way, the catheter device 3 according to this embodiment accesses a biological part located near a blood vessel from inside the blood vessel. In the example shown in Fig. 3, the cerebellopontine angle cistern 43 is an example of a "biological part" according to the present invention. Note that the "biological part" according to the present invention is not limited to the cerebellopontine angle cistern 43, nor is it limited to a space or cavity within a living body. The "biological part" according to the present invention may be biological tissue such as an organ.

[0068] For example, when the injection lines 21, 21A inject liquid into the interior of the receiving cavity, the liquid inside the cerebellopontine angle cistern 43 passes from the tip 331 of the discharge catheter 33 through the lumen of the discharge catheter 33 as indicated by arrow A11 in FIG. 3, and is discharged from the base end 333 of the discharge catheter 33 to the outside of the cerebellopontine angle cistern 43, i.e., to the outside 49 of the living body, as indicated by arrow A12 in FIG. 3.

[0069] When the injection line 21A injects liquid into the interior of the accommodation cavity using the catheter device 3A, the liquid passes through the lumen of the injection catheter 34 from the base end of the injection catheter 34 in the direction opposite to the arrow A12 shown in FIG. 3, and is injected into the interior of the cerebellopontine angle cistern 43 from the tip end of the injection catheter 34 in the direction opposite to the arrow A11 shown in FIG. 3.

[0070] Here, the fixing member 35 functions as an anchor in its expanded state to fix the guiding catheter 32 in an appropriate position. Therefore, when the infusion line 21A (see FIG. 2 ) and the drainage line 22 are inserted from the inferior petrosal sinus 42 to the cerebellopontine angle cistern 43, longitudinal movement and rotational movement about the longitudinal axis 325 can be suppressed, thereby preventing displacement from the intended insertion position. Furthermore, the infusion line 21A can be prevented from becoming dislodged from the inferior petrosal sinus 42 and the cerebellopontine angle cistern 43 during fluid injection, and the drainage line 22 can be prevented from becoming dislodged from the inferior petrosal sinus 42 and the cerebellopontine angle cistern 43 during fluid drainage. This allows the infusion line 21A to more reliably inject fluid into the cerebellopontine angle cistern 43. The drainage line 22 can more reliably drain fluid from the cerebellopontine angle cistern 43.

[0071] 3 and 4, the guiding catheter 32 has a bending portion 324. The bending portion 324 is provided in a portion including the tip portion 321 of the guiding catheter 32, and is bent in a direction intersecting the direction of the longitudinal axis 325 of the guiding catheter 32. As shown in Fig. 4, a distance L1 between the tip portion 321 at the bending portion 324 and the longitudinal axis 325 of the guiding catheter 32 in a direction perpendicular to the direction of the longitudinal axis 325 of the guiding catheter 32 is longer than an outer diameter D1 of the fixing member 35 in the maximally expanded state. The maximally expanded state of the fixing member 35 refers to a state in which the fixing member 35 is released from constraint and naturally expanded to its maximal extent.

[0072] Furthermore, the length L2 of the portion of the guiding catheter 32 extending further toward the insertion side than the second end 354 on the insertion side of the fixing member 35 is longer than the outer diameter D1 of the fixing member 35 in the maximum expanded state.

[0073] According to the catheter device 3 of this embodiment, the bending portion 324 is bent in a direction intersecting the longitudinal axis 325 of the guiding catheter 32, and therefore is not parallel to the longitudinal axis 325 of the guiding catheter 32 inside the blood vessel. Therefore, the inner wall of the inferior petrosal sinus 42 and the inner wall of the blood vessel are located on an extension line of the tip portion 321 of the guiding catheter 32. This allows a medical instrument such as a needle guided by the guiding catheter 32 to reliably come into contact with the inner wall of the inferior petrosal sinus 42 and the inner wall of the blood vessel.

[0074] In a direction perpendicular to the longitudinal axis 325 of the guiding catheter 32, a distance L1 between the tip end 321 at the bending portion 324 and the longitudinal axis 325 of the guiding catheter 32 is longer than the outer diameter D1 of the fixing member 35 in the maximum expanded state. Therefore, the tip end 321 of the guiding catheter 32 can reliably contact the inner wall of the inferior petrosal sinus 42 and the inner wall of the blood vessel. Therefore, a medical instrument such as a needle guided by the guiding catheter 32 can more reliably contact the inner wall of the inferior petrosal sinus 42 and the inner wall of the blood vessel. As a result, the catheter device 3 according to this embodiment can be easily positioned relative to a biological site located near the blood vessel from inside the blood vessel, thereby more reliably accessing the biological site.

[0075] Furthermore, the guiding sheath 31 has an internal space capable of accommodating the guiding catheter 32 and the fixing member 35, and therefore the guiding catheter 32 and the fixing member 35 can be guided to the vicinity of a biological site (the cerebellopontine angle cistern 43 in the example shown in FIG. 3 ) while they are housed within the internal space. When the fixing member 35 comes out of the internal space of the guiding sheath 31, it expands due to its own self-expanding function and is positioned inside a blood vessel near the biological site. When the bending portion 324 of the guiding catheter 32 comes out of the internal space of the guiding sheath 31, it bends in a direction intersecting the direction of the longitudinal axis 325 of the guiding catheter 32 near the biological site. As a result, the catheter device 3 according to this embodiment can more reliably guide the guiding catheter 32 and the fixing member 35 to the vicinity of the biological site using the guiding sheath 31, thereby more reliably accessing a biological site located near the blood vessel from inside the blood vessel.

[0076] As described above, the length L2 of the portion of the guiding catheter 32 extending beyond the second end 354 on the insertion side of the fixing member 35 is longer than the outer diameter D1 of the fixing member 35 in the maximum expanded state. Therefore, regardless of the course and inner diameter of the blood vessel, the tip end 321 of the guiding catheter 32 can reliably contact the inner wall of the inferior petrosal sinus 42 and the inner wall of the blood vessel. Therefore, a medical instrument such as a needle guided by the guiding catheter 32 can more reliably contact the inner wall of the inferior petrosal sinus 42 and the inner wall of the blood vessel. This allows the catheter device 3 according to this embodiment to more reliably access a body part located near the blood vessel from inside the blood vessel.

[0077] 4, the guiding catheter 32 has a contrast marker 326 provided at the tip portion 321. This allows the surgeon to confirm the position of the tip portion 321 of the guiding catheter 32 under X-ray fluoroscopy when the guiding catheter 32 accesses a living body part.

[0078] Furthermore, the guiding catheter 32, the guiding sheath 31, and the drainage catheter 33 can all be operated independently of one another. Therefore, the surgeon can independently operate the guiding catheter 32, the guiding sheath 31, and the drainage catheter 33 according to the course and inner diameter of the blood vessel, thereby enabling the catheter device 3 according to this embodiment to more reliably access a living body part located near the blood vessel from inside the blood vessel.

[0079] Fig. 5 is a schematic diagram illustrating the connection structure of the fixing member to the guiding catheter. Fig. 6 is a schematic diagram illustrating the state of the bent portion of this embodiment depending on the state of the blood vessel. Fig. 6(a) is a schematic diagram illustrating a state where the inner diameter D11 of the blood vessel 71 is relatively large. Fig. 6(b) is a schematic diagram illustrating a state where the inner diameter D12 of the blood vessel 71 is relatively medium. Fig. 6(c) is a schematic diagram illustrating a state where the inner diameter D13 of the blood vessel 71 is relatively small.

[0080] The catheter device 3 according to this embodiment will be described with reference to FIG. 5 . For ease of explanation, FIG. 5 illustrates the bending portion 324 of the guiding catheter 32 in an unbent state. As shown in FIG. 5 , the fixing member 35 of the catheter device 3 according to this embodiment is connected and fixed to the outer circumferential surface of the guiding catheter 32 only at the first end 353 on the proximal side, and is not fixed to the guiding catheter 32 at the second end 354 on the insertion side. Therefore, as indicated by arrow A23 in FIG. 5 , the portion of the guiding catheter 32 present inside the cylindrical fixing member 35 can move or deform. That is, the portion of the guiding catheter 32 present inside the cylindrical fixing member 35 can be freely positioned within the cylindrical fixing member 35. Furthermore, as indicated by arrows A21 and A22 in FIG. 5 , the portion of the guiding catheter 32 extending further toward the insertion side than the second end 354 of the fixing member 35 has a high degree of freedom in positioning. That is, the distal end 321 of the guiding catheter 32 has a high degree of freedom in positioning.

[0081] This allows the distal end 321 of the guiding catheter 32 to be positioned toward the inner wall of the blood vessel and to be deformed in a more natural manner. That is, when the distal end 321 of the guiding catheter 32 abuts against the target position on the inner wall of the blood vessel, less external force is applied to the guiding catheter 32, thereby reducing the load on the entire catheter device 3 and the living body, such as the blood vessel. As described above with reference to FIGS. 3 and 4 , the distance L1 between the distal end 321 at the bending portion 324 and the longitudinal axis 325 of the guiding catheter 32 in the direction perpendicular to the longitudinal axis 325 of the guiding catheter 32 is longer than the outer diameter D1 of the fixing member 35 in the maximum expanded state. Therefore, the distal end 321 of the guiding catheter 32 can be positioned toward the inner wall of the blood vessel and to be deformed while suppressing changes in the direction (i.e., angle) of the distal end 321 of the guiding catheter 32, regardless of the expanded state of the fixing member 35.

[0082] For example, as shown by arrow A26 in Fig. 6(a), when the inner diameter D11 of the blood vessel 71 is relatively large, the distal end 321 of the guiding catheter 32 can be positioned so as to face approximately perpendicular to the inner wall of the blood vessel 71. As shown by arrow A27 in Fig. 6(b), when the inner diameter D12 of the blood vessel 71 is relatively medium, the distal end 321 of the guiding catheter 32 can be positioned so as to face the inner wall of the blood vessel so that an acute angle is formed between an extension of the distal end 321 and the inner wall of the blood vessel 71. Furthermore, as shown by arrow A28 in Fig. 6(c), when the inner diameter D13 of the blood vessel 71 is relatively small, the distal end 321 of the guiding catheter 32 can be positioned so as to face the inner wall of the blood vessel so that an even acute angle is formed between an extension of the distal end 321 and the inner wall of the blood vessel 71. 6(c), the stability of positioning can be improved by the bending portion 324 coming into contact with the inner wall of the blood vessel opposite the position of the tip portion 321. In this way, the catheter device 3 according to this embodiment can accommodate various blood vessels having different courses and inner diameters.

[0083] Figures 7 to 10 are schematic diagrams illustrating the relationship between the guiding catheter and the needle. Figure 9(a) is a schematic diagram illustrating the state immediately after the needle is inserted into the lumen of the guiding catheter. Figure 9(b) is a schematic diagram illustrating the rotation of the needle in the lumen of the guiding catheter. Figure 10(a) is a schematic diagram illustrating the position adjustment of the puncture portion of the needle in the lumen of the guiding catheter. Figure 10(b) is a schematic diagram illustrating the state after the puncture portion of the needle has passed through the lumen of the guiding catheter.

[0084] The catheter device 3 according to this embodiment may have a needle 53. The needle 53 according to this embodiment is an example of the "medical instrument" of the present invention and is capable of accessing a living body site. For example, as shown in FIGS. 7 and 9(a), the needle 53 is insertable into the lumen of the drainage catheter 33. In other words, the drainage catheter 33 has a lumen through which the needle 53 can be inserted. As shown in FIG. 8, the needle 53 has an elongated wire 532 and a puncture portion 533. The puncture portion 533 is provided at the end of the wire 532 and has a cutting edge shaped like a lancet point or the like, with an oblique cutting surface 534.

[0085] Here, the drainage catheter 33 and the needle 53 according to this embodiment will be described with reference to FIG. 7 . The bending modulus of the wire of the needle 53 according to this embodiment is smaller than that of the guiding catheter 32. Furthermore, the bending modulus of the drainage catheter 33 according to this embodiment is smaller than that of the guiding catheter 32. Therefore, even if the shape of the bent portion 324 of the guiding catheter 32 changes depending on the course of the blood vessel and the inner diameter of the blood vessel, the wire 532 of the needle 53 deforms to fit the shape of the bent portion 324 of the guiding catheter 32. Therefore, as shown in FIG. 7 , it is possible to prevent the position of the tip portion 321 of the guiding catheter 32 from shifting from the predetermined position P1 due to the wire 532 of the needle 53 being inserted into the lumen of the drainage catheter 33. This allows the puncture portion 533 provided at the end of the wire 532 of the needle 53 to more reliably puncture the targeted position. By suppressing misalignment of the puncture position, the risk of damaging biological tissue different from what was intended due to mispuncture is reduced, and the need to redo the puncture operation due to misalignment is eliminated. Note that the flexural modulus of the guiding catheter 32 may be made higher than that of the needle 53 and the discharge catheter 33 by using a braided catheter for the guiding catheter 32 or by making the lumen wall thicker.

[0086] 8, the wire 532 in the vicinity of the puncture portion 533 has a curved shape similar to the curved portion 324 of the guiding catheter 32. Here, as shown in Fig. 8, the blade surface 534 formed on the cutting edge of the puncture portion 533 faces outward from the curve. This allows the puncture portion 533 to puncture the blood vessel wall at an angle closer to perpendicular.

[0087] 9( a), when the needle 53 is inserted into the lumen of the discharge catheter 33 with the blade surface 534 facing the inside of the curve and passes through the lumen of the guiding catheter 32, the wire 532 of the needle 53 rotates in the lumen of the discharge catheter 33 and the lumen of the guiding catheter 32, as indicated by arrow A31 in FIG. 9( b), and the curved shape of the wire 532 matches the shape of the bent portion 324 of the guiding catheter 32. As a result, the blade surface 534 of the puncture portion 533 faces the outside of the curve.

[0088] 10(a), the surgeon can rotate the proximal portion of the wire 532 to transmit the rotational force of the wire 532 to the puncture portion 533. That is, when the surgeon rotates the proximal portion of the wire 532 as shown by arrow A32 in FIG. 10(a), the puncture portion 533, which receives the rotational force of the wire 532, rotates as shown by arrow A33 in FIG. 10(a). This allows the surgeon to fine-tune the orientation of the blade surface 534 of the puncture portion 533 and the position of the puncture portion 533 in the lumen of the drainage catheter 33 and the lumen of the guiding catheter 32. This allows the puncture portion 533 of the needle 53 to more reliably puncture the targeted position, as shown in FIG. 10(b).

[0089] Figure 11 is a schematic diagram showing a fixing member of this embodiment. Figure 11(a) is a schematic diagram showing a fixing member disposed inside a blood vessel. Figure 11(b) is a schematic diagram showing a first specific example of a fixing member of this embodiment as viewed from the longitudinal axis direction of the guiding catheter 32. Figure 11(c) is a schematic diagram showing a second specific example of a fixing member of this embodiment as viewed from the longitudinal axis direction of the guiding catheter 32.

[0090] The fixing member 35 has a plurality of struts 355 formed as thin, linear wires, and is formed into a cylindrical skeleton as a whole. The fixing member 35 has a structure that does not block the blood flow (see arrow A35 shown in FIG. 11( a)) inside the blood vessel 71. Note that the fixing member 35 in this embodiment may be made of braided metal wires, or may be cut out from a tubular metal.

[0091] 11( a), the fixing member 35 has a first portion 356 and a second portion 357. The first portion 356 is a portion having a constant diameter in the direction of the longitudinal axis 325 of the guiding catheter 32. The second portion 357 is a portion having a gradually decreasing diameter in the direction of the longitudinal axis 325 of the guiding catheter 32. Specifically, the diameter of the second portion 357 gradually decreases from the insertion side toward the proximal side.

[0092] The second portion 357 has a first tapered portion 357a and a second tapered portion 357b. The first tapered portion 357a is located on the insertion side of the second portion 357 and is connected to the first portion 356. The second tapered portion 357b is located on the proximal side of the second portion 357 and is connected to the first end portion 353. In other words, the second tapered portion 357b is connected and fixed to the outer periphery of the guiding catheter 32 at the proximal end as the first end portion 353.

[0093] As shown in FIG. 11A , the spacing between adjacent struts 355 in the second portion 357 is wider than the spacing between adjacent struts 355 in the first portion 356. For example, in a first specific example of a fixing member 35C shown in FIG. 11B , the first portion 356 has 16 struts 355 a in the circumferential direction. The first tapered portion 357 a of the second portion 357 has 8 struts 355 b in the circumferential direction. The second tapered portion 357 b of the second portion 357 has 4 struts 355 c in the circumferential direction. Furthermore, in a second specific example of a fixing member 35D shown in FIG. 11C , the first portion 356 has 12 struts 355 a in the circumferential direction. The first tapered portion 357 a of the second portion 357 has 6 struts 355 b in the circumferential direction. The second tapered portion 357b of the second portion 357 has three struts 355c in the circumferential direction.

[0094] Thus, the number of struts 355 in second tapered portion 357b of second portion 357 is fewer than the number of struts 355 in first portion 356 and the number of struts 355 in first tapered portion 357a of second portion 357. Furthermore, the number of struts 355 in first tapered portion 357a of second portion 357 is fewer than the number of struts 355 in first portion 356. Therefore, the distance between adjacent struts 355 in second tapered portion 357b of second portion 357 is wider than the distance between adjacent struts 355 in first portion 356 and the distance between adjacent struts 355 in first tapered portion 357a of second portion 357. Furthermore, the distance between adjacent struts 355 in the first tapered portion 357a of the second portion 357 is wider than the distance between adjacent struts 355 in the first portion 356. The number of struts 355 in the second portion 357 is not particularly limited as long as the number allows the fixing member 35 to be stably held relative to the guiding catheter 32.

[0095] This prevents the blood flow in the blood vessel 71 from being blocked by the struts 355 of the fixing member 35, even when the fixing member 35 is deployed and the catheter device 3 is indwelled. Furthermore, the number of struts 355 in the second portion 357 that intersects with the blood flow direction in the blood vessel 71 where the fixing member 35 is placed gradually decreases, thereby preventing the struts 355 from interfering with blood components and causing thrombus formation. Meanwhile, the first portion 356, which has a constant diameter in the direction of the longitudinal axis 325 of the guiding catheter 32, abuts against the inner wall of the blood vessel 71, similar to a typical stent, and thus fixes the relative position of the guiding catheter 32 with the catheter device 3. Therefore, the fixing member 35 can maintain close contact and fixation with the inner wall of the blood vessel 71 in the first portion 356 having a constant diameter, while preventing thrombus formation in the second portion 357 that intersects with the blood flow.

[0096] Next, specific examples of the drainage catheter and needle of this embodiment will be described with reference to the drawings. Note that, where the components of the drainage catheter and needle of this example are similar to those of the drainage catheter and needle described above with reference to Figures 7 to 10, redundant description will be omitted where appropriate, and the following description will focus on the differences.

[0097] Figure 12 is a schematic diagram showing an evacuation catheter and a needle according to a first example. Figure 12(a) is a schematic diagram showing the state before the needle is inserted into the blood vessel. Figure 12(b) is a schematic diagram showing the state after the needle has inserted into the blood vessel. Figure 12(c) is a schematic diagram showing the state after the needle has penetrated the blood vessel. Figure 12(d) is a schematic diagram showing the state after the evacuation catheter and the needle have penetrated the blood vessel.

[0098] The discharge catheter 33A of this example is formed of a flexible tube and has a radiopaque marker 332. The radiopaque marker 332 is provided at a tip portion 331 of the discharge catheter 33A.

[0099] 12A, before the needle 53A is inserted into the blood vessel 71, the wire 532 and the puncture portion 533 are housed in the lumen of the discharge catheter 33A. The puncture portion 533 is provided with the radiopaque marker 535.

[0100] 12(b), when the tip 331 of the discharge catheter 33A advances inside the blood vessel 71 and comes into contact with the inner wall of the blood vessel 71, the discharge catheter 33A cannot advance further than the inner wall of the blood vessel 71. At this time, the discharge catheter 33A is flexible, and a space exists between the inner wall of the discharge catheter 33A and the wire 532 of the needle 53A, so the discharge catheter 33A bends. This reduces the apparent length of the discharge catheter 33A. Therefore, the tip of the puncture portion 533 of the needle 53A is exposed from the lumen of the discharge catheter 33A and punctures the blood vessel 71.

[0101] 12(c), when the puncture portion 533 further advances and penetrates the blood vessel 71, the discharge catheter 33A enters the hole formed by the puncture portion 533, following the puncture portion 533 due to a repulsive force (i.e., elastic force) that returns the deflection to its original state. At this time, the radiopaque marker 535 of the needle 53A is positioned at a predetermined position relative to the discharge catheter 33A. Specifically, as shown in FIG. 12(c), the position of the radiopaque marker 535 of the needle 53A coincides with the position of the radiopaque marker 332 of the discharge catheter 33A in the direction of the longitudinal axes of the discharge catheter 33A and the wire 532 of the needle 53A. This allows the surgeon to confirm, under X-ray fluoroscopy, the appropriate length at which the tip of the puncture portion 533 is exposed from the lumen of the discharge catheter 33A.

[0102] 12(d), when the discharge catheter 33A is further advanced and penetrates the blood vessel 71, the deflection of the discharge catheter 33A is released. As a result, the puncture portion 533 is housed in the lumen of the discharge catheter 33A. This causes the discharge catheter 33A and the needle 53A to return to their original state before the discharge catheter 33A was inserted into the blood vessel 71.

[0103] According to this example, the tip of the puncture part 533 of the needle 53A is housed and protected within the lumen of the discharge catheter 33A except when the puncture part 533 of the needle 53A is inserted into the blood vessel 71. This reduces the risk of damaging the catheter device 3 according to this embodiment and biological tissue such as the blood vessel 71.

[0104] Figure 13 is a schematic diagram showing a drainage catheter and a needle according to a second example. Figure 13(a) is a schematic diagram showing the state before the needle is inserted into the blood vessel. Figure 13(b) is a schematic diagram showing the state when the needle is inserted into the blood vessel. Figure 13(c) is a schematic diagram showing the state after the needle has inserted into the blood vessel.

[0105] The discharge catheter 33B of this example has a radiopaque marker 332B. The radiopaque marker 332B is provided at the distal end 331 of the discharge catheter 33B, and has a female thread 336 formed therein.

[0106] The needle 53B of this example has a wire 532 and a puncture portion 533B. The puncture portion 533B has a male thread 536 formed on its outer circumferential surface. As shown in Figure 13(a) , before the needle 53B is inserted into the blood vessel 71 (see Figure 12(a) , etc.), the wire 532 and the puncture portion 533B are housed in the lumen of the drainage catheter 33B.

[0107] As shown by arrow A37 in Figure 13(b), when the surgeon inserts the puncture portion 533B into the blood vessel 71, the surgeon advances the puncture portion 533B through the lumen of the discharge catheter 33B via the wire 532 and rotates the wire 532 clockwise around its longitudinal axis, causing the male thread 536 of the puncture portion 533B to engage with the female thread 336 of the radiopaque marker 332B. This fixes the puncture portion 533B of the needle 53B to the tip portion 331 of the discharge catheter 33B. The tip portion of the puncture portion 533B is exposed from the lumen of the discharge catheter 33B.

[0108] 13(c), after the discharge catheter 33B and needle 53B have been inserted into the blood vessel 71, the surgeon rotates the wire 532 counterclockwise around the longitudinal axis of the wire 532, causing the male thread 536 of the puncture portion 533B to disengage from the female thread 336 of the radiopaque marker 332B. This allows the surgeon to separate the needle 53B from the discharge catheter 33B and remove only the needle 53B.

[0109] According to this example, the surgeon can stably set an appropriate length for the tip of the puncture portion 533B to be exposed from the lumen of the discharge catheter 33B. Furthermore, the tip of the puncture portion 533B is housed and protected within the lumen of the discharge catheter 33B except when the puncture portion 533B of the needle 53B is inserted into the blood vessel 71. Therefore, the same effects as those described above with reference to Figures 12(a) to 12(d) can be obtained.

[0110] 14A and 14B are schematic diagrams showing a drainage catheter and a needle according to a third example, with Fig. 14A being a schematic diagram showing the state before the needle is inserted into the blood vessel, and Fig. 14B being a schematic diagram showing the state when the needle is inserted into the blood vessel.

[0111] The drainage catheter 33C of this example has a magnet 332C. The magnet 332C is attached to the distal end 331 of the drainage catheter 33C and has a north pole 334a and a south pole 334b. In the drainage catheter 33C of this example, the north pole 334a is located more inward than the south pole 334b, and the south pole 334b ​​is located more outward than the north pole 334a.

[0112] Needle 53C of this specific example has wire 532, puncture portion 533C, and magnet 537. As shown in Figure 14(a) , before needle 53C is inserted into blood vessel 71 (see Figure 12(a) , etc.), wire 532 and puncture portion 533C are housed in the lumen of drainage catheter 33C. Magnet 537 is provided in puncture portion 533C and has a north pole 538a and a south pole 538b. In needle 53C of this specific example, south pole 538b is provided inside north pole 538a, and north pole 538a is provided outside south pole 538b.

[0113] As shown in arrow A41 in Fig. 14(b), when the surgeon inserts puncture portion 533C into blood vessel 71, puncture portion 533C is pushed forward within the lumen of drainage catheter 33C via wire 532. Then, as shown in arrow A42 in Fig. 14(b), N pole 538a of magnet 537 and N pole 334a of magnet 332C repel each other, generating a repulsive force in a direction that pushes needle 53C back toward the operator.

[0114] In this state, when the surgeon pushes the puncture portion 533C through the lumen of the discharge catheter 33C via the wire 532, the proximal portion of the wire 532 begins to bend. The length of the tip of the puncture portion 533C exposed from the lumen of the discharge catheter 33C at this time is set to an appropriate length for exposure from the lumen of the discharge catheter 33C at the time of puncture. In this state, the surgeon pushes the discharge catheter 33C and the needle 53C (specifically, the wire 532) forward while fixing the proximal portions thereof, and punctures the puncture portion 533C into the blood vessel 71.

[0115] After the discharge catheter 33C and needle 53C have been inserted into the blood vessel 71, when the surgeon releases the proximal portions of the discharge catheter 33C and needle 53C, the needle 53C is automatically pushed back toward the proximal side by a repulsive force in the direction of arrow A42, allowing the surgeon to remove only the needle 53C.

[0116] According to this specific example, the surgeon can use magnets 332C and 537 to stably set an appropriate length for the tip of puncture portion 533C to be exposed from the lumen of drainage catheter 33C. Furthermore, except when puncture portion 533C of needle 53C is inserted into blood vessel 71, the tip of puncture portion 533C is housed and protected within the lumen of drainage catheter 33C. Therefore, the same effects as those described above with reference to FIGS. 12( a) to 12(d) can be obtained. In this specific example, the north poles of the magnets of drainage catheter 33C and needle 53C repel each other, generating a repulsive force that pushes needle 53C back toward the operator. However, the magnets may be arranged in opposite directions, and the repulsive force generated by the repulsion of their south poles may be utilized.

[0117] The above describes an embodiment of the present invention. However, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the claims. The configurations of the above embodiment can be partially omitted or arbitrarily combined differently. In the description of FIGS. 5 to 14, a case was given in which needles 53, 53A, 53B, and 53C puncture blood vessel 71. However, as described above with reference to FIGS. 3 and 4, needles 53, 53A, 53B, and 53C may puncture not only blood vessel 71 but also dura mater 46 and arachnoid mater 47. Even in this case, the same effects as those described above with reference to FIGS. 5 to 14 can be obtained.

[0118] 2: Liquid circulation system, 2A: Liquid circulation system, 3: Catheter device, 3A: Catheter device, 21: Infusion line, 21A: Infusion line, 22: Drain line, 23: Liquid supply section, 24: Oxygenation mechanism, 25: Oxygen supply source, 26: Heat exchanger, 31: Guiding sheath, 32: Guiding catheter, 33: Drain catheter, 33A: Drain catheter, 33B: Drain catheter, 33C: Drain catheter, 34: Infusion catheter, 35: Fixing member, 35C: Fixing member, 35D: Fixing member, 36: Connector, 41: Internal jugular vein, 42: Inferior petrosal sinus, 43: Cerebellopontine angle cistern, 44: Jugular bulb, 45: Brainstem, 46: Dura mater, 47: Arachnoid mater, 48: Skin, 49: Exterior, 53: Needle, 53A: Needle, 53B: Needle, 53C: Needle, 71: Blood vessel, 271: First tube, 272: Second tube, 273: Third tube, 311: Tip portion, 321: Tip portion, 324: Bending portion, 325: Longitudinal axis, 326: Radiopaque marker, 331: Tip portion, 332: Radiopaque marker, 332B: Radiopaque marker, 332C: Magnet, 333: Base end portion, 334a: North pole, 334b: South pole, 336: Internal thread, 353: First end portion, 354: Second end portion, 355: Strut, 355a: Strut, 355b: Strut, 355c: Strut, 356: First portion, 357: Second portion, 357a: First tapered portion, 357b: Second tapered portion, 411: Joint portion, 532: Wire, 533: Puncture portion, 533B: Puncture portion, 533C: Puncture portion, 534: Blade surface, 535: Contrast marker, 536: Male screw, 537: Magnet, 538a: North pole, 538b: South pole

Claims

1. A catheter device for accessing a biological site located near a blood vessel from inside the blood vessel, comprising: a long first shaft having an inner cavity that connects a first opening formed at a proximal end with a second opening formed at an insertion end; and a self-expandable fixing member arranged on the outer surface of the first shaft, wherein the first shaft has a bent portion that is provided in a portion that includes the insertion end and is bent in a direction that intersects with the longitudinal axis of the first shaft, and the distance between the insertion end at the bent portion and the longitudinal axis in a direction perpendicular to the longitudinal axis is longer than the outer diameter of the fixing member in its maximum expanded state.

2. The catheter device according to claim 1, further comprising an elongated second shaft having an internal space capable of accommodating the first shaft and the fixing member.

3. The catheter device according to claim 1, further comprising a catheter that can be inserted into the lumen of the first shaft.

4. The catheter device according to claim 3, wherein the catheter has a contrast marker provided at the end on the insertion side.

5. The catheter device according to claim 3, further comprising a medical instrument that can access the biological site, wherein the catheter has a lumen through which the medical instrument can be inserted.

6. The catheter device according to claim 5, characterized in that the medical instrument has a long wire and a puncture portion provided at the end of the wire, and the bending modulus of the wire is smaller than the bending modulus of the first shaft.

7. The catheter device according to claim 6, characterized in that the medical instrument has a contrast marker provided at the puncture portion, and the contrast marker is positioned at a predetermined position relative to the catheter when at least a portion of the puncture portion is exposed from the lumen of the catheter when the puncture portion punctures the biological site.

8. A catheter device as described in claim 1, characterized in that the fixing member is connected to the outer surface of the first shaft only at the first end on the hand side, and is not fixed to the first shaft at the second end on the insertion side.

9. A catheter device as described in claim 1, characterized in that the length of the portion of the first shaft extending toward the insertion side beyond the second end of the fixing member on the insertion side is longer than the outer diameter.

10. The catheter device according to claim 1, wherein the first shaft has a contrast marker provided at the end on the insertion side.

11. The catheter device according to claim 1, wherein the fixing member has a plurality of struts and has a structure that does not block blood flow inside the blood vessel.

12. A catheter device as described in claim 11, characterized in that the fixing member has a first portion having a constant diameter in the direction of the longitudinal axis and a second portion having a diameter that gradually decreases in the direction of the longitudinal axis, and the spacing between adjacent struts in the second portion is wider than the spacing between adjacent struts in the first portion.

13. The catheter device according to claim 1, further comprising: an elongated second shaft having an internal space capable of accommodating the first shaft and the fixing member; and a catheter that can be inserted into the inner cavity of the first shaft, wherein the first shaft, the second shaft, and the catheter can all be operated independently of one another.

Images