WO2014128881A1

WO2014128881A1 - Medical apparatus

Info

Publication number: WO2014128881A1
Application number: PCT/JP2013/054338
Authority: WO
Inventors: 栗田朋香; 谷田部輝幸
Original assignee: テルモ株式会社
Priority date: 2013-02-21
Filing date: 2013-02-21
Publication date: 2014-08-28

Abstract

Provided is a highly safe medical apparatus having a catheter which is to be inserted into a non-lumenous area of biological tissue so as to deliver a substance into the biological tissue, such that backflow of the substance along the outer surface of the catheter is suppressed with as little damage as possible to the biological tissue, and displacement and slipping of the catheter is suppressed. The medical apparatus (1) is inserted into a non-lumenous area of biological tissue in order to deliver a substance into the biological tissue and comprises a catheter (10). The catheter has a longitudinally-extending tube portion (20) and an expanding portion (30) expandable outwardly in a radial direction of the tube portion (20), the expanding portion (30) being formed on the outer surface of the tube portion (20) and extending from the leading end of the tube portion (20) towards the base end of the same at a length of 30% or more of the insertable length (L) of the tube portion (20) with respect to the biological tissue. In the catheter, a delivery lumen (21) for delivering the substance and an expanding lumen (22) for allowing flow of a fluid for expanding the expanding portion (30) inwardly of the expanding portion (30) are formed.

Description

Medical instruments

The present invention relates to a medical device used for continuous convection-enhanced delivery of a substance into a living tissue, particularly for continuous administration of a therapeutic substance into the brain parenchyma.

In recent years, for malignant glioma (glioblastoma, anaplastic astrocytoma, etc.), in addition to surgical therapy and radiation therapy, various therapies such as chemotherapy, immunotherapy, gene therapy, molecular target therapy, etc. Attempts have been made to improve the outcome of malignant brain tumors, including glioma. However, the most malignant glioblastoma has a low 5-year survival rate of about 7%, and still has the poorest prognosis among all cancers (Non-patent Document 1).

The basis of treatment for malignant glioblastoma is as much as possible removal of the tumor by surgery. However, because the brain performs various functions depending on the region, it is often impossible to remove the tumor sufficiently. In particular, in malignant glioblastoma, since tumor cells infiltrate the surrounding brain tissue, total excision at the tissue level is impossible. Therefore, radiotherapy and chemotherapy are indispensable as postoperative adjuvant therapy to improve the treatment outcome of malignant glioblastoma.

Despite the proven effectiveness of chemotherapy for malignant glioma, the therapeutic effect is still not sufficient. In brain tumors, when a therapeutic drug is administered intravenously, the therapeutic drug is permeated through the blood brain barrier (BBB), so there is an inherent problem of permeability, and applicable drugs are limited. . Furthermore, even if BBB permeability is obtained, the drug dosage is limited due to concerns about side effects to the whole body caused by the drug, and an effective drug concentration cannot be ensured at the tumor site.

A convection-enhanced delivery (CED) method has been devised as a new drug administration method for overcoming the problems of chemotherapy for malignant glioma as described above (see, for example, Patent Document 1). ). The CED method is local chemotherapy in which a drug is actively infused from a catheter placed stereotaxically in the brain parenchyma using a microinfusion pump. In the conventional local administration technique to the central nervous system, the distribution of the drug depends on the diffusion of the substance, whether it is intracavitary administration to the tumor excision cavity or a local chemotherapeutic agent placed in the brain. The diffusion of substances is defined by concentration gradients and tissue properties, and even a low-molecular compound with good diffusivity is considered to have a range of only a few millimeters due to absorption and metabolism in capillaries. This is inadequate for 80-90% of recurrences of malignant gliomas occurring at sites within 2 cm from the initial lesion (see Non-Patent Document 2). On the other hand, in the CED method, the pressure gradient during the injection is maintained to induce a bulk flow between the cerebral layers to enhance the diffusion of the injected substance. Therefore, compared with the conventional local administration method, the drug can be distributed more uniformly and at a high concentration over a wide range. In addition, the distribution of the drug in the brain can be controlled by the injection volume and the injection speed, and it is possible to reduce the dose compared to the systemic administration by vein, so that systemic side effects can be suppressed to a level where there is no problem. Is possible. There are a wide variety of drugs that can be administered by the CED method, and various drugs have been tried in rat brain tumor transplantation models, and their effectiveness has been reported. Because of these advantages, the CED method is expected as a treatment method for not only brain tumors but also Parkinson's disease, Alzheimer's disease and epilepsy.

However, there are still some problems to apply CED method widely to clinical application. One is backflow of drugs that occurs along the outer surface of a catheter placed in the brain (in the brain parenchyma). Backflow along the catheter is more likely to occur as the diameter of the catheter tip is larger and the administration rate is faster. For this reason, the diameter of the catheter in the CED method is small, and the injection rate of the drug is very low, 0.5 to 10 μl / min. Therefore, in order to obtain a therapeutically effective amount, it must be administered for a long time, and in some cases, infusion over several days is required. During this time, not only is the patient's freedom restricted for a long period of time, but there is also a risk that the distal end position of the catheter is displaced by the patient's body movement or the catheter is pulled out. These are not preferable because they cause side effects due to administration to unnecessary sites, damage to brain tissue, and complications such as infection (see Non-Patent Document 3). In the CED method, once the drug flows backward and leaks into the brain surface, cerebral sulcus, excision cavity, etc., it becomes difficult to maintain the pressure gradient, and further diffusion cannot be expected. Therefore, in order to realize a more accurate, safe and effective CED method, it is desired to provide a catheter capable of preventing drug backflow.

For example, Patent Document 1 discloses a cannula having a step structure with an outer diameter changing near the end and a drug delivery system as a catheter for preventing a drug backflow. In this technique, a drug having a substantially constant inner diameter is provided with a multi-stage structure in which the outer diameter decreases from the proximal end to the distal end, thereby preventing backflow of the drug.

US Patent Application Publication No. 2007/0088295

However, in the cannula (catheter) described in Patent Document 1, it is necessary to make the outer diameter thicker than the inner diameter because of the necessity of providing a stepped portion. Moreover, since the outer diameter of the cannula is increased at each step portion from the distal end portion to the proximal end portion, the puncture resistance of the cannula is increased at the step portion. Furthermore, since the outer diameter decreases from the proximal end portion to the distal end portion, the catheter can be easily removed. These can cause brain tissue damage, administration to unnecessary sites, infections, and the like.

The present invention solves the above-mentioned problems, and damages the living tissue as much as possible by causing the backflow of the material along the outer surface of the catheter to be passed through the non-lumen region of the living tissue and delivering the material into the living tissue. It is an object of the present invention to provide a highly safe medical device that can be suppressed without any movement, and that suppresses the movement and removal of the catheter.

A medical instrument according to the present invention that achieves the above object is a medical instrument for inserting a substance into a non-luminal region of a living tissue and delivering a substance into the living tissue, and a tubular portion extending in a long length, and The diameter of the tubular portion is formed on the outer periphery of the tubular portion so as to extend from the distal end portion to the proximal end side with a length that is 30% or more of the length of the tubular portion that can be inserted into the living tissue. An extension portion that expands outward in the direction is formed, and a delivery lumen for delivering the substance and an extension lumen for flowing a fluid for expanding the extension portion into the extension portion are formed. Has a catheter.

The medical device configured as described above can increase the outer diameter by expanding the expansion portion in a wide region including the distal end portion of the catheter at the time of administration / delivery of the substance. While suppressing the damage of the living tissue as much as possible without increasing the gap between the catheter and the living tissue after insertion of the catheter, the gap between the catheter and the living tissue is eliminated by expanding the expanded portion, and the catheter is brought into close contact with the tissue in a wide range. The backflow of the delivered substance can be suppressed. Furthermore, the close contact of the catheter with the living tissue also exhibits the effect of preventing the catheter from moving or coming off that may occur during a long indwelling period. In addition, since the outer diameter increases in a wide area of the catheter, the catheter can be in contact with the living tissue over a wide area, the load on the living tissue due to expansion can be dispersed, and the effect of preventing the removal can be further enhanced. , Safety can be improved.

If the expansion part is formed on the entire circumference of the tubular part, the effect of suppressing the back flow of the substance, the effect of preventing the movement and removal of the catheter, and the load on the living tissue due to the expansion are distributed. The effect of making it possible can be further enhanced.

If the expansion portion is formed with a length that is 100% of the insertion length of the tubular portion into the living tissue, the effect of preventing the catheter from moving or coming out can be further enhanced.

The expansion portion is provided on the outer periphery of the tubular portion, and the tubular portion is provided by a fluid flowing in by being provided on the distal end side of the first expansion portion or on the outer periphery of the first expansion portion. If it has the 2nd expansion part which can be expanded to the diameter direction outside, the effect which controls backflow of a substance by the 1st expansion part and the 2nd expansion part, and the movement and removal of a catheter are prevented. The effect of distributing the load on the living tissue due to expansion can be arbitrarily adjusted.

If the second expansion portion expands larger than the first expansion portion outward in the radial direction of the tubular portion at the time of expansion, the backflow of the substance can be effectively suppressed by the second expansion portion.

By further including a core material portion inserted into the delivery lumen or another lumen different from the delivery lumen, even a flexible catheter that is difficult to be inserted into a living tissue can be inserted into a target site with high accuracy. be able to.

If it is used for increased convection delivery of a substance to a tumor, it becomes possible to effectively deliver the substance to the tumor.

If it is used for increased convection delivery of substances to the brain, it becomes possible to effectively deliver substances to the brain.

It is a top view which shows the medical instrument which concerns on 1st Embodiment. It is sectional drawing which shows the catheter of the medical instrument which concerns on 1st Embodiment, (A) is before expanding an expansion part, (B) shows the time of expanding an expansion part. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. It is the schematic which shows the time of administering a therapeutic substance in brain parenchyma with the medical device which concerns on 1st Embodiment. It is sectional drawing which shows the catheter of the medical device which concerns on 2nd Embodiment, (A) is before expanding an expansion part, (B) shows the time of expanding an expansion part. It is sectional drawing which shows the catheter of the medical device which concerns on 3rd Embodiment, (A) is before expanding an expansion part, (B) shows the time of expanding an expansion part. It is sectional drawing which shows the modification of a catheter. FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. It is sectional drawing which shows the other modification of a catheter. It is sectional drawing which shows the other modification of a catheter. It is sectional drawing which shows the other modification of a catheter. It is sectional drawing which shows the other modification of a catheter. It is sectional drawing which shows the other modification of a catheter.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

In the following description, the proximal side of the catheter is referred to as “proximal end side”, and the inserted side is referred to as “distal end side”. Further, the “catheter” represents one including a tube used for medical purposes. The catheter is not limited to treatment, and may be for examination, for example.
<First Embodiment>

The medical device 1 according to the first embodiment is used in a convection-enhanced delivery (CED) method for delivering a therapeutic substance to, for example, a brain tumor in the brain. The CED method is a method in which a therapeutic substance (drug) is injected in small amounts in a stereotaxic manner in the brain parenchyma while being actively and continuously pressurized, thereby maintaining a pressure gradient and convection. It is a local chemotherapy that uses the resulting flow to distribute and distribute a therapeutic substance in a wide and high concentration in the tissue gap.

As shown in FIGS. 1 to 3, the medical instrument 1 has a tubular catheter 10 that is inserted into the brain parenchyma to deliver a therapeutic substance. The catheter 10 has a tubular portion 20 in which a delivery lumen 21 for delivering a therapeutic substance is formed, and a tubular shape disposed on the outer peripheral surface of the tubular portion 20 so as to form a tubular portion 20 and a double tube. And the hub 40 fixed to the proximal end of the tubular portion 20.

The tubular portion 20 is made of a flexible material, and for example, a polyurethane elastomer, a polyamide elastomer, a polyester elastomer, a polyvinyl chloride, a silicone elastomer, or the like can be suitably applied thereto, but is not limited thereto.

The extended portion 30 has a distal end portion joined to the distal end of the tubular portion 20 and a proximal end portion joined to the distal end of the hub 40. An expansion lumen 22 is formed between the expansion portion 30 and the tubular portion 20. When the expansion fluid flows into the expansion lumen 22, the expansion portion 30 is brought into close contact with the tubular portion 20 as shown in FIG. 2 (A) and from the distal end portion to the proximal end portion as shown in FIG. 2 (B). The entire span extends radially outward. The length L of the region of the tubular portion 20 that can be inserted into the living tissue is preferably 40 to 200 mm, but is not limited thereto.

The extended portion 30 is arranged on the entire circumference so as to surround the outer periphery of the tubular portion 20 over substantially the entire region from the distal end portion to the proximal end portion of the tubular portion 20. As a material constituting the expansion lumen 22, it is preferable to use an elastically deformable material. For example, silicone, thermoplastic elastomer, rubber, or the like can be suitably applied. The expansion portion 30 is formed with a length that is approximately 100% of the length L that the tubular portion 20 can be inserted into the living tissue from the distal end portion to the proximal end side of the tubular portion 20. In addition, the length of the expansion part 30 may not be substantially 100% of the insertion length L. The extended portion 30 is provided at least at the distal end portion of the tubular portion 20, and is preferably formed with a length of 30% or more of the insertable length L, more preferably 50% or more of the insertable length L, and more The length is preferably 70% or more of the insertable length L, and most preferably 100% of the insertable length L. In addition, the front-end | tip part of the expansion part 30 does not necessarily need to be provided from the strict tip part of the tubular part 20. Further, the base end portion of the extension portion 30 may be joined to the tubular portion 20 instead of the hub 40.

The hub 40 has a delivery opening 41 that communicates with the delivery lumen 21 and an expansion opening 42 that communicates with the expansion lumen 22. In the delivery opening 41, a connecting pipe 46A provided at an end of a liquid feeding tube 46 extending from a syringe 45 filled with a therapeutic substance can be inserted. The syringe 45 is attached to a microinjection pump 48 (see FIG. 4) or the like, and can supply a therapeutic substance at a predetermined injection amount and injection rate. The delivery opening 41 has a structure in which the connection pipe 46A is directly fitted, but a three-way stopcock or a check valve may be provided between the delivery opening 41 and the connection pipe 46A.

The expansion opening 42 is connected to an expansion tube 44 in which a three-way stopcock 43 is disposed at the end. The three-way cock 43 is for sealing the fluid supplied into the expansion lumen 22 for an arbitrary time. If the fluid can be sealed, the three-way stopcock 43 is not necessarily provided, and for example, a check valve may be provided. The three-way stopcock 43 can be connected to a fluid supply tube 49 connected to an indeflator 47 (see FIG. 4) that can supply an expansion fluid.

The outer diameter D (see FIG. 1) of the portion that is inserted into the living tissue of the catheter 10 before the expansion portion 30 is expanded is preferably 0.1 to 50 mm, but is not limited thereto. The amount of expansion of the catheter 10 in the radial direction (the amount of increase in the radius of the catheter 10) when the expansion unit 30 is expanded is several μm to several mm, but is not limited thereto.

The fluid injected into the expansion lumen 22 is not particularly limited as long as it is a fluid that can expand the expansion portion 30, and is preferably sterilized water, physiological saline, various contrast agents for MRI imaging or X-ray imaging, and the like. Applicable. In particular, when a contrast agent is used, the catheter 10 can be visually recognized by an image diagnostic apparatus such as MRI, X-ray fluoroscopy apparatus, or X-ray CT, so that the insertion position of the catheter 10 can be confirmed. This not only prevents damage to the brain tissue due to movement of the catheter 10, administration to unnecessary sites, infections, etc., but also enables use in combination with real-time monitoring technology for insertion of the catheter 10 and administration of therapeutic substances. It is also very useful from the point of. Real-time monitoring technology is an important technology for accurately and safely implementing the CED method.

The therapeutic substance is, for example, an anticancer agent, more specifically, an alkylating agent such as nimustine, ranimustine, and temozolomide, a platinum preparation such as cisplatin, oxaliplatin, and dahaplatin, sulfazine, methotrexate, fluorouracil, fructocin, azathioprine, pentostatin, etc. Antimetabolite, irinotecan, doxorubicin, topoisomerase inhibitors such as levofloxacin, microtubule depolymerization inhibitor such as paclitaxel, dotaxel, antitumor antibiotics such as doxorubicin, epirubicin, bleomycin, imatinib, gefitinib, sunitinib, cetuximab, cetuximab However, it is not limited to these.
Next, the operation of the medical instrument 1 according to this embodiment will be described.

First, the connection pipe 46A of the liquid feeding tube 46 connected to the syringe 45 filled with the therapeutic substance is fitted into the delivery opening 41 of the hub 40 and connected. Thereafter, the catheter 10 is grasped, and the catheter 10 is inserted into the brain parenchyma until the tip reaches the brain tumor in the brain parenchyma or the vicinity of the brain tumor.

Next, as shown in FIG. 4, a fluid supply tube 49 is connected to the three-way cock 43, and fluid is supplied into the expansion lumen 22 by the indeflator 47 or the like. As a result, the outer diameter of the catheter 10 increases within the brain parenchyma in the range of the insertion length L from the distal end portion of the catheter 10 toward the proximal end side. Next, the three-way stopcock 43 is closed, the fluid injected into the expansion lumen 22 is sealed, and the state where the outer diameter of the catheter 10 is increased is maintained. Even if a check valve is provided instead of the three-way stopcock 43, the state in which the outer diameter of the catheter 10 is increased can be maintained. The state in which the outer diameter of the catheter 10 is increased is continued until the delivery of the therapeutic substance is completed.

Next, a therapeutic substance is supplied from the syringe 45 to the delivery lumen 21 using a microinfusion pump 48 or the like. The connection of the liquid feeding tube 46 to the hub 40 may be performed after the catheter 10 is inserted into the brain parenchyma.

After the delivery of the therapeutic substance is completed, the three-way stopcock 43 is opened, the fluid injected into the expansion lumen 22 is withdrawn, and the expansion portion 30 is elastically contracted by its own elastic force, thereby the outer diameter of the catheter 10 After the decrease, the catheter 10 is removed.

As described above, the medical device 1 according to the first embodiment is for delivering a therapeutic substance (substance) into the brain parenchyma, which is a non-luminal region of a living tissue, and is a tubular tube extending in a long length. The portion 20 and the outer circumference of the tubular portion 20 are formed to extend from the distal end portion to the proximal end side with a length of 30% or more of the length L that can be inserted, and outward in the radial direction of the tubular portion 20. A delivery lumen 21 for delivering a therapeutic substance, and an extension lumen 22 for flowing a fluid for expanding the extension 30 into the extension 30 are formed. A catheter 10. For this reason, since the outer diameter can be increased in a wide region including the distal end portion of the catheter 10 at the time of administration / delivery of the therapeutic substance, damage to the living tissue is minimized without increasing the outer diameter when the catheter 10 is inserted. While suppressing, the gap between the catheter 10 and the living tissue generated after the insertion of the catheter 10 is eliminated by the expansion of the expansion portion 30, and the catheter 10 is brought into close contact with the tissue in a wide range, thereby allowing the therapeutic substance delivered into the brain parenchyma. Backflow can be suppressed. Furthermore, the close contact of the catheter 10 with the living tissue also exhibits an effect of preventing the catheter 10 from moving or coming off that may occur in a long-term indwelling period. In addition, since the outer diameter increases in a wide area of the catheter 10, the catheter 10 can be in contact with the living tissue over a wide area, the load on the living tissue due to expansion can be dispersed, and the effect of preventing the disconnection can be further enhanced. Therefore, safety can be improved.

Then, by suppressing the backflow of the therapeutic substance that occurs along the outer surface of the catheter 10, the backflow of the therapeutic substance from the catheter 10 is mainly performed in the CED method of the therapeutic substance into the living tissue, particularly the brain parenchyma. Because it can prevent leakage to the brain surface, cerebral sulcus, excision space, etc., the distribution efficiency of therapeutic substances is reduced, side effects due to unnecessary administration of medication, brain tissue damage, infection The possibility of the occurrence of complications such as these can be reduced, and it can contribute to the realization of a more accurate, safe and effective CED method.

Furthermore, since the medical device 1 according to the present embodiment has a structure capable of increasing the outer diameter of the catheter 10 only at the time of administration / delivery of the therapeutic substance, the insertion or removal of the catheter 10 from or into the brain parenchyma. Sometimes brain tissue damage can be minimized. This is very effective in minimizing functional complications in brain tissue that performs different functions depending on the site.

Moreover, since the expansion part 30 is formed in the outer periphery of the tubular part 20 all over, the effect which suppresses the back flow of the therapeutic substance mentioned above, the effect which prevents the movement of the catheter 10, and omission, the expansion of the expansion part 30 It is possible to further enhance the effect of dispersing the load on the living tissue.

Moreover, since the expansion part 30 is formed with a length that is 100% of the insertion length L of the tubular part 20 into the living tissue, the effect of preventing the catheter 10 from moving or coming out can be further enhanced.

Further, since the catheter 10 is used for convection increased delivery of the therapeutic substance to the tumor, it becomes possible to effectively deliver the therapeutic substance to the tumor.

Moreover, since the catheter 10 is used for the convective increase delivery of the therapeutic substance to the brain, it becomes possible to effectively deliver the therapeutic substance to the brain.
Second Embodiment

The medical device 50 according to the second embodiment is different from the medical device 1 according to the first embodiment in that the catheter 60 has two expansion portions. In addition, the part which has the same function as 1st Embodiment attaches | subjects the same symbol, and abbreviate | omits description.

As shown in FIG. 5, the catheter 60 includes a tubular portion 70 in which a delivery lumen 71 for delivering a therapeutic substance and an expansion lumen 72 into which an expansion fluid flows are formed, and an outer peripheral surface of the tubular portion 70. The tubular portion 70 and the tubular first extending portion 81 and the second extending portion 82 arranged so as to constitute a double tube, and the hub 40 fixed to the proximal end of the tubular portion 70 are provided. .

The second expansion portion 82 is a region on the distal end side of the tubular portion 70, and a distal end portion and a proximal end portion are joined to the outer peripheral surface of the tubular portion 70. The first extension portion 81 has a distal end portion joined to the tubular portion 70 on the proximal end side of the second extension portion 82, and a proximal end portion joined to the distal end of the hub 40. A space between the first expansion portion 81 and the tubular portion 70 communicates with the expansion lumen 72 through a first through hole 73 formed in the tubular portion 70, and between the second expansion portion 82 and the tubular portion 70. This space communicates with the expansion lumen 72 through a second through hole 74 formed in the tubular portion 70. When the expansion fluid flows into the expansion lumen 72, the first expansion portion 81 and the second expansion portion 82 are in close contact with the tubular portion 70 as shown in FIG. Expand radially outward. The second expansion portion 82 expands larger than the first expansion portion 81 outward in the radial direction of the tubular portion 70 during expansion. The second expansion portion 82 preferably has an outer diameter of 100.1 to 1000% as compared with the outer diameter of the expanded first expansion portion 81 when expanded. The second expansion portion 82 is preferably provided at a position of 0 to 10 mm from the most distal end of the catheter 60 (tubular body 70), but is not limited thereto. As described above, in the second embodiment, the expansion portion 80 is divided into the two first expansion portions 81 and the second expansion portion 82, and extends over the substantially entire region from the distal end portion to the proximal end portion of the tubular portion 70. Be placed. In addition, although the 2nd expansion part 82 is formed separately from the 1st expansion part 81, you may form integrally. Moreover, although the 1st expansion part 81 and the 2nd expansion part 82 expand with the fluid from the same expansion lumen 72, a different expansion lumen may be provided and each may be expandable independently.

In the medical instrument 50 according to the second embodiment, the catheter 60 has a second expansion portion 82 that can be expanded radially outward of the tubular portion 70 when fluid flows into the distal end side of the first expansion portion 81. Therefore, the first expansion portion 81 and the second expansion portion 82 have the effect of suppressing the backflow of the therapeutic substance, the effect of preventing the movement and removal of the catheter 60, and the expansion portion (the first expansion portion 81 and the second expansion portion). The effect of distributing the load on the living tissue due to the expansion of the expansion unit 82) can be arbitrarily adjusted.

Further, since the second expansion portion 82 expands larger than the first expansion portion 81 radially outward of the tubular portion 70 during expansion, the backflow of the therapeutic substance can be effectively suppressed by the second expansion portion 82. . At this time, since the second expansion portion 82 is positioned on the distal end side with respect to the first expansion portion 81, the backflow of the therapeutic substance is effectively performed by the second expansion portion 82 upstream of the first expansion portion 81. Can be suppressed. Further, since the amount of expansion is reduced in the first expansion unit 81 on the downstream side of the second expansion unit 82, it is possible to reduce the load on the living tissue while exhibiting a predetermined backflow suppressing effect.

In the present embodiment, the delivery lumen 71 and the expansion lumen 72 are formed inside one tubular portion 70, but the delivery lumen 71 and the expansion lumen 72 may be formed in different tubular bodies.
<Third Embodiment>

The medical instrument 90 according to the third embodiment is different from the medical instrument 1 according to the first embodiment in that the catheter 100 has two expansion portions. In addition, the part which has the same function as 1st Embodiment attaches | subjects the same symbol, and abbreviate | omits description.

As shown in FIG. 6, the catheter 100 forms a tubular portion 110 in which a delivery lumen 111 for delivering a therapeutic substance is formed, and a tubular portion 110 and a double tube on the outer peripheral surface of the tubular portion 110. A cylindrical first extension part 121 arranged as described above, and a cylindrical second extension part 122 arranged on the outer peripheral surface of the first extension part 121 so as to form a double pipe with the first extension part 121 And a hub 40 fixed to the proximal end of the tubular portion 110.

The first extended portion 121 has a distal end portion joined to the distal end of the tubular portion 110 and a proximal end portion joined to the distal end of the hub 40. An expansion lumen 112 is formed between the first expansion portion 121 and the tubular portion 110. The second extended portion 122 is a region on the distal end side of the first expanded portion 121, and a distal end portion and a proximal end portion are joined to the outer peripheral surface of the first expanded portion 121. The expansion lumen 112 between the first expansion portion 121 and the tubular portion 110 communicates with the expansion opening 42 of the hub 40, and the space between the second expansion portion 122 and the first expansion portion 121 is the first. It communicates with the expansion lumen 112 through a through hole 113 formed in the expansion portion 121.

When the expansion fluid flows into the expansion lumen 112, the first expansion portion 121 and the second expansion portion 122 are in close contact with the tubular portion 110 as shown in FIG. From the state where the portion 122 is in close contact with the first expansion portion 121, the first expansion portion 121 and the second expansion portion 122 expand radially outward as shown in FIG. 6B. Since the second expansion portion 122 is disposed on the outer peripheral surface of the first expansion portion 121, the second expansion portion 122 expands larger than the first expansion portion 121 radially outward of the tubular portion 110 during expansion. The second expansion portion 122 preferably has an outer diameter of 100.1 to 1000% as compared with the outer diameter of the expanded first expansion portion 121 at the time of expansion, but is not limited thereto.

The second expansion portion 122 is preferably provided at a position of 0 to 10 mm from the most distal end of the catheter 100 (tubular body 110), but is not limited thereto. As described above, in the third embodiment, the expansion portion 120 is divided into the two first expansion portions 121 and the second expansion portion 122, and extends over the entire area from the distal end portion of the tubular portion 110 to the proximal end portion. Be placed. In addition, although the 2nd expansion part 122 is formed separately from the 1st expansion part 121, you may form integrally. Moreover, although the 1st expansion part 121 and the 2nd expansion part 122 expand with the fluid from the same expansion lumen 112, a different expansion lumen may be provided and each may be expandable independently. In addition, a plurality of second expansion portions 122 may be provided on the outer periphery of the first expansion portion 121.

In the medical instrument 90 according to the third embodiment, the catheter 100 is provided on the outer periphery of the first expansion portion 121 and can be expanded radially outward of the tubular portion 110 when fluid is introduced. 122, the first dilating portion 121 and the second dilating portion 122 have the effect of suppressing the backflow of the therapeutic substance, the effect of preventing the catheter 100 from moving and coming off, and the dilating portion (the first dilating portion 121 and the first dilating portion 121). 2) The effect of distributing the load on the living tissue due to the expansion of the expansion unit 122) can be arbitrarily adjusted.

Moreover, since the 2nd expansion part 122 expands larger than the 1st expansion part 121 to the radial direction outward of the tubular part 110 at the time of expansion, the backflow of a therapeutic substance can be effectively suppressed by the 2nd expansion part 122. . Since the 2nd expansion part 122 is located in the outer periphery of the front-end | tip part of the 1st expansion part 121, the backflow of a therapeutic substance can be effectively suppressed by the 1st expansion part 121. FIG. Moreover, since the expansion amount is reduced in the first expansion unit 121, it is possible to reduce the load on the living tissue while exhibiting a predetermined backflow suppressing effect.

Note that the present invention is not limited to the above-described embodiment, and various modifications can be made by those skilled in the art within the technical idea of the present invention. For example, as shown in FIGS. 7 and 8, the first expansion portion 131 provided between the second expansion portion 132 and the tubular portion 20 can be partially provided without providing the entire circumference. Naturally, the second extension part 132 provided on the outer periphery of the first extension part 131 may be provided partially rather than on the entire periphery.

Further, as shown in FIG. 9, the second expansion portion 142 provided on the outer peripheral surface of the first expansion portion 141 may be provided on the proximal side with respect to the distal end portion of the catheter.

Moreover, as shown in FIG. 10, the 2nd expansion part 152 provided in the outer peripheral surface of the 1st expansion part 151 may be a disk shape (disk shape). Further, the extended portion may be formed so as to have an elliptical shape instead of a circular shape when viewed from the central axis direction.

Further, as shown in FIG. 11, the tubular portion 170 of the catheter 160 may have a tapered portion 171 whose outer diameter gradually decreases toward the distal end side between the distal end portion 172 and the proximal end portion 173. . The distal end 172 of the tubular portion 170 has a smaller outer diameter than the proximal end 173. By providing the tapered portion 171 in addition to the expansion portion 180, the backflow of the therapeutic substance along the outer surface of the catheter 160 is more effectively suppressed, and the living tissue is expanded while the living tissue is expanded by the tapered portion 171. By making it penetrate in, damage to a living tissue can be suppressed as much as possible.

The outer diameter of the tapered portion 171 preferably decreases gradually at an angle of 2 ° to 60 ° with respect to the central axis of the catheter 160, more preferably decreases gradually at an angle of 2 ° to 45 °. Formed. If the angle of the taper portion 171 is too large, damage to the brain parenchyma will increase, and if the angle of the taper portion 171 is too small, the effect of backflow in the taper portion 171 will decrease. Instead of the tapered portion 171, a step portion whose outer diameter decreases in a direction perpendicular to the central axis of the catheter may be provided.

Further, as shown in FIG. 12, as a core material for imparting rigidity to the catheter 10 when the catheter 10 is inserted, a stylet 190 (core that can be inserted into the catheter 10 so as to penetrate the delivery lumen 21 of the catheter 10 is provided. Material part) may be provided. The stylet 190 is pulled out after the catheter 10 is placed in the living tissue. By providing the stylet 190, even the flexible catheter 10 that is difficult to be inserted into a living tissue can be inserted into a target site with high accuracy. The catheter 10 may be provided with another lumen different from the delivery lumen 21 and the expansion lumen 22 and the stylet 190 may be inserted therethrough. A plurality of lumens different from the delivery lumen 21 and the expansion lumen 22 may be provided.

Further, after the guide wire is first delivered into the living tissue, the catheter 10 can be inserted along the guide wire.

Further, in order to guide the catheter 10 to the brain parenchyma, a separate tube body that can be inserted through the catheter 10 may be used.

As shown in FIG. 13, the distal end portion and the proximal end portion of the expansion portion 210 provided on the catheter 200 are joined to the outer peripheral surface of the tubular portion 220, and an expansion lumen 222 is formed between the expansion portion 210 and the tubular portion 220. It may be formed. The expansion lumen 222 communicates with the delivery lumen 221 through a through hole 223 formed in the tubular portion 220. In this way, by connecting the expansion lumen 222 to the delivery lumen 221, the positive pressure is obtained by utilizing the characteristic that a continuous positive pressure acts on the therapeutic substance when the therapeutic substance is delivered by the delivery lumen 221. Thus, the expansion part 210 can be expanded, and the backflow of the therapeutic substance along the outer surface of the catheter 200 can be suppressed. As the positive pressure increases and the backflow is more likely to occur, the expansion portion 210 expands with a higher positive pressure, and the backflow suppression effect increases. In addition, the extended part 210 can set a position and the length of a central-axis direction suitably like the extended part in the above-mentioned various embodiment.

Also, the configurations provided in the various embodiments described above can be implemented in appropriate combination.

In addition, the medical devices according to the various embodiments described above deliver a therapeutic substance to a brain tumor, but the delivery site is not limited to the tumor, and for example, the liver, pancreas, kidney, gallbladder, breast, It may be a living tissue other than the brain, such as the uterus. Medical devices can be inserted into non-luminal regions that are not biological lumens (blood vessels, vessels, ureters, etc.) and deliver various substances into the non-luminal regions of biological tissue.

1,50,90 medical instruments,
10, 60, 100, 160, 200 catheter,
20, 70, 110, 170, 220 tubular section,
21, 71, 111, 221 delivery lumen,
22, 72, 112, 222 Extended lumen,
30, 80, 120, 180, 210 extension,
81, 121, 131, 141, 151 first extension,
82, 122, 132, 142, 152 second extension,
190 Stylet (core material part),
L Length that can be inserted.

Claims

A medical device for delivering a substance into a living tissue through a non-luminal region of the living tissue,
A tubular portion extending in a long length, and formed on the outer periphery of the tubular portion so as to extend from the distal end portion to the proximal end side of the tubular portion with a length that is 30% or more of the length of the tubular portion that can be inserted into a living tissue. And an expansion portion expandable radially outward of the tubular portion, and a delivery lumen for delivering the substance, and a fluid for expanding the expansion portion into the expansion portion. A medical device having a catheter in which an expansion lumen is formed.
The medical device according to claim 1, wherein the expansion portion is formed around the outer periphery of the tubular portion.
The medical device according to claim 1 or 2, wherein the expansion portion is formed with a length that is 100% of the insertion length of the tubular portion into the living tissue.
The extension is
A first extension provided on the outer periphery of the tubular part;
2. A second expansion portion that is provided at a distal end side relative to the first expansion portion or on an outer periphery of the first expansion portion, and is expandable radially outward of the tubular portion by flowing a fluid. The medical instrument according to any one of 1 to 3.
The medical instrument according to claim 4, wherein the second expansion portion expands larger than the first expansion portion outward in the radial direction of the tubular portion during expansion.
The medical device according to any one of claims 1 to 5, further comprising a core member inserted into the delivery lumen or another lumen different from the delivery lumen.
The medical device according to any one of claims 1 to 6, which is used for increased convection delivery of a substance to a tumor.
The medical device according to any one of claims 1 to 7, which is used for increased convection delivery of a substance to the brain.