JP2013226219A - Stent, warming device for thermotherapy and thermotherapy apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stent for locally warming a specific part of a predetermined part while warming the predetermined part by using electromagnetic waves even if having a comparatively simple configuration; a warming device for thermotherapy; and a thermotherapy apparatus.SOLUTION: A long stent to be disposed in a body cavity includes: a propagating section for propagating freely electromagnetic waves from one end side of the stent to the other end side thereof; and a leaking section for leaking a part of the electromagnetic waves propagated by the propagating section to the outside of the stent between the one end of the stent and the other end thereof so that a specific part of a predetermined part can be locally warmed while warming a whole predetermined part of the body cavity when the electromagnetic waves are propagated by the propagating section.

Description

  The present invention relates to a stent, a heating device for thermotherapy, and a thermotherapy device, and more particularly to a stent used for heating an affected area with electromagnetic waves, a heating device for thermotherapy, and a thermotherapy device.

  So far, hyperthermia is known in which treatment is performed by controlling a tumor present in the body at a constant temperature.

  At this time, as an instrument used for temperature control, a microwave antenna inserted into a stent can be cited (for example, see Non-Patent Document 1).

  As the microwave antenna, a coaxial cable is mainly used (for example, see Patent Document 1). As a specific configuration of the coaxial cable, a coaxial cable having a concentric cross-section and provided with a central conductor, a dielectric, an outer conductor, and a coating in order from the center can be cited. Hereinafter, the microwave antenna is also simply referred to as “antenna”.

  Then, the slit is formed by removing the outer conductor and the coating in a part of the coaxial cable to expose the dielectric. Patent Document 1 describes that the affected area is heated by radiating a microwave from the slit.

  On the other hand, when a malignant tumor develops in a luminal viscera such as the digestive tract and falls into a stenotic state or an obstructed state, a stent made of metal material or the like is inserted to secure patency, and the lumen is inserted. Conventionally, a treatment method for enlarging the diameter and maintaining the inner diameter of the lumen has been performed. Hereinafter, this treatment method is referred to as “stent method”.

  Various patent literatures are known as techniques employing this stent method. Among them, for example, Patent Documents 2 and 3 are known as techniques that employ the stent method for thermotherapy.

  In Patent Document 2, a hollow electrode body is used as a metal stent placed endoscopically in a living body lumen, and a high frequency is applied between the metal stent and an electrode placed outside the body to surround the metal stent. A technique for preventing excessive heating by supplying a cooling liquid into the hollow electrode body when thermotreating the affected area is described.

  Further, in Patent Document 3, a shape memory alloy ring provided on the stent is used to thermally treat the affected area around the stent by exciting a stent using a metal material or the like with a transdermal energy transmission unit outside the body. In addition, a technique is described in which a peristaltic motion is performed in a stent and contents are transferred to an affected area.

Japanese Patent Laid-Open No. 9-164215 JP-A-9-140807 JP 2007-135965 A

Kazuyuki Saito et al, IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES. VOL. 54, NO. 8, AUGUST 2006 (p. 3443-3449)

  Certainly, by using a metal stent, even when a malignant tumor occurs and falls into a stenosis state or an occlusion state, the lumen can be expanded and the inner diameter of the lumen can be maintained. However, when a thermal treatment using an antenna is performed after adopting a stent method using a metal stent as shown in FIG. 6A, the stent is shielded against electromagnetic waves generated from the antenna because the stent is made of metal. Will play the role of. Therefore, as shown in FIG. 6B (SAR distribution showing the intensity distribution of the electromagnetic wave of Comparative Example 1 described later), the electromagnetic wave cannot reach the affected area, and it is difficult to appropriately heat the affected area. Become.

  Even if the central conductor is exposed at one end of the antenna as shown in FIG. 7A and the exposed portion protrudes from one end of the stent, FIG. 7B (the intensity of electromagnetic waves in Comparative Example 2 described later) SAR distribution indicating the distribution) and FIG. 8B (in the comparative example 2 when the SAR distribution is captured with an infrared camera), this time, only the vicinity of the exposed portion and the other end side of the stent are It will be heated locally. As a result, it is not only possible to appropriately heat the affected area, but it is impossible to deny the possibility that the affected area will be excessively heated and chemically denatured.

  When resin is used as the material for the stent, electromagnetic waves do not propagate through the stent in the first place, so only the portion where the electromagnetic waves are generated in the antenna and the inside and outside of the stent around the portion are locally heated. Eventually, it becomes difficult to properly heat the affected area.

  In the case of Patent Document 2, a high-frequency oscillator is provided outside the body, and a stent and an extracorporeal electrode are connected thereto to perform thermal treatment (for example, [0014]). Furthermore, in the case of Patent Document 3, the periphery of the stent is heated by providing an excitation means outside the body (for example, [0011]). When the configurations of Patent Documents 2 and 3 are adopted, thermal treatment must be performed in cooperation with a device provided outside the body. In this case, the thermotherapy device itself must be large, and the thermotherapy operation itself becomes complicated. In addition, the cost of the thermal treatment itself is increased, and there is a considerable burden on the operator and the patient.

  In addition to those problems, in the first place, the antenna provided with the slit as in Non-Patent Document 1 and Patent Document 1 can appropriately heat only the range of about 1 cm in width in the longitudinal direction from the position of the slit. On the other hand, the length of the stent is usually 4 to 5 cm, and even if the affected area can be heated through the stent, it can be heated only in a part of the stent. Usually, when a malignant tumor develops and grows, the malignant tumor has a size that can cover the entire stent. Nevertheless, if it is possible to heat only a part of the stent, it will be necessary to apply heat treatment several times, which will put a considerable burden on the surgeon and patient, It can also increase the risk of leaving an untreated area.

  In addition, when the presence of the malignant tumor is sparse in the affected area in the body cavity, it is preferable to locally heat the portion where the malignant tumor is dense. However, in the prior art, no stent has been considered from the viewpoint of the density of malignant tumors. As a result, the current situation is that the demand for improving the accuracy of warming treatment, which is increasing rapidly, is not fully met.

  An object of the present invention is to locally heat a specific portion of a predetermined portion while heating a predetermined portion in a body cavity with an electromagnetic wave while having a relatively simple configuration. It is to provide a stent, a heating device for heat treatment, and a heat treatment device.

  The present inventors examined a stent for solving the above problems. As described above, as shown in FIGS. 7B and 8B, the present inventors use a metal stent, expose the central conductor at one end of the antenna, and expose the exposed portion to the stent. The distribution state of electromagnetic waves and the distribution state of temperature when protruding from one end side of the glass were investigated.

  The present inventors have obtained new findings from FIG. 7B and FIG. 8B. That is, it was found that not only the vicinity of the exposed portion of the central conductor of the antenna is heated but also the vicinity of the other end of the stent. This is because although electromagnetic waves are emitted somewhat on one end side of the stent near the exposed portion of the central conductor of the antenna, the electromagnetic waves propagate without leaking from this one end to the other end. The inventors speculated that most of the electromagnetic waves were emitted at the other end.

  Therefore, the present inventors, based on the above knowledge, when the electromagnetic wave propagates in the stent, before the majority of the electromagnetic wave that was not leaked is released at the other end (that is, from one end of the stent). I came up with a method of intentionally leaking electromagnetic waves to the outside of the stent until the other end. With this method, even in the thermal treatment using the antenna while adopting the stent method, it is possible to adjust so as to heat the entire affected area in a range corresponding to the width of the stent without excessively heating both ends of the stent. I got the knowledge. Not only that, the knowledge that the specific part can be locally heated by making the part which leaks electromagnetic waves correspond to the specific part (for example, part where a malignant tumor is dense) in an affected part was acquired. And it was found that external electrodes and excitation means are not always necessary and can be realized.

Aspects of the present invention based on the above findings are as follows.
The first aspect of the present invention is:
A long stent for placement in a body cavity,
A propagation part for allowing electromagnetic waves to propagate freely from one end side of the stent to the other end side;
When propagating electromagnetic waves by the propagation part, one end of the stent is heated so that a specific part of the predetermined part is locally heated while the entire predetermined part in the body cavity is heated. Between the side and the other end side, a leakage portion that allows a part of the electromagnetic wave propagated by the propagation portion to leak to the outside of the stent,
It is a stent characterized by having.
A second aspect of the present invention is the aspect described in the first aspect,
The propagation part contains a metal, and the leakage part contains a resin.
A third aspect of the present invention is the aspect described in the first or second aspect,
The propagation part includes a braided metal wire, and the leaking part includes a plastic wire stent.
The fourth aspect of the present invention is:
A long stent having a hollow structure for placement in a body cavity;
An antenna that is inserted into the stent and generates electromagnetic waves;
Have
The stent is
A propagation part for propagating electromagnetic waves generated from the antenna from one end side to the other end side of the stent;
While the whole predetermined part in the body cavity outside the stent is heated, a specific part of the predetermined part is heated locally from one end side to the other end side so as to be locally heated. In between, a leakage part that leaks a part of the electromagnetic wave propagated by the propagation part to the outside of the stent,
It is the heating apparatus for thermotherapy characterized by having.
A fifth aspect of the present invention is the aspect described in the fourth aspect,
The propagation part contains a metal, and the leakage part contains a resin.
A sixth aspect of the present invention is the aspect described in the fourth or fifth aspect,
The propagation part includes a braided metal wire, and the leaking part includes a plastic wire stent.
A seventh aspect of the present invention is the aspect according to any one of the fourth to sixth aspects,
The antenna is long, and a central conductor is exposed at one end of the antenna to such an extent that electromagnetic waves can be generated, and the exposed portion protrudes from one end of the stent.
According to an eighth aspect of the present invention, there is provided a thermotherapy device incorporating the warming device for thermotherapy according to any one of the fourth to seventh embodiments.

  According to the present invention, while heating a predetermined part in a body cavity with an electromagnetic wave, the specific part of the predetermined part is locally heated while having a relatively simple configuration. A stent, a heating device for heat treatment, and a heat treatment device can be provided.

It is the schematic which shows a mode that the thermotherapy apparatus in this embodiment is used. It is the schematic which shows the outline | summary of a structure of the thermotherapy apparatus in this embodiment. It is a figure which shows the heating apparatus for the thermal treatment in this embodiment, and is an enlarged view of the antenna which comprises it. (A) is a figure which shows the stent in Example 1, (b) is a figure which shows the measurement result of the SAR distribution around a stent at the time of using the thermotherapy apparatus of Example 1, ( c) The SAR distribution around the stent is captured by an infrared camera. (A) is a figure which shows the stent in Example 2, (b) is a figure which shows the measurement result of the SAR distribution around a stent at the time of using the thermotherapy apparatus of Example 2, ( c) The SAR distribution around the stent is captured by an infrared camera. (A) is a figure which shows the heating apparatus for the thermal treatment in the comparative example 1, (b) shows the measurement result of the SAR distribution around the stent when the thermal treatment apparatus of the comparative example 1 is used. FIG. (A) is a figure which shows the heating apparatus for the thermal treatment in the comparative example 2, (b) shows the measurement result of the SAR distribution around the stent when the thermal treatment apparatus of the comparative example 2 is used. FIG. (A) is a figure which shows the stent in the comparative example 2, (b) is the figure which caught the SAR distribution around the stent with the infrared camera at the time of using the thermotherapy apparatus of the comparative example 2. FIG. It is a figure showing an outline of composition of an endoscope in this embodiment. It is the schematic which shows the outline | summary of the modification of the stent in this embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
In the present embodiment, description will be given in the following order.
1. 1. Outline of configuration of thermotherapy device Heating device for thermotherapy 1) Stent 2) Antenna 3. 3. Description of stent, heating device for thermotherapy, and usage of thermotherapy device 4. Effects of the embodiment Modified example

<1. Overview of thermotherapy device configuration>
FIG. 2 is a schematic diagram showing a configuration example of the thermal treatment apparatus according to the embodiment of the present invention.
The thermotherapy device illustrated in FIG. 2 includes a heating device for thermotherapy having a combination of the stent 1 and the antenna 2 (hereinafter also simply referred to as “heating device”), and an internal insertion channel. A long endoscope 3 in which at least the antenna 2 is detachable, a control unit 4 for controlling the degree of heating of the affected part by the heating device and the operation of the endoscope 3, the antenna 2, the endoscope 3 and A power supply unit 5 that supplies power to the control unit 4 is provided. In FIG. 2, the antenna 2 and the endoscope 3 and the power supply unit 5 are connected by separate lines. Further, the power supply unit 5 and the control unit 4 are also connected by separate lines in order to control the antenna 2 and the endoscope 3. Hereinafter, the heating apparatus according to the present embodiment will be described.

<2. Heating device for thermotherapy>
FIG. 3 is a schematic diagram illustrating a configuration example of the heating device according to the embodiment of the present invention.
First, the heating device according to the present embodiment has a combination of the stent 1 and the antenna 2. The stent 1 is a long one having a hollow structure that is disposed in a body cavity to expand the inside of the body cavity. The antenna 2 is a long one that is inserted into the stent 1 and generates electromagnetic waves (more specifically, microwaves) for heating the affected area. Hereinafter, the stent 1 and the antenna 2 will be described in detail.

  For convenience of explanation, in the long antenna 2, the direction on the side connected to the power supply unit 5 is referred to as the base end side, and the opposite side and the side inserted into the human body is referred to as the end side. That is, the portion where the central conductor of the antenna 2 is exposed in FIG. 3 is the “terminal side of the antenna 2”. The naming method is the same for the stent 1 and the endoscope 3 described below.

1) Stent The stent 1 according to the present embodiment propagates electromagnetic waves by a propagation unit 11 that allows electromagnetic waves to propagate from one end side (terminal side) of the stent 1 to the other end side (base end side), and the propagation unit 11. While the whole predetermined part in the body cavity is heated at the time, so that a specific part of the predetermined part is locally heated, from one end side of the stent 1 to the other end side, A leakage portion 12 that allows a part of the electromagnetic wave propagated by the propagation portion 11 to leak to the outside of the stent 1 is provided.

  “Propagation of electromagnetic waves” in the propagation part 11 means that electromagnetic waves leak only to the extent that electromagnetic waves leak at the distal and proximal ends of the stent 1 (the situation shown in FIG. 7B). In other words, it means that the electromagnetic wave can propagate in the stent 1. Where the electromagnetic wave emission is shielded by the propagation part 11, the leakage part 12 is designed to cancel this shielding state. Therefore, the propagation part 11 can be said to be a shielding part in other words. Accordingly, the expression “propagating electromagnetic waves” can be said to be “shielding electromagnetic waves”. Further, the expression “free propagation of electromagnetic waves” can also be said to be “free to shield electromagnetic waves”.

Conventionally, when the antenna 2 is used while adopting the stent method, the electromagnetic wave for heating the affected area is shielded by the metal stent. Further, in the case of resin, since electromagnetic waves do not propagate through the stent 1 in the first place, only the periphery of the portion where the electromagnetic waves are generated in the antenna 2 is locally heated.
However, while propagating the electromagnetic wave in the stent 1 by the propagation part 11, the leakage part 12 disperses the intensity of the electromagnetic wave concentrated on the distal side and the proximal side of the stent 1 to some extent. By doing so, as shown in FIG. 4B (an SAR distribution of the electromagnetic wave intensity of Example 1 described later), the electromagnetic wave intensity can be appropriately dispersed and concentrated in a specific portion. As a result, as shown in FIG. 4C (a diagram in which the SAR distribution is captured with an infrared camera in Example 1 described later), the affected area around the stent 1 can be heated. In addition, this heating can also locally heat a specific part according to the arrangement of the leakage part 12. Moreover, this heating can be carried out without using an extracorporeal electrode or excitation means, although the structure is relatively simple.

In the present specification, at least a part (preferably the entire part) of the “affected part” corresponds to “the entire predetermined part in the body cavity”. That is, “the entire predetermined part in the body cavity” refers to at least a part of the part where the target (for example, malignant tumor) to be treated by the warming treatment apparatus in the present embodiment exists or its periphery. The “specific part” refers to a part (for example, a part where the malignant tumor is denser than the surroundings) where the person who uses the warming treatment apparatus in the present embodiment desires to warm the affected part at a particularly high temperature. .
That is, the arrangement of the leaking portion 12 can be selected according to the position of the leaking portion according to the range of the portion where the heating is desired locally. Therefore, even if the affected part has occurred at various positions, it is possible to locally warm the surroundings of the stent 1 in an adaptable manner by adjusting the position of the leakage part 12 each time. As a specific position of the leakage part 12, although it is an example, it is preferable to arrange 5 mm away from the distal end and the distal end of the stent 1. By carrying out like this, it becomes possible to perform appropriate heating (especially local heating). In this case, the length of the appropriate heating portion in the longitudinal direction of the stent 1 is about 2 cm.

  Note that “electromagnetic wave leakage freely” in the leakage portion 12 is a situation in which the electromagnetic wave can be released to the outside of the stent when the electromagnetic wave propagates from the distal end side to the proximal end side of the stent 1. Refers to that. In other words, an electric field is induced in the leakage portion 12 when electromagnetic waves propagate from the distal end side to the proximal end side of the stent 1, and as shown in FIG. It refers to the situation where electromagnetic waves can be emitted outside the stent.

  By the way, it is preferable that the propagation part 11 contains a conductor and the leakage part 12 contains a nonconductor. As a specific example, it is preferable that the propagation part 11 contains a metal and the leakage part 12 contains a resin as an insulator. By doing so, it is possible to reliably propagate the electromagnetic wave in the propagation unit 11 while reliably leaking the electromagnetic wave in the leakage unit 12. Moreover, the stent 1 was arrange | positioned in a body cavity by comprising the propagation part 11 and the leakage part 12 as a substance, without making the space | gap (air) play the role in both the propagation part 11 and the leakage part 12. In this case, the risk of breakage can be reduced, and the life and stability of the stent 1 in the body cavity can be improved.

  More specifically, the propagation part 11 is made of a metal wire (conductive material) woven, and the leaking part 12 is woven of a plastic wire (a material having lower conductivity than the propagation part 11). Consists of things. A thing including this propagation part 11 and the leakage part 12 is mentioned as an example of the stent 1 of this embodiment. More specifically, a hollow wire formed by knitting a metal wire (for example, a plastic wire stent) prepared by knitting a plastic wire is prepared. For example, a plurality of metal stents are fitted. A plurality of metal stents are arranged at predetermined positions on the outer periphery of the plastic wire stent so as to cover at least a part of the plastic wire stent. In this case, the metal stents are arranged so as to be separated from each other. In other words, it is preferable to dispose a plurality of hollow metal stents apart from each other so that electromagnetic waves leak to appropriately heat the affected area. At this time, it is preferable that at least the terminal side of the stent 1 is the propagation portion 11. By doing so, it is possible to suppress at least only the vicinity of the portion where the central conductor 21 is exposed in the antenna 2 from being excessively heated. It should be noted that the propagation part 11 (or the leakage part 12 in some cases) may be appropriately disposed on the distal side of the stent 1 so as not to be heated excessively.

In this embodiment, first, a long and hollow plastic wire stent is formed by knitting a plastic wire. Separately, the metal wire is knitted to form a short and hollow metal stent. At that time, the inner diameter of the metal stent is set to be equal to or larger than the outer diameter of the plastic wire stent. A plurality of the metal stents are fitted into the plastic wire stent so as to be separated from each other. This metal stent constitutes the propagation part 11, and a plastic wire stent part (a spaced part where no metal stent is present) becomes a leaking part 12. In addition, the metal stent which comprises the propagation part 11 is densely knitted to such an extent that electromagnetic waves can propagate freely. Regarding the propagation part 11, since the method of braiding a metal wire is simple, there is an advantage that the propagation part 11 can be easily manufactured. The same applies to the leaking portion 12, and since the method of braiding the plastic wire is simple, the leaking portion 12 can be easily manufactured. In addition, with the above configuration, it is possible to maintain appropriate elasticity, and there is an advantage that when the stent 1 is placed in a body cavity, the stent can be held well in the affected area.
After the plastic wire is knitted to form the plastic wire stent, the method of fitting the metal stent knitted with the metal wire into the outer periphery of the plastic wire stent is simple, so that the stent 1 can be easily manufactured. As described above, the affected part can be heated using the antenna 2 while adopting the stent method.

  Further, the number of the separated portions where the metal stent does not exist (hereinafter also referred to as “plastic wire stent exposed portion”) may be single or plural as long as the entire predetermined portion can be heated. If the number is singular, it is possible to heat a portion corresponding to only one exposed portion of the plastic wire stent at a higher temperature. If there are a plurality of electromagnetic waves, it is possible to leak electromagnetic waves at a plurality of locations, and local heating can be performed at a milder temperature than a single one. For example, as shown in FIG. 10, if the leakage portions 12 (for example, the first plastic wire stent exposed portion 12 a and the second plastic wire stent exposed portion 12 b) are formed in the upper and lower portions of the stent 1, While the portion corresponding to the portion can be subjected to relatively high-temperature heating treatment, the entire predetermined portion can be appropriately heated. In addition, what is necessary is just to adjust suitably the width | variety of the plastic wire stent exposed part in a elongate direction so that a specific part can be heated locally, heating the whole predetermined part. For example, in the case of FIG. 10, the lengths of the long portions of the first plastic wire stent exposed portion 12a and the second plastic wire stent exposed portion 12b are different depending on the position and range of the portion to be heated at a high temperature. You may let them. Of course, both widths may be equal. Similarly, the length of the elongated portion of the propagation part 11 (for example, the first metal stent to the third metal stent (11a to 11c)) may be determined as appropriate, and the lengths may be different or equal. You may do it.

2) Antenna The antenna 2 in the present embodiment may be a microwave antenna 2 that generates an electromagnetic wave in a part of the antenna 2. For example, the antenna 2 described in Patent Document 1 or Non-Patent Document 1 (that is, from the end to the base end) Alternatively, the antenna 2 (the antenna 2 described in FIG. 6 of Comparative Example 1 described later) in which the slits 25 are formed may be used. When the outline of the antenna 2 is shown again, a coaxial cable is used as the antenna 2 in the present embodiment. As shown in FIG. 3, a central conductor 21, a dielectric 22, an outer conductor 23, What provided the coating | cover 24 is used.

  In the present embodiment, the long antenna 2 in which the central conductor 21 is exposed at one end of the antenna 2 and the exposed portion protrudes from one end side of the stent 1 is used. The central conductor 21 may be completely exposed, or the central conductor 21 may be covered to the extent that electromagnetic waves can be generated.

  The antenna 2 is inserted into the body orally together with the endoscope 3, and is allowed to pass through the sphincter muscle (the hole of the papilla 63) between the duodenum 61 and the biliary tract 62.

  In addition, although the stent 1 may be preliminarily disposed in the body cavity, a heating device already combined with the antenna 2 may be used. In the present embodiment, a case will be described in which the stent 1 is disposed in advance in the body cavity and the antenna 2 is inserted through the stent 1.

<3. Description of stent, heating device for thermotherapy, and method of using thermotherapy device>
Hereinafter, regarding a stent, a heating device for thermotherapy, and a method of using the thermotherapy device, FIG. 1 which is a schematic diagram showing a state of using the thermotherapy device in the present embodiment, and an outline of the endoscope in the present embodiment This will be described with reference to FIG. 9 which is a perspective view. In the following items, as described above, the case where the above-described stent 1 is previously placed in the biliary tract 62 and the antenna 2 is inserted into the stent 1 will be described.

  The endoscope 3 according to this embodiment is configured such that at least the antenna 2 can be inserted. Further, as shown in FIG. 9, on the distal end side of the endoscope 3, photographing for confirming the insertion state of the guide wire and / or the antenna 2 (hereinafter referred to as the antenna 2) into the nipple 63. The raising part 33 which changes the advancing direction of the part 31, the illumination part 32 which provides the light required for imaging | photography by the imaging | photography part 31, and the antenna 2 to a desired direction is provided.

  The photographing unit 31 only needs to have an accuracy enough to project the state of the nipple 63, and the illumination unit 32 only needs to provide a light that allows this photographing. The photographing unit 31 and the illumination unit 32 are supplied with power from the power supply unit 5 described above, and the operation is controlled by the control unit 4.

  Further, the raising portion 33 is provided inside the endoscope 3, and, like the photographing unit 31 and the illumination unit 32, power is supplied from the power supply unit 5 and the operation is controlled by the control unit 4.

  Specifically, after the endoscope 3 having a heating device for thermotherapy is inserted orally and then reaches the duodenum 61 before the biliary tract 62 and the nipple 63, the raised portion 33 is in a folded state. And stored in the endoscope 3.

Then, when approaching the vicinity of the nipple 63, the raising portion 33 is operated by the control unit 4 to stand up as shown in FIG. Then, adjustment is made so that the antenna 2 and the like are directed toward the papilla 63 on the side wall of the duodenum 61.
Then, while the illumination unit 32 illuminates the vicinity of the nipple 63, the imaging unit 31 captures the state of inserting the antenna 2 and the like.
The operator inserts the antenna 2 or the like through the hole of the nipple 63 while photographing in this way.

  Thereafter, the antenna 2 is inserted into the stent 1 already placed in the biliary tract 62. Then, the antenna 2 is arranged so that the central conductor 21 exposed to the extent that electromagnetic waves can be generated at the end of the antenna 2 protrudes from the end side of the stent 1.

  In this way, the antenna 2 is left in the biliary tract 62 (in the stent 1), the affected part 64 is heated by the electromagnetic wave emitted from the antenna 2, and the thermal treatment is performed.

  The feature of this embodiment is that the above-described stent 1 is used for this thermal treatment. First, in the present embodiment, the central conductor 21 is exposed at the end of the antenna 2, and the exposed portion protrudes from the end side of the stent 1. In this state, when power is supplied from the power supply unit 5 to the antenna 2, electromagnetic waves are emitted around the exposed portion of the center conductor 21. However, even if electromagnetic waves are emitted at the end of the stent 1, the electromagnetic waves normally propagate through the stent 1 toward the proximal end. However, the stent 1 of this embodiment includes not only the propagation part 11 but also the leakage part 12. Therefore, when the electromagnetic wave is emitted centering on the exposed portion of the central conductor 21 and the electromagnetic wave propagates from the distal side of the stent 1 toward the proximal side, as shown in FIG. While the electromagnetic wave propagates from the base to the base end, the electromagnetic wave leaks from the leaking part 12 as needed. The degree of leakage is adjusted so that a specific portion of the predetermined portion is locally heated while the entire predetermined portion in the body cavity is heated. Finally, when the electromagnetic wave propagates to the proximal end of the stent 1 and is emitted from the proximal end, the electromagnetic wave has an appropriate strength.

The degree of leakage is adjusted such that when propagating electromagnetic waves by the propagation unit 11, the specific part is locally heated while heating the entire predetermined part in the body cavity in the longitudinal direction. On the other hand, in the radial direction, adjustment is performed so that only the affected part is heated. The heating range in the radial direction depends on where the affected part is in the patient's body. In the case of the biliary tract 62 as mentioned in this embodiment, it is only necessary to heat the luminal surface of the biliary tract 62 to a depth of about 1 cm. By carrying out like this, excessive warming can be suppressed and the possibility of heating to an adjacent organ can also be suppressed. Further, it is preferable that the affected area is in a range of 40 ° C. or higher and 45 ° C. or lower by heating. If it is 40 ° C. or higher, the effect of hyperthermia can be expected, and if it is 45 ° C. or lower, it is not necessary to chemically denature the organ.
The specific method of adjusting the leakage degree of electromagnetic waves is as described above, and is adjusted as needed depending on the number and arrangement of the exposed portions of the plastic wire stent. By doing so, electromagnetic waves are appropriately leaked to the outside of the stent 1 from the proximal end to the distal end of the stent 1, and a specific portion is locally heated while heating the entire predetermined portion. Can be heated.

  “Warming the entire predetermined portion” means that the normal tissue of the affected area is not chemically denatured, and no residual heating is generated in the affected area, or even if it occurs, it is locally caused by the leakage portion 12 of the stent 1. It refers to a situation where the entire periphery of the stent 1 is heated to such an extent that there is no remaining heating due to heating.

<4. Advantages of the embodiment>
According to this embodiment, the following effects can be obtained.
First, by using the stent 1, even when a malignant tumor grows and falls into a stenosis state or an occlusion state, the lumen can be expanded and the inner diameter of the lumen can be maintained. When the affected area is heated by the antenna 2 after adopting the stent method, the affected area in the range corresponding to the length of the stent 1 in the longitudinal direction can be appropriately heated. In addition, when the malignant tumor exists in the affected area in the body cavity at the time of the warming, it is possible to locally heat the portion where the malignant tumor is dense.

  As a result, even if the malignant tumor is large enough to cover the entire stent 1, not only the portion that emits electromagnetic waves in the antenna 2 but also the periphery of the stent 1 is added to a wider area than before. Since it can be warmed, it is not necessary to apply heat treatment several times. As a result, it is possible to suppress the possibility of leaving an untreated part in the affected area without imposing a burden on the operator and the patient.

  Furthermore, excessive warming can be suppressed, and the possibility that the affected area may be chemically denatured can be suppressed. As a result, it is possible to improve the accuracy of the warming treatment that is currently increasing rapidly.

  In addition, by using the stent 1 of the present embodiment, a heating device using the antenna 2 can be configured. That is, it is not necessary to perform the thermal treatment in cooperation with a device provided outside the body, such as an extracorporeal electrode or excitation means, and the thermal treatment apparatus itself can be made compact. As a result, the thermal treatment work itself can be simplified, the cost of the thermal treatment itself can be reduced, and the burden on the operator and the patient can be reduced.

  As described above, according to the present embodiment, an electrode outside the body and excitation means are not required, and the predetermined portion in the body cavity is heated by electromagnetic waves while having a relatively simple configuration. A stent for locally heating a specific portion of the portion, a heating device for thermal therapy, and a thermal therapy device can be provided.

<5. Modification>
In the present embodiment, an example of a configuration in which one long plastic wire stent is prepared and a plurality of short metal stents are fitted apart from each other is described. Other than that, a plurality of plastic wire stents are prepared, a metal stent having a larger diameter is fitted on the outer periphery of both ends of the plastic wire stent, and another plastic wire stent is installed in the hollow portion at the other end of the metal stent. For example, a connecting structure of a plastic wire stent and a metal stent may be adopted.
On the other hand, the metal stent is reduced in diameter, a larger diameter plastic wire stent is fitted around the outer periphery of the metal stent, and another metal stent is inserted into the hollow portion at the other end of the plastic wire stent. The connection structure of, may be adopted.
Also, a medium diameter plastic wire stent is fitted into one end of a small diameter metal stent, and a large diameter metal stent is fitted into the other end of the medium diameter plastic wire stent. You may employ | adopt a connection structure suitably in the predetermined part of the stent 1. FIG.

  A method of forming the propagation part 11 and the leakage part 12 by inserting a plurality of plastic rings into one metal stent is also conceivable. A method of using a tubular resin (so-called plastic stent) instead of the braided plastic wire stent is also conceivable. That is, the leakage portion may be formed of a plastic stent, and a plurality of portions where the plastic stent is exposed may exist. Similar to the plastic wire stent, one plastic stent may be prepared and a metal stent may be fitted therein, or a plurality of plastic stents may be prepared and connected by the metal stent.

  After all, the propagation part 11 in the present embodiment may be other than metal as long as it can propagate electromagnetic waves, or the propagation part 11 may be formed by a method other than braiding of a metal wire. The leaking portion 12 may be other than a resin as long as it can leak electromagnetic waves to the outside of the stent 1, and a member other than the stent may be used. After all, it functions as a surgical stent, and while heating a predetermined portion, the intensity of electromagnetic waves around the stent 1 so as to locally heat a specific portion of the predetermined portion. The shape and material of the propagation part 11 and the leaking part 12 are not particularly limited.

  Moreover, although it depends on the usage environment of the heating device, the leakage portion 12 may be a gap. In other words, this is a case where the propagation portion 11 and the leakage portion 12 are configured by adjusting the magnitude relationship of the dielectric constant of the surrounding atmosphere, the propagation portion 11 and the leakage portion 12 (more precisely, the ease of inducing an electric field). However, the present invention can be applied.

  Moreover, you may provide structures other than the propagation part 11 and the leakage part 12 in the stent 1 as needed.

  In the thermotherapy apparatus according to the present embodiment, an example in which an extracorporeal electrode or excitation means is not used has been described. However, an extracorporeal electrode may be used for reasons such as adding a separate heating source or assisting in heating. Alternatively, excitation means may be used. However, as described above, it is preferable not to use external electrodes or excitation means in terms of reducing the burden on the operator or patient.

  Next, an Example is shown and this invention is demonstrated concretely. Of course, the present invention is not limited to the following examples.

Example 1
The stent 1 of the present example was configured as follows.
First, as the propagation part 11, two metal stents (inner diameter: 5.0 mm, length: 25 mm) configured in a hollow shape (tubular shape) by braiding a metal wire (Ni wire) were prepared. These metal stents are a first metal stent, a second metal stent (11a to 11b), and a leakage portion 12, which is a plastic wire stent (inner diameter: 4.0 mm) formed hollow by knitting a plastic wire. , 15 mm in length) was used. Then, two hollow metal stents (11a to 11b) were fitted into the plastic wire stent so as to cover both ends of the plastic wire stent.

  At that time, as shown in FIGS. 3 and 4A, the two metal stents (11a to 11b) were separated from each other. Then, a portion where the plastic wire stent was exposed (that is, a portion where there is no metal stent and a so-called plastic wire stent exposed portion) (12a) was provided. While the total length of the stent 1 was 60 mm, the width of the exposed portion of the plastic wire stent in the longitudinal direction was 10 mm, and the exposed portion was disposed at the center of the stent 1. A photograph of the stent 1 used in Example 1 is shown in FIG.

Next, the antenna 2 of the present example was configured as follows.
The antenna 2 of the present embodiment is a flexible coaxial antenna 2 (also referred to as a coaxial probe), and is configured to be able to locally heat. As shown in FIG. 3, a dielectric 22, an outer conductor 23, and a coating 24 are provided in the circumferential direction when viewed from the center conductor 21, and the center conductor 21 is exposed at the end of the antenna 2. The length of the antenna 2 was 2.5 m, and the outer diameter of the antenna 2 was 2.4 mm. Moreover, the length of the exposed part in the center conductor 21 was 3.0 mm.

  An antenna 2 was inserted through the cylindrical stent 1. At that time, the exposed portion of the central conductor 21 is arranged to protrude from the terminal side of the stent 1. Thus, a heating apparatus for thermotherapy in this example was produced.

(Example 2)
In Example 2, the length of each metal stent is 37 mm, the total length of the stent 1 is 80 mm, the width of the exposed portion of the plastic wire stent in the longitudinal direction is also 10 mm, and the exposed portion is the center of the stent 1. Arranged. The rest was the same as in Example 1. In addition, the photograph of the stent 1 used in Example 2 is shown in FIG.

(Comparative Example 1)
In Comparative Example 1, only one metal stent 11 ′ was used as the stent. Then, as shown in FIG. 6A, a slit 25 is provided between the terminal end and the base end of the antenna 2, and the antenna 2 that emits electromagnetic waves from the slit 25 is used. And it was set as the arrangement | positioning in which the slit 25 exists in the inside of metal stent 11 '. The rest was the same as in Example 1.

(Comparative Example 2)
In Comparative Example 2, as shown in FIGS. 7A and 8A, only the metal stent 11 ′ was used as the stent. The rest was the same as in Example 1.

(Evaluation test)
In the evaluation test, a power supply unit was provided for the heating devices of Example 1 and Comparative Examples 1 and 2, and a thermotherapy device was produced. Then, the heating device (the stent 1 or the metal stent 11 ′ and the antenna 2) in the thermotherapy device was inserted into the phantom.

  Note that the phantom is a substance for artificially measuring the energy of electromagnetic waves absorbed by the human body. In the evaluation test of this example, the phantom described in the example of the patent document (Japanese Unexamined Patent Application Publication No. 2009-036684) disclosed by the present inventors was used. The SAR distribution was measured with the heating device inserted in the phantom as described above. In addition, the observation surface in that case made the observation surface the surface containing the tangent direction when the stent 1 is seen in cross section.

  The power supply from the power supply unit to the antenna 2 was set to an input power of 50 W, a frequency of 2.45 GHz, and a power supply time of 60 seconds. Thus, the SAR distribution after power supply was obtained. Note that SAR (Specific Absorption Rate) is the amount of energy absorbed by a unit mass of tissue per unit time, and how much energy the human body has received from a device that emits electromagnetic waves within a certain period of time. It is shown. And this SAR distribution was measured with respect to Example 1 and Comparative Examples 1-2.

(Evaluation test results)
FIG. 4B shows the result of SAR distribution for Example 1, and FIG. 4C shows the result of capturing the SAR distribution with an infrared camera. FIG. 5B shows the SAR distribution result for Example 2, and FIG. 5C shows the result of capturing the SAR distribution with an infrared camera.
On the other hand, FIG. 6B shows the result of SAR distribution for Comparative Example 1, FIG. 7B shows the result of SAR distribution for Comparative Example 2, and FIG. 8B shows the result of capturing the SAR distribution with an infrared camera. Show.

  Looking at Example 1 (FIG. 4 (b)), if the entire stent 1 is a metal stent, electromagnetic waves should propagate from the distal end to the proximal end of the stent 1, due to the presence of the exposed portion (12a) of the plastic wire stent. It can be seen that electromagnetic waves leak between the first metal stent and the second metal stent (11a to 11b). And it turns out that the leak has arisen in the plastic wire stent exposed part (12a). And it turns out that the electromagnetic wave of moderate intensity | strength has been emitted in the proximal end of the stent 1. FIG. As a result, as shown in FIG. 4C, it is understood that a specific portion of the predetermined portion can be locally heated while heating the predetermined portion.

  Similarly, when Example 2 (FIG. 5B) is viewed, the same tendency is shown. As a result, as shown in FIG. 5 (c), it is understood that a specific portion of the predetermined portion can be locally heated while heating the predetermined portion.

  On the other hand, in Comparative Example 1 (FIG. 6B), it can be seen that the electromagnetic wave is shielded by the metal stent 11 ′ because the slit 25 of the antenna 2 is housed in the metal stent 11 ′. . Therefore, the electromagnetic wave is emitted only at the base end side of the metal stent 11 ′. As a result, only the base end side of the metal stent 11 ′ can be heated, and the outside of the metal stent 11 ′ is heated. I can't understand.

  Moreover, when the comparative example 2 (FIG. 7 (a) (b), FIG. 8 (a) (b)) is seen, since the exposed part in the center conductor 21 protrudes from metal stent 11 ', metal stent 11' Electromagnetic waves are emitted on the terminal side, and this part is heated. However, electromagnetic waves are shielded by the metal stent 11 ′ from the end to the base end of the metal stent 11 ′. For this reason, extremely high intensity electromagnetic waves are emitted on the proximal end side of the metal stent 11 ′. As a result, only the distal side and the proximal side of the metal stent 11 'can be heated. In addition, the metal stent 11 'is heated excessively on the distal side and the proximal side. 4 (b) and 5 (b), some electromagnetic waves are leaking from the distal end to the proximal end of the metal stent 11 'except for the leaking portion 12. The cause of this is as follows. Are under intensive investigation.

DESCRIPTION OF SYMBOLS 1 ... Stent 11 ... Propagation part 11a ... 1st metal stent 11b ... 2nd metal stent 11c ... 3rd metal stent 11 '... Metal stent 12 ... Leakage Part 12a: First plastic wire stent exposed portion 12b: Second plastic wire stent exposed portion 2 ... Antenna 21 ... Center conductor 22 ... Dielectric 23 ... Outer conductor 24 .... Cover 25 ... Slit 3 ... Endoscope 31 ... Imaging part 32 ... Illumination part 33 ... Raising part 4 ... Control part 5 ... Power supply part 61 ... Duodenum 62 ・ ・ ・ Biliary tract 63 ・ ・ ・ Furter papilla 64 ・ ・ ・ affected part

Claims (8)

A long stent for placement in a body cavity,
A propagation part for allowing electromagnetic waves to propagate freely from one end side of the stent to the other end side;
When propagating electromagnetic waves by the propagation part, one end of the stent is heated so that a specific part of the predetermined part is locally heated while the entire predetermined part in the body cavity is heated. Between the side and the other end side, a leakage portion that allows a part of the electromagnetic wave propagated by the propagation portion to leak to the outside of the stent,
A stent characterized by comprising:   The stent according to claim 1, wherein the propagation part contains a metal, and the leakage part contains a resin.   The stent according to claim 1 or 2, wherein the propagation part includes a braided metal wire, and the leakage part includes a plastic wire stent. A long stent having a hollow structure for placement in a body cavity;
An antenna that is inserted into the stent and generates electromagnetic waves;
Have
The stent is
A propagation part for propagating electromagnetic waves generated from the antenna from one end side to the other end side of the stent;
While the whole predetermined part in the body cavity outside the stent is heated, a specific part of the predetermined part is heated locally from one end side to the other end side so as to be locally heated. In between, a leakage part that leaks a part of the electromagnetic wave propagated by the propagation part to the outside of the stent,
A heating device for thermal therapy, characterized by comprising:   The warming device for thermotherapy according to claim 4, wherein the propagation part contains a metal, and the leakage part contains a resin.   The warming device for thermotherapy according to claim 4 or 5, wherein the propagation part includes a braided metal wire, and the leaking part includes a plastic wire stent.   5. The antenna according to claim 4, wherein the antenna is long, and the central conductor is exposed at one end of the antenna to such an extent that electromagnetic waves can be generated, and the exposed portion protrudes from one end of the stent. The heating apparatus for thermotherapy as described in any one of 6 thru | or 6. A thermotherapy device incorporating the heating device for thermotherapy according to any one of claims 4 to 7.