Light irradiation probe

Abstract

Provided is a light irradiation probe with a novel structure, the light irradiation probe being capable of surgically treating a lateral treatment target by bringing an irradiation part, which is provided at the distal end of an optical fiber, into contact with the treatment target.　A light irradiation probe 10 has a heat-resistant optical fiber 16 whose distal end section serves as an irradiation part 30 for irradiating light, and performs surgical treatment, by means of irradiation light, on a treatment target with which the irradiation part 30 of the optical fiber 16 is brought into contact. The distal end side of the optical fiber 16 extends while being inclined in the lateral direction with respect to the base end side thereof. The irradiation part 30 is provided with a heat generation coating layer 32 made of a light absorption substance that generates heat by absorbing the irradiation light from the irradiation part 30.

Description

Light irradiation probe

[0001] The present invention relates to a light irradiation probe for surgically treating a treatment target such as a lesion in the body with light irradiated from an irradiation part of an optical fiber, and particularly relates to a light irradiation probe for surgically treating by bringing an irradiation part that generates heat by irradiation light into contact with the treatment target.

[0002] Conventionally, a light irradiation probe for surgically treating a treatment target such as a lesion in the body with light (irradiation light) irradiated from an irradiation part at the tip of an optical fiber has been known. In addition to the non-contact type in which light is irradiated from a position separated from the treatment target to perform surgical treatment, there is also a contact type in which, as disclosed in Japanese Patent Application Laid-Open No. 2004-141374 (Patent Document 1), the irradiation part is brought into contact with the treatment target while irradiating light to perform surgical treatment. In Patent Document 1, by coarsening the tip part of the optical fiber and providing a laser light absorption layer on the tip part of the optical fiber, the tip part generates heat and it is possible to efficiently surgically treat the treatment target. Conventionally, as a contact type light irradiation probe, for example, by attaching a carbide to the irradiation part of the optical fiber, the carbide absorbs the irradiation light and generates heat, thereby increasing the treatment efficiency of the treatment target is known.

[0003] Japanese Patent Application Laid-Open No. 2004-141374

[0004] By the way, in addition to the dental treatment exemplified in Patent Document 1, the light irradiation probe may also be used for treating stenosis in a biological lumen, such as represented by benign prostatic hyperplasia. In the treatment of such cases, the light irradiation probe is inserted into the working channel of an endoscope or the lumen of an access catheter used in combination with an endoscope, and the treatment target such as a lesion is surgically treated with the light irradiation probe under the endoscope.

[0005] However, in the treatment using an endoscope such as benign prostatic hyperplasia, the treatment target such as hypertrophic fibrous tissue may be located laterally with respect to the insertion and extraction direction of the light irradiation probe with respect to the working channel of the endoscope. In this case, with a light irradiation probe using an optical fiber as in Patent Document 1, it may be difficult to bring the irradiation part into contact with the treatment target.

[0006] Furthermore, since the optical fiber is inserted into the work channel of an endoscope or the lumen of an access catheter used in conjunction with an endoscope, if the tip of the optical fiber is roughened as in Patent Document 1, the ease of insertion into the work channel or lumen may decrease, making it more likely to get stuck, or there is a risk of damaging the inner surface of the working channel of the endoscope or the lumen of the access catheter.

[0007] Furthermore, as has been known for some time, when carbon deposits are attached to the tip of an optical fiber, the process of attaching the carbon deposits before use is time-consuming, and there is a risk that the working channel of the endoscope or the lumen of the access catheter may become contaminated with carbon deposits.

[0008] The problem to be solved by the present invention is to provide a novel optical irradiation probe that enables surgical treatment of a target to be treated by bringing the irradiation part provided at the tip of an optical fiber into contact with the target to be treated laterally.

[0009] The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is illustrative and can be combined with others as appropriate. Furthermore, the multiple components described in each embodiment can be recognized and adopted as independently as possible, and can be combined with any component described in another embodiment as appropriate. Thus, the present invention is not limited to the embodiments described below, and various other embodiments can be realized.

[0010] The first embodiment is a light irradiation probe having a heat-resistant optical fiber whose tip is an irradiation part that emits light, and in which a target to be treated is brought into contact with the irradiation part of the optical fiber and surgically treated with the irradiated light, wherein the tip side of the optical fiber extends at a lateral inclination relative to the base side, and the irradiation part is provided with a heat-generating coating layer made of a light-absorbing material that absorbs the irradiated light from the irradiation part and generates heat.

[0011] According to the light irradiation probe structured in accordance with this embodiment, since the tip of the optical fiber extends at a lateral inclination, the irradiation part provided at the tip of the optical fiber can be easily brought into contact with the object to be treated, which is located laterally with respect to the direction of insertion and removal of the optical fiber. By irradiating the object to be treated with light while the irradiation part is in contact with the object to be treated, the heating coating layer is heated, allowing the object to be surgically treated by inserting and removing the optical fiber.

[0012] Because the irradiation area is pre-equipped with a heat-generating coating layer made of a light-absorbing material, the cutting performance can be improved by pressing the irradiation area, which has been heated by light irradiation, against the treatment target, without the need for the conventional method of attaching carbides to the irradiation area.

[0013] The second embodiment is the light irradiation probe described in the first embodiment, wherein the heat-generating coating layer is provided only partially on the irradiation portion, without covering the entire portion.

[0014] According to the light irradiation probe with a structure conforming to this embodiment, since the heat-generating coating layer is partially provided on the irradiation part, the irradiation of light on the irradiation part can be visually confirmed, for example, during endoscopic procedures.

[0015] A third embodiment is the light irradiation probe described in the second embodiment, wherein the heat-generating coating layer is provided on the side of the irradiation section that is being treated.

[0016] According to the light irradiation probe with a structure conforming to this embodiment, a heat-generating coating layer that generates heat upon light irradiation is partially provided on the treatment target side of the irradiation unit. This allows for efficient surgical treatment of the treatment target with the heat-generating portion of the irradiation unit, while also allowing confirmation of light irradiation in the portion without the heat-generating coating layer.

[0017] The fourth embodiment is a light irradiation probe described in any one of the first to third embodiments, wherein the light-absorbing material forming the heat-generating coating layer is mainly composed of either carbon or a precious metal.

[0018] According to the light irradiation probe structured in accordance with this embodiment, by employing a heat-generating coating layer mainly composed of carbon or precious metals, the heat-generating coating layer can be effectively heated by light irradiation. Furthermore, the heat-generating coating layer, which consists of a light-absorbing material mainly composed of carbon or precious metals, is minimally invasive to the human body and stable against heating by light irradiation, making it suitable for use inside the body. In addition, by employing a light-absorbing material mainly composed of carbon, the heat-generating coating layer can be formed inexpensively.

[0019] The fifth embodiment is a light irradiation probe described in any one of the first to fourth embodiments, wherein the irradiation portion is spherical.

[0020] According to the light irradiation probe structured in this embodiment, the irradiation portion constituting the tip of the optical fiber is spherical, so, for example, when inserting the optical fiber into the lumen of an access catheter, the tip of the optical fiber is less likely to get caught on the inner surface of the catheter, and the catheter is less likely to be damaged. Furthermore, by making the irradiation portion spherical, the contact area of ​​the irradiation portion with the treatment target can also be increased.

[0021] The sixth aspect is an optical irradiation probe described in any one of the first to fifth aspects, wherein the optical fiber has an optical transmission loss in water of less than 20% of the incident light amount.

[0022] According to the optical irradiation probe structured in this embodiment, light can be efficiently transmitted to the irradiation part at the tip of the optical fiber, enabling excellent surgical treatment performance by pressing the irradiation part against the surface.

[0023] The seventh embodiment is an optical irradiation probe described in any one of the first to sixth embodiments, wherein the optical fiber is fitted with a reinforcing member that maintains a relative inclination angle between its tip and proximal ends, and the irradiation portion of the optical fiber is exposed on the tip side of the reinforcing member.

[0024] According to the optical irradiation probe structured in this embodiment, the inclination angle of the tip of the optical fiber is stably maintained because a reinforcing member is attached to the optical fiber. Furthermore, since damage to the optical fiber due to reaction force when, for example, the irradiation part is pressed against the treatment target is prevented, the irradiation part can be pressed against the treatment target with the force necessary for the surgical procedure, thereby improving the surgical treatment performance.

[0025] The eighth aspect is a light irradiation probe having a heat-resistant optical fiber whose tip is an irradiation part that emits light, and in which a target to be treated is brought into contact with the irradiation part of the optical fiber and surgical treatment is performed with the irradiated light, wherein a reinforcing member is attached to the outer circumference of the optical fiber, the irradiation part is exposed on the tip side of the reinforcing member, and the tip portion of the optical fiber is held in a bent shape in which the tip side is inclined laterally with respect to the base side by being fitted from one side into a recess formed in the reinforcing member.

[0026] According to the light irradiation probe structured in accordance with this embodiment, since the tip of the optical fiber extends at a lateral inclination, the irradiation part provided at the tip of the optical fiber can be easily brought into contact with the object to be treated, which is located laterally with respect to the direction of insertion and removal of the optical fiber. By irradiating the object to be treated with light while the irradiation part is in contact with the object to be treated, the object can be surgically treated by inserting and removing the optical fiber.

[0027] The attachment of a reinforcing member to the optical fiber ensures that the inclination angle of the tip of the optical fiber is stably maintained. Furthermore, damage to the optical fiber due to reaction force when, for example, the irradiation part is pressed against the treatment target is prevented, allowing the irradiation part to be pressed against the treatment target with the force necessary for the surgical procedure, thereby improving the performance of the surgical procedure. Since the irradiation part of the optical fiber is exposed on the tip side of the reinforcing member, it is possible to avoid the reinforcing member obstructing the application of the irradiation part to the treatment target.

[0028] Furthermore, the reinforcing member is attached to the optical fiber by fitting the optical fiber into a groove from one side. Therefore, the lateral inclination angle of the tip portion of the optical fiber can be maintained by the reinforcing member, which can be easily attached to the optical fiber. In addition, compared to the case where the reinforcing member is provided around the entire circumference of the optical fiber, the outer diameter of the tip portion of the optical irradiation probe can be partially reduced.

[0029] The ninth embodiment is an optical irradiation probe as described in the eighth embodiment, wherein, in the mounting portion of the reinforcing member, the outer surface of the optical fiber is fitted into the groove over a range exceeding half a circumference.

[0030] According to the optical irradiation probe structured in accordance with this embodiment, the optical fiber is less likely to slip out of the groove, and the reinforcing member can be prevented from falling off the optical fiber.

[0031] The tenth embodiment is a light irradiation probe having a heat-resistant optical fiber whose tip is an irradiation part that emits light, and in which a target to be treated is brought into contact with the irradiation part of the optical fiber and surgically treated with the irradiated light, wherein the tip side of the optical fiber extends at a lateral inclination relative to the base side, and a reinforcing member is attached to the optical fiber to maintain the relative inclination angle between the tip side and the base side, and the irradiation part is exposed on the tip side of the reinforcing member, and the reinforcing member is made of an opaque material.

[0032] According to the light irradiation probe structured in accordance with this embodiment, since the tip of the optical fiber extends at a lateral inclination, the irradiation part provided at the tip of the optical fiber can be easily brought into contact with the treatment target located laterally with respect to the direction of insertion and removal of the optical fiber. By irradiating the treatment target with light while the irradiation part is in contact with the treatment target, the treatment target can be surgically treated by inserting and removing the optical fiber.

[0033] The attachment of a reinforcing member to the optical fiber ensures that the inclination angle of the tip of the optical fiber is stably maintained. Furthermore, damage to the optical fiber due to reaction force when, for example, the irradiation part is pressed against the treatment target is prevented, allowing the irradiation part to be pressed against the treatment target with the force necessary for the surgical procedure, thereby improving surgical performance. Since the irradiation part of the optical fiber is exposed on the tip side of the reinforcing member, it is possible to avoid the reinforcing member obstructing the application of the irradiation part to the treatment target.

[0034] Because the reinforcing member is made of an opaque material, light transmitted through the optical fiber is less likely to leak out at the attachment point of the reinforcing member. This reduces light transmission loss and improves the surgical performance of the irradiation area. In particular, by attaching the reinforcing member made of an opaque material to the bent portion of the optical fiber, where light leakage is likely to occur, light transmission loss is efficiently reduced.

[0035] The eleventh embodiment is an optical irradiation probe described in any one of the eighth to tenth embodiments, wherein a protective jacket for protecting the optical fiber is attached to the base end portion of the optical fiber in an external state, and the reinforcing member is connected to the tip side of the protective jacket.

[0036] According to the optical irradiation probe structured in this embodiment, damage to the optical fiber is more easily prevented because the optical fiber is covered with a protective jacket. Furthermore, since the reinforcing member is connected to the protective jacket that is externally fitted to the optical fiber, the reinforcing member is prevented from falling off the optical fiber.

[0037] The twelfth embodiment is an optical irradiation probe described in any one of the eighth to eleventh embodiments, wherein the surface of the reinforcing member on the optical fiber side is provided with a heat dissipation layer having a higher thermal conductivity than the reinforcing member.

[0038] According to the light irradiation probe structured in accordance with this embodiment, even if light from an optical fiber is irradiated onto the reinforcing member, the temperature rise of the reinforcing member due to light irradiation is mitigated by the improved heat dissipation performance of the reinforcing member due to the provision of a heat dissipation layer. Therefore, even if the reinforcing member comes into contact with body tissue, damage to the body tissue due to contact with the reinforcing member is avoided.

[0039] According to the present invention, in an optical irradiation probe, it becomes possible to perform surgical procedures on a target to be treated by bringing the irradiation part provided at the tip of the optical fiber into contact with the target to be treated to the side.

[0040] Right side view showing a light irradiation probe as the first embodiment of the present invention. Longitudinal cross-sectional view of the light irradiation probe shown in Figure 1. Enlarged view of the tip portion of the optical fiber constituting the light irradiation probe shown in Figure 1. Right side view showing an enlarged view of the reinforcing member constituting the light irradiation probe shown in Figure 1. Enlarged front view of the reinforcing member shown in Figure 4. Enlarged view of part VI in Figure 2. More detailed cross-sectional view.

[0041] Embodiments of the present invention will be described below with reference to the drawings.

[0042] Figures 1 and 2 show a light irradiation probe 10 as a first embodiment of the present invention. The light irradiation probe 10 has a structure in which a connector 14 is provided on the base end side of an optical fiber core 12. In the following description, as a general rule, the vertical direction refers to the vertical direction in Figure 1, the front-back direction refers to the left-right direction in Figure 1, and the left-right direction refers to the direction perpendicular to the plane of the paper in Figure 1.

[0043] The optical fiber core 12 has a structure in which the base end of the optical fiber 16 is covered with a resin coating layer 18. The coating layer 18 includes, for example, a buffer 20 as a primary coating layer that covers the outer surface of the optical fiber 16, and a protective jacket 22 as a secondary coating layer that covers the outer surface of the buffer 20. The coating layer 18 is formed such that the buffer 20 is made of an ultraviolet-curing resin or the like, and the protective jacket 22 is made of polyamide or polyethylene or the like. It is desirable that the coating layer 18 be made of an opaque, light-impermeable material in order to reduce the transmission loss of the optical fiber 16.

[0044] The optical fiber 16 is a long optical waveguide formed by bundling a large number of spun linear dielectrics, and is capable of transmitting light in the longitudinal direction between the proximal end and the distal end. The optical fiber 16 has, for example, a structure in which a cladding layer with a low refractive index is provided around a core with a high refractive index, and light is repeatedly totally reflected at the boundary between the core and the cladding layer and propagates in the core in the longitudinal direction. It is desirable that the optical fiber 16 has an optical transmission loss in water of less than 20% of the incident light amount, and more preferably less than 15%. The optical fiber 16 is, for example, a silica-based or multi-component glass fiber or a resin-made plastic fiber, and is preferably a silica-based glass fiber. The optical fiber 16 has heat resistance that allows the temperature rise of the irradiation unit 30 described later, and it is desirable, for example, that it allows heating up to 500 degrees.

[0045] The optical fiber 16 is in the shape of a long rod extending with a substantially constant circular cross-section, and as shown in FIG. 3, it has a bent portion 24 in the middle. The optical fiber 16 extends in a direction relatively inclined with respect to the base end portion 28, which is on the base end side (left side in FIG. 1) of the bent portion 24, at the tip inclined portion 26, which is on the tip side (right side in FIG. 1) of the bent portion 24. In the present embodiment, the base end portion 28 extends in the front-rear direction and is non-inclined in the vertical and horizontal directions. Also, the tip inclined portion 26 is inclined downward as it goes toward the tip side (leftward in FIG. 1). It is desirable that the relative inclination angle α of the tip inclined portion 26 with respect to the base end portion 28 is set within the range of 5 to 30 degrees, and more preferably within the range of 10 to 20 degrees. The tip inclined portion 26 and the base end portion 28 each extend linearly. The bent portion 24 has a curved shape inclined downward toward the tip side.

[0046] At the tip of the optical fiber 16, an irradiation unit 30 is integrally provided. The irradiation unit 30 is a portion irradiated with the light transmitted from the proximal end side of the optical fiber 16, and is substantially spherical in this embodiment. The diameter of the spherical irradiation unit 30 is larger than the diameter of the optical fiber 16 on the proximal end side of the irradiation unit 30 having a substantially cylindrical shape, and the irradiation unit 30 protrudes to the outer periphery. Since a part of the proximal end side of the irradiation unit 30 is joined to the tip inclined portion 26 of the optical fiber 16, it has a spherical segment shape, and the outer peripheral surface has a spherical crown shape with a superior arc cross-sectional shape.

[0047] On the irradiation unit 30, a heat generating coating layer 32 formed of a light absorbing substance is formed. The heat generating coating layer 32 absorbs the light energy irradiated on the irradiation unit 30 and converts it into heat, and is fixed to the surface of the irradiation unit 30. The heat generating coating layer 32 is formed of a light absorbing substance mainly composed of, for example, carbon or a noble metal. Specifically, for example, the heat generating coating layer 32 is a thin film such as diamond-like carbon (DLC), gold, platinum, silver, etc., and is formed by vapor deposition on the irradiation unit 30.

[0048] The heat generating coating layer 32 is partially formed on the irradiation unit 30. The heat generating coating layer 32 is formed, for example, so as to cover the lower part of the irradiation unit 30 and is not formed on the upper part of the irradiation unit 30. The range in which the heat generating coating layer 32 is formed in the irradiation unit 30 is not particularly limited, but is preferably formed over 30% or more of the outer peripheral surface of the irradiation unit 30, and more preferably formed over 40% or more. Since the lower part of the irradiation unit 30 is pressed against the treatment target (body tissue) as will be described later, the heat generating coating layer 32 is provided on the treatment target side.

[0049] A reinforcing member 34 is attached to the optical fiber 16. As can be seen from Figures 4 and 5, the reinforcing member 34 has a roughly rectangular cross-section and extends for a predetermined length in the front-to-back direction. The base end of the reinforcing member 34 extends linearly with a roughly constant cross-sectional shape in the front-to-back direction, while the tip end slopes downward toward the tip. The outer dimensions of the tip end of the reinforcing member 34 are larger in the vertical direction than those of the base end. The vertical dimensions of the tip end of the reinforcing member 34 gradually increase toward the tip and then gradually decrease. Both the upper and lower surfaces of the reinforcing member 34 are composed of smooth curved surfaces without bends or folds. The reinforcing member 34 is made of a rigid material, and may be made of, for example, synthetic resin, but preferably of a metallic material such as stainless steel or titanium alloy. In order to suppress light leakage from the optical fiber 16, it is desirable that the reinforcing member 34 be an opaque material made of an opaque material that does not transmit light.

[0050] A heat dissipation layer 36 is provided on the surface of the reinforcing member 34. The heat dissipation layer 36 is made of a material with a higher thermal conductivity than the reinforcing member 34 and covers the surface of the reinforcing member 34 partially or entirely. The heat dissipation layer 36 is made of, for example, gold, aluminum, or a thermally conductive resin (a resin material made by mixing a metal powder with high thermal conductivity into a resin base material). The heat dissipation layer 36 is provided on the surface of the reinforcing member 34, including the right side which is the mounting side for the optical fiber 16, which will be described later. In this embodiment, the heat dissipation layer 36, which is made of gold plating, is provided over the entire surface of the reinforcing member 34.

[0051] The reinforcing member 34 has a groove 38 that opens to the right. The groove 38 extends continuously in the front-rear direction and opens to both the front and rear ends of the reinforcing member 34. The groove 38 has a substantially semicircular groove cross-sectional shape that corresponds to the outer surface of the optical fiber 16. Preferably, the groove 38 has a concave cross-sectional shape that slightly exceeds half a circumference. The base end of the groove 38 extends linearly in the front-rear direction, and the tip end is partially bent at a position corresponding to the bent portion 24 of the optical fiber 16, and extends inclined with respect to the front-rear direction along the tip inclined portion 26. The inclined portion of the groove 38 is tapered, slightly widening toward the tip, allowing for tolerance of errors in the shape of the optical fiber 16.

[0052] The upper and lower wall portions of the groove 38 in the reinforcing member 34 are thicker on the curved tip side than on the straight base side. The upper wall portion 40 of the groove 38 in the reinforcing member 34 has a starting position for its downward inclination that is closer to the tip than the lower wall portion 42 of the groove 38. The inclined portion of the upper surface of the upper wall portion 40 of the reinforcing member 34 has a smaller radius of curvature than the inclined portion of the lower surface of the lower wall portion 42. The tips of both the upper and lower portions of the reinforcing member 34 are composed of an upper tip cover portion 44 that protrudes from the upper wall portion 40 toward the tip side and a lower tip cover portion 46 that protrudes from the lower wall portion 42 toward the tip side. The tip cover portions 44 and 46 protrude beyond the groove 38 toward the tip side. The tip cover portions 44 and 46 are both tapered in the vertical direction toward the tip, and their upper and lower inner surfaces are concave curved surfaces that widen outwards in the upper and lower directions to avoid interference with the outer surface of the irradiation portion 30 of the optical fiber 16.

[0053] As shown in Figures 1 and 2, the optical fiber 16 is inserted into the groove 38 of the reinforcing member 34, and in this embodiment, it is positioned relative to the other by being fitted together without adhesive. When the optical fiber 16 is inserted into the groove 38 from the right side and the reinforcing member 34 is attached to the tip of the optical fiber 16, the inclination angle of the tip inclined portion 26 with respect to the base end 28 of the optical fiber 16 is maintained, and the optical fiber 16 is held in a predetermined bent shape. Therefore, when performing surgical procedures on body tissue as described later, the irradiation unit 30 can be pressed more firmly against the body tissue, thereby improving and stabilizing the surgical procedure performance. Furthermore, for example, even if a reaction force is applied to the optical fiber 16 when the irradiation unit 30 is pressed against body tissue during surgical procedures on body tissue, the relative tilting between the tip inclined portion 26 and the base end 28 is suppressed, preventing the optical fiber 16 from breaking at the bent portion 24. The optical fiber 16 may also be inserted into the groove 38 with a gap and fixed to the reinforcing member 34 by means of adhesive or other means.

[0054] In this embodiment, the groove 38 has a superior arc shape with a cross-sectional shape slightly exceeding half a circumference, and the outer surface of the optical fiber 16 is fitted into the groove 38 over a range exceeding half a circumference. This makes it difficult for the optical fiber 16 to come out of the groove 38, for example, when the irradiation part 30 of the optical fiber 16 is pressed more strongly against the object to be treated. Furthermore, because the optical fiber 16 is difficult to come out of the groove 38, even if the reinforcing member 34 is attached to the optical fiber 16 without adhesive, the reinforcing member 34 is prevented from falling off the optical fiber 16. Note that the optical fiber 16 does not need to be fitted into the groove 38 over a range exceeding half a circumference over the entire mounting portion of the reinforcing member 34; it may be fitted in a range exceeding half a circumference in a part or multiple places in the longitudinal direction of the mounting portion of the reinforcing member 34. In this case, the groove 38 of the reinforcing member 34 may have a superior arc shape with a cross-sectional shape exceeding half a circumference in a part in the longitudinal direction, and a semi-circular arc shape or inferior arc shape with a cross-sectional shape of less than half a circumference in other parts.

[0055] The irradiation section 30, located at the tip of the optical fiber 16, is positioned away from the tip side of the groove 38 and is exposed from the reinforcing member 34 toward the tip side. The tip cover portions 44 and 46 of the reinforcing member 34, located on both the upper and lower sides of the irradiation section 30, are separated from the irradiation section 30, and a gap is formed between the irradiation section 30 and these tip cover portions 44 and 46.

[0056] The base end of the reinforcing member 34 is connected to the protective jacket 22 that covers the optical fiber 16. That is, as shown in Figure 6, the reinforcing member 34 is attached to the optical fiber 16 at a position away from the tip side of the protective jacket 22, and the reinforcing member 34 and the protective jacket 22 are interconnected by a connecting ring 48. The connecting ring 48 is made of, for example, an alloy of platinum and iridium, and functions as a contrast marker with excellent visibility under X-ray projection. The tip portion of the protective jacket 22 is inserted into the base end of the connecting ring 48, and the base end portion of the reinforcing member 34 is inserted into the tip end of the connecting ring 48, so that the protective jacket 22 and the reinforcing member 34 are bonded to the connecting ring 48. In this way, the protective jacket 22 and the reinforcing member 34 are interconnected by the connecting ring 48.

[0057] A protective tube 50 is interposed between the overlapping surfaces of the reinforcing member 34 and the connecting ring 48, preventing damage to the optical fiber 16 due to direct contact between the rigid connecting ring 48 and the optical fiber 16. The protective tube 50 also protrudes further towards the base end than the reinforcing member 34, covering the exposed portions of the optical fiber 16 and buffer 20 between the reinforcing member 34 and the connecting ring 48. In Figure 6, the protective tube 50 is spaced away from the protective jacket 22 towards the tip end, but it may, for example, be abutted against the end face of the protective jacket 22 or be externally fitted to the tip portion of the protective jacket 22. The buffer 20 covering the surface of the optical fiber 16 is provided to the tip end than the protective jacket 22, but is spaced away from the reinforcing member 34 towards the base end and is not provided on the portion of the optical fiber 16 where the reinforcing member 34 is attached.

[0058] In Figure 6, the gaps between the members on the inner circumference of the connecting ring 48 are filled with adhesive 52. In short, with the protective tube 50 fitted onto and bonded to the optical fiber 16, buffer 20 and reinforcing member 34, the connecting ring 48 is fitted onto and bonded to the optical fiber 16, buffer 20, protective jacket 22, reinforcing member 34 and protective tube 50.

[0059] The proximal end of the optical fiber 16 is connected to the connector 14. The connector 14 is connectable to a light source device (not shown), and connects the optical fiber 16 to the light source device, enabling the supply of light from the light source device to the optical fiber 16. The protective jacket 22 covering the proximal end of the optical fiber 16 is fixed at the proximal end by abutting against a strain relief 54 provided on the tip side of the connector 14.

[0060] The light irradiation probe 10, with the structure described above, is used for surgical procedures such as incision of body tissue to be treated. Specifically, light supplied from a light source device (not shown) to an optical fiber 16 is transmitted to an irradiation unit 30 located at the tip of the optical fiber 16. When this transmitted light is irradiated onto a heat-generating coating layer 32 covering the irradiation unit 30, the heat-generating coating layer 32, which has absorbed the irradiated light, generates heat, resulting in a hot-tip state where the irradiation unit 30 becomes hot. The lower part of the hot-tip irradiation unit 30 is then pressed against body tissue, allowing for efficient surgical treatment of the tissue. Surgical procedures using the light irradiation probe 10 include not only incision of body tissue, but also excision (removal of a portion of body tissue), vaporization of body tissue by heating, and hemostasis and coagulation of the incised or excised portion of body tissue.

[0061] Since the heat-generating coating layer 32 is formed of a light-absorbing material mainly composed of carbon or precious metals, light energy is efficiently absorbed, advantageously improving surgical treatment performance by creating a hot tip on the irradiation section 30. Furthermore, light-absorbing materials mainly composed of carbon or precious metals are less invasive and safe for the human body, and remain stable even when heated to high temperatures by light irradiation, making them easy to use in in-vivo treatments. Compared to light-absorbing materials mainly composed of precious metals, the heat-generating coating layer 32 can be formed at a lower cost using a light-absorbing material mainly composed of carbon.

[0062] Since the heat-generating coating layer 32 is partially formed on the irradiation section 30, light leaks out to the outside in areas where the heat-generating coating layer 32 is not present. As a result, when using the light irradiation probe 10 while visually observing it under an endoscope, it is possible to confirm whether or not light is properly irradiating the irradiation section 30 using the image from the endoscope.

[0063] The optical fiber 16 has an optical transmission loss in water of less than 20% of the incident light amount, and when used in surgical procedures inside the body, the energy loss when transmitting light from the base end to the tip (irradiation section 30) of the optical fiber 16 is sufficiently small. Therefore, the energy absorbed by the heat-generating coating layer 32 is sufficiently large, resulting in high temperatures and thus excellent surgical performance.

[0064] A light irradiation probe 10 with such a structure is used, for example, in surgical procedures such as incision and vaporization of body tissue under endoscopy. Specifically, for example, the light irradiation probe 10 is used in a procedure to incise stenotic structures such as thickened fibrous tissue under endoscopy, with the aim of alleviating chronic functional impairment and pain associated with stenosis of the body's lumen, such as in benign prostatic hyperplasia. Since the light irradiation probe 10 is inserted, for example, into the working channel of an endoscope or the lumen of an access catheter used to guide the endoscope to the affected area, in this case, the maximum vertical dimension with the reinforcing member 34 attached is set to be less than or equal to the inner diameter of the working channel of the endoscope or the lumen of the access catheter. The light irradiation probe 10 has flexibility that allows it to reach the affected area on the proximal end side of the reinforcing member 34, and is designed to be able to flex (bend) along the working channel of an endoscope or the lumen of an access catheter that has been pre-inserted into the body's lumen.

[0065] The reinforcing member 34 has a curved surface on the vertical side where its dimensions increase, and in particular, the surface on the tip side is a tapered curved surface, which prevents it from getting caught on the inner surface of the work channel or lumen of the endoscope or damaging the inner surface of the work channel or lumen when inserted into the work channel or lumen of the access catheter. In addition, since the tip of the optical fiber 16 protruding from the reinforcing member 34 is a spherical irradiation part 30, the optical fiber 16 is also less likely to get caught on the inner surface of the work channel or lumen or damage the inner surface of the work channel or lumen.

[0066] The light irradiation probe 10 inserted into the body can be confirmed by endoscopic imaging, and the position of its tip can also be confirmed by X-ray contrast imaging. In this embodiment, a connecting ring 48 made of a material with excellent contrast-enhancing properties is provided at the joint between the reinforcing member 34 and the optical fiber 16 (protective jacket 22), making it easier to determine the position of the tip of the light irradiation probe 10 by the contrast imaging of the connecting ring 48.

[0067] In this procedure, the thickened tissue to be treated is located laterally (below in Figure 1) to the light irradiation probe 10. However, with the light irradiation probe 10 of this embodiment, it is possible to surgically treat the laterally located thickened tissue by pushing and pulling operations in the longitudinal direction (front-back direction). Specifically, the light irradiation probe 10 of this embodiment has a tip-inclined portion 26 at the tip of the optical fiber 16 that is inclined laterally, and the irradiation portion 30 provided at the tip of the optical fiber 16 protrudes laterally from the base portion 28 of the optical fiber 16. Therefore, by pushing / pulling out the base portion of the optical fiber 16 in the longitudinal direction, the irradiation portion 30 can be moved while in contact with the laterally located thickened tissue. This makes it possible to effectively incise or otherwise treat the thickened tissue located laterally to the light irradiation probe 10.

[0068] The irradiation unit 30 has a heating coating layer 32 covering the lower part of the sloping tip 26 of the optical fiber 16 that protrudes laterally. Since the portion of the irradiation unit 30 covered with the heating coating layer 32 is more likely to come into contact with thickened tissue, the hot-tipped irradiation unit 30 can effectively perform surgical procedures on body tissue.

[0069] The tip portion of the optical fiber 16, which has a bent portion 24, is reinforced by a reinforcing member 34, and the change in the relative inclination angle α between the tip inclined portion 26 and the base portion 28, which are located on both sides of the bent portion 24, is limited by the reinforcing member 34. Therefore, even if, for example, the irradiation portion 30 is pressed strongly against a thickened tissue and a reaction force acts in a direction that reduces the inclination angle α between the tip inclined portion 26 and the base portion 28, damage such as bending or deformation of the optical fiber 16 can be prevented.

[0070] A gap is provided between the reinforcing member 34 and the irradiation unit 30, and the reinforcing member 34 does not directly contact the irradiation unit 30. As a result, heat from the irradiation unit 30 is less likely to be transferred to the reinforcing member 34, allowing the irradiation unit 30 to be efficiently heated with a relatively small amount of energy, and preventing cauterization of body tissue even if the reinforcing member 34 comes into contact with body tissue.

[0071] Furthermore, a heat dissipation layer 36 made of a material with a higher thermal conductivity than the material used to form the reinforcing member 34 is provided on the surface of the reinforcing member 34, including the side facing the optical fiber 16. As a result, even if the reinforcing member 34 absorbs light from the irradiation unit 30 and generates heat, the heat is dissipated to the surroundings from the surface of the reinforcing member 34, which is coated with a heat dissipation coating, thereby suppressing the temperature rise of the reinforcing member 34.

[0072] Although embodiments of the present invention have been described in detail above, the present invention is not limited by its specific description. For example, the irradiation portion provided at the tip of the optical fiber is not necessarily limited to a spherical shape as in the first embodiment. Furthermore, while it is desirable for the irradiation portion to have a larger diameter than other parts of the optical fiber from the viewpoint of surgical treatment performance, it may, for example, have the same diameter as other parts of the optical fiber, or it may have a smaller diameter than other parts.

[0073] In the first embodiment, the optical fiber 16 has a curved or bent shape at the bent portion 24, and the tip inclined portion 26 on the tip side of the bent portion 24 and the base end portion 28 on the base end side are both straight. However, for example, the entire tip portion of the optical fiber may be curved, so that the tip side of the optical fiber extends at a lateral inclination relative to the base end side, and the irradiating portion of the tip of the optical fiber protrudes laterally. Alternatively, the optical fiber may have multiple bent portions 24 at various points along its length, with each portion outside of these bent portions 24 being straight.

[0074] In the first embodiment, the reinforcing member 34 is attached to an optical fiber 16 that has a pre-formed bent portion 24, thereby maintaining the bent shape of the optical fiber 16. However, for example, a straight optical fiber without a bent portion can also be deformed and maintained into a bent shape along the lumen of the reinforcing member by externally inserting a bent cylindrical reinforcing member. It is also possible to insert a straight optical fiber into a reinforcing member 34 that has a groove 38, as in the first embodiment, and deform the optical fiber to conform to the shape of the groove 38. However, when deforming a straight optical fiber into a bent shape by attaching a reinforcing member, the reinforcing member is more likely to fall off due to the shape-restoring force of the optical fiber compared to using an optical fiber 16 that has a pre-formed bent portion 24. Therefore, it is preferable to use a cylindrical reinforcing member that is externally inserted into the optical fiber.

[0075] The reinforcing member is not limited to a rectangular cross-sectional shape as shown in the first embodiment, but can be any of the various cross-sectional shapes, such as circular (including elliptical), semicircular, polygons other than rectangular, or irregular shapes.

[0076] The reinforcing member does not necessarily have to be attached to the optical fiber over its entire length, as in the first embodiment; for example, it may be partially attached to the optical fiber at one or more points along its length. The reinforcing member and the optical fiber may be bonded together, for example, entirely or partially. The reinforcing member and the optical fiber may be mechanically fixed together, for example.

[0077] The light irradiation probe 10 is not necessarily used only for incising thickened tissue, but can be used for incising body tissue in various medical procedures, including dentistry. In addition to incising body tissue, the light irradiation probe 10 may also be used, for example, to stop bleeding by cauterizing internal bleeding sites.

[0078] 10 Light irradiation probe (first embodiment) 12 Optical fiber core 14 Connector 16 Optical fiber 18 Coating layer 20 Buffer 22 Protective jacket 24 Bent portion 26 Tip inclined portion 28 Base portion 30 Irradiation portion 32 Heat-generating coating layer 34 Reinforcement member 36 Heat dissipation layer 38 Groove 40 Upper wall portion 42 Lower wall portion 44 Upper tip cover portion 46 Lower tip cover portion 48 Connecting ring 50 Protective tube 52 Adhesive 54 Strain relief

Claims

1. A light irradiation probe having a heat-resistant optical fiber whose tip is an irradiation part that emits light, wherein a target to be treated is brought into contact with the irradiation part of the optical fiber and surgical treatment is performed by irradiating it with light, wherein the tip side of the optical fiber extends at a lateral inclination relative to the base side, and the irradiation part is provided with a heat-generating coating layer made of a light-absorbing material that absorbs the irradiated light from the irradiation part and generates heat.

2. The light irradiation probe according to claim 1, wherein the heat-generating coating layer is provided partially on the irradiation portion without covering the entire portion.

3. The light irradiation probe according to claim 2, wherein the heat-generating coating layer is provided on the side of the irradiation unit that is being treated.

4. The light irradiation probe according to any one of claims 1 to 3, wherein the light-absorbing material forming the heat-generating coating layer is mainly composed of either carbon or a precious metal.

5. The light irradiation probe according to any one of claims 1 to 3, wherein the irradiation part is spherical.

6. The optical irradiation probe according to any one of claims 1 to 3, wherein the optical fiber has an optical transmission loss in water of less than 20% of the incident light amount.

7. The optical fiber is fitted with a reinforcing member that maintains a relative inclination angle between its tip and base ends, and the irradiation portion of the optical fiber is exposed on the tip side of the reinforcing member, as described in any one of claims 1 to 3.

8. An optical irradiation probe having a heat-resistant optical fiber whose tip is an irradiation part that emits light, wherein a target to be treated is brought into contact with the irradiation part of the optical fiber and surgical treatment is performed with the irradiated light, wherein a reinforcing member is attached to the outer circumference of the optical fiber, the irradiation part is exposed on the tip side of the reinforcing member, and the tip portion of the optical fiber is held in a bent shape in which the tip side is inclined laterally with respect to the base side by being fitted from one side into a recess formed in the reinforcing member.

9. The optical irradiation probe according to claim 8, wherein, in the mounting portion of the reinforcing member, the outer surface of the optical fiber is fitted into the groove over a range exceeding half a circumference.

10. An optical irradiation probe having a heat-resistant optical fiber whose tip is an irradiation part that emits light, wherein a target to be treated is brought into contact with the irradiation part of the optical fiber and surgically treated with the irradiated light, wherein the tip side of the optical fiber extends at a laterally inclined angle with respect to the base side, the optical fiber is fitted with a reinforcing member that maintains the relative inclination angle between the tip side and the base side, the irradiation part is exposed on the tip side of the reinforcing member, and the reinforcing member is formed of an opaque material.

11. The optical irradiation probe according to any one of claims 8 to 10, wherein a protective jacket for protecting the optical fiber is attached to the base end portion of the optical fiber in an external state, and the reinforcing member is connected to the tip side of the protective jacket.

12. The optical irradiation probe according to any one of claims 8 to 10, wherein the surface of the reinforcing member on the optical fiber side is provided with a heat dissipation layer having a higher thermal conductivity than the reinforcing member.

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