JP7824800B2 - medical devices - Google Patents

Description

The present invention relates to a medical device used in treatment by irradiating a lesion with light.

Photodynamic therapy and photoimmunotherapy, which use photoreactive substances with tumor cell selectivity, are known as localized cancer treatments (see, for example, Patent Document 1). In particular, treatments using photosensitive substances (hydrophilic phthalocyanines) can specifically destroy target cells without destroying non-target cells such as normal cells by irradiating the photosensitive substance accumulated in tumors with excitation light (e.g., near-infrared light). This is expected to achieve high therapeutic efficacy while reducing side effects (see Patent Document 2).

Japanese Patent Application Laid-Open No. 2000-7693 Japanese Patent Application Laid-Open No. 2020-138940

When irradiating a lesion with light during treatment, the light irradiation conditions are closely related to the treatment area and therapeutic effect, so maintaining appropriate light irradiation conditions is necessary to ensure reliable treatment. However, in actual treatment, it is expected that it will be difficult to maintain appropriate excitation light irradiation conditions for a certain period of time due to spatial constraints, constraints due to position, and restrictions on the irradiation area due to the light irradiation method. For this reason, there is a demand for techniques and devices that can maintain appropriate light irradiation conditions.

The present invention has been made to solve the above-mentioned problems, and aims to provide a medical device that can maintain appropriate irradiation of excitation light onto the lesion.

The medical device of the present invention, which achieves the above-mentioned object, is a medical device that irradiates excitation light onto a photosensitive substance accumulated in a tumor to destroy tumor cells, and comprises: a long shaft portion having a tip portion and a base portion; a light emitting portion located at the tip portion of the shaft portion and having a light emitting surface that emits excitation light for the photosensitive substance; a housing connected to the base end portion of the shaft portion; and an attitude adjustment portion that changes the attitude of the light emitting portion, and has two clamping portions located at the tip portion of the shaft portion that can be moved closer to or farther apart relative to each other, the attitude adjustment portion having a clamping operation portion that moves the two clamping portions closer to or farther apart, the light emitting surface being located on at least one of the opposing surfaces of the two clamping portions, and the clamping operation portion having an engagement portion that can release the relative positions of the two clamping portions so that the distance between the two clamping portions is temporarily fixed at a predetermined interval .

The medical device configured as described above can change the position of the light emitting surface located at the tip of the shaft by operating the position adjustment unit, allowing the light emitting surface to be brought into appropriate contact with the living body and stably maintaining the irradiation of excitation light onto the lesion.

The light emitting section has a light transmitting section having the light emitting surface and a support section that supports the light transmitting section, and the support section may scatter, diffuse, or reflect light from the light transmitting section side. This allows the light emitting section to efficiently emit excitation light from the light emitting surface.

The attitude adjustment unit may have a rotation operation unit that rotates the light emitting unit. This allows the light emitting unit to be rotated by operating the rotation operation unit, changing the attitude of the light emitting surface and bringing the light emitting surface into appropriate contact with the living body.

The medical device may have two clamping sections disposed at the tip of the shaft section that can move closer to or farther away from each other, the attitude adjustment section may have a clamping operation section that moves the two clamping sections closer to or farther away from each other, and the light emitting surface may be disposed on at least one of the opposing surfaces of the two clamping sections. This allows the lesion to be clamped between the light emitting surfaces that irradiate excitation light, and the light emitting surfaces to be fixed to the lesion, ensuring that the excitation light is irradiated to the lesion.

The light emitting surface may be located on one of the clamping sections, and a light detecting unit capable of detecting light intensity may be located on the other of the clamping sections. This allows excitation light to be reliably irradiated onto the lesion from one of the clamping sections, while the fluorescence emitted by the photosensitive substance exposed to the excitation light is detected by the light detecting unit located on the other clamping section, making it possible to recognize the progress of tumor cell destruction.

The clamping operation unit may have an engagement unit that can releasably engage the relative positions of the two clamping units. This improves operability because the surgeon does not need to use their own strength to maintain the temporarily fixed position of the two clamping units.

The clamping operation unit may have a locking unit capable of fixing the relative positions of the two clamping units, whereby the surgeon can fix the positions of the two clamping units with the locking unit, and can easily maintain the state in which the light emitting surface is in contact with the living body.
The engaging portion may have a plurality of gear-like engaging teeth, and the housing may have engaging claws that can engage with the engaging teeth, and the engaging teeth may engage with the engaging claws of the housing at predetermined angles, thereby temporarily fixing the spacing between the two clamping portions at predetermined intervals.
The outer surfaces of the housing and the operating clamping portion may be provided with scales that allow the relative positions of the two clamping portions to be grasped.
The clamping operation unit may be provided with a locking portion having a locking claw that can engage with the front engagement teeth, and the clamping operation unit may become inoperable when the locking claw is inserted between the engagement teeth of the engagement portion.
The locking claw may be positioned inside the housing so that it can engage with and disengage from the engagement portion, and a portion of the locking portion may protrude outside the housing so that it can be operated from outside the housing and slid relative to the housing.
The two clamping sections may be capable of moving relatively closer to or farther away from each other while maintaining a parallel state by operating the clamping operation section.

FIG. 1 is a perspective view showing a medical device according to a first embodiment. FIG. 2 is a perspective view of the vicinity of a light emitting portion of the medical device. FIG. 2 is a plan view of the vicinity of a light emitting portion of the medical device. 4A and 4B are views showing the vicinity of the light emitting portion of the medical device, in which (A) is a longitudinal cross-sectional view taken along line AA in FIG. 3, and (B) is a transverse cross-sectional view taken along line BB in FIG. 10A to 10D are cross-sectional views showing modified examples of the light emitting portion of a medical device, where (A) shows a first modified example, (B) shows a second modified example, (C) shows a third modified example, and (D) shows a fourth modified example. 10A and 10B are longitudinal cross-sectional views showing modified examples of the light emitting portion of a medical device, where (A) shows the fifth modified example, (B) shows the sixth modified example, (C) shows the seventh modified example, (D) shows the eighth modified example, and (E) shows the ninth modified example. 10A and 10B are plan views showing modified examples of the light emitting portion of the medical device, where FIG. 10A shows a tenth modified example, and FIG. 10B shows an eleventh modified example. 12A and 12B are cross-sectional views showing a twelfth modified example of a medical device, in which (A) shows the light emitting portion in its natural state, and (B) shows the light emitting portion housed in a tubular portion. FIG. 10 is a longitudinal cross-sectional view showing a state in which excitation light is irradiated onto a lesion from a light emitting surface. FIG. 10 is a perspective view showing a medical device according to a second embodiment. 1A and 1B are plan views of the vicinity of the clamping parts, in which FIG. 1A shows a state in which the two clamping parts are spaced apart, and FIG. 1B shows a state in which the two clamping parts are close to each other. 1A and 1B are diagrams showing an example of a movement mechanism, in which FIG. 1A shows a state in which two clamping units are spaced apart, and FIG. 1B shows a state in which the two clamping units are close to each other. FIG. 10A and 10B are plan views showing the vicinity of the clamping portion of modified examples of the medical device, where (A) shows a thirteenth modified example, and (B) shows a fourteenth modified example. 10A and 10B are plan views showing the vicinity of the clamping portion of modified examples of the medical device, where (A) shows the 15th modified example, (B) shows the 16th modified example, and (C) shows the 17th modified example. FIG. 2 is a plan view showing a state in which excitation light is irradiated onto a lesion from a light exit surface.

Embodiments of the present invention will be described below with reference to the drawings. Note that dimensions in the drawings may be exaggerated for the sake of explanation and may differ from the actual dimensions. Furthermore, in this specification and drawings, components that have substantially the same functional configuration will be assigned the same reference numerals to avoid redundant description. In this specification, the side of the device that comes into contact with the living body will be referred to as the "distal side," and the side that is operated will be referred to as the "proximal side."

First Embodiment
The medical device 10 according to the first embodiment is used to treat tumors. While the type of tumor is not particularly limited, it can be applied to gynecological cancers such as uterine cancer and ovarian cancer. The medical device 10 is used in photoimmunotherapy, which destroys target cells by irradiating a photosensitive substance accumulated in tumor cells with near-infrared light, which is the excitation light for the photosensitive substance. The target cells are tumor cells, such as cancer cells or cells of precancerous lesions. In this treatment method, an antibody that specifically binds only to a unique antigen on the surface of tumor cells and a photosensitive substance bound to the antibody are used as drugs. The antibody is not particularly limited, but examples include panitumumab, trastuzumab, HuJ591, pertuzumab, lapatinib, palbociclib, and olaparib. The photosensitive substance is, for example, but not limited to, hydrophilic phthalocyanine, a substance that responds to near-infrared light with a wavelength of approximately 700 nm (IR700). When IR700 is exposed to near-infrared light with a wavelength of approximately 660 to 740 nm, the ligands of the functional groups that ensure its water solubility are cleaved, causing a structural change from water solubility to hydrophobicity. This structural change pulls out membrane proteins, creating holes in the cell membrane and allowing water to enter the cell, rupturing and destroying tumor cells. IR700 is also excited by near-infrared light and emits fluorescence at a wavelength different from the excitation wavelength. For example, when IR700 is excited by near-infrared light with a wavelength of 689 nm, it emits fluorescence at a wavelength of 704 nm. IR700 undergoes a structural change while emitting fluorescence due to a photoreaction, and once it has destroyed tumor cells and fulfilled its role as a drug, it ceases to emit fluorescence.

The medical device 10 of this embodiment is configured to be suitable for treatments that approach tumor cells via laparotomy or laparoscopy. As shown in FIG. 1, the medical device 10 of this embodiment includes a light irradiation unit 20 that irradiates excitation light for a photosensitizer, a housing 40 that is manually operated by the surgeon, a shaft unit 30 that extends from the housing 40 toward the tip, and a tubular unit 50 that extends from the housing 40 toward the tip and covers the shaft unit 30. The medical device 10 also includes an attitude adjustment unit 11 that adjusts the attitude of the light irradiation unit 20. A rotation operation unit 51 that constitutes the attitude adjustment unit 11 is provided at the base end of the tubular unit 50, allowing the shaft unit 30 to be rotated around its axis.

As shown in Figures 2 to 4, the light irradiation unit 20 has a long irradiation optical waveguide 21 and a light emission unit 22 located at the tip side of the irradiation optical waveguide 21. The irradiation optical waveguide 21 is a long wire that propagates light. The irradiation optical waveguide 21 is formed, for example, from a single optical fiber. However, the irradiation optical waveguide 21 may also be formed from multiple optical fibers. The irradiation optical waveguide 21 is disposed inside the shaft unit 30, and the base end of the irradiation optical waveguide 21 is connectable to an optical output device (not shown) that outputs light. The irradiation optical waveguide 21 can receive near-infrared rays, which are excitation light for photosensitizers, from the optical output device and propagate the near-infrared rays to the light emission unit 22. However, the irradiation optical waveguide 21 may also be formed from an optical waveguide other than an optical fiber.

The light-emitting section 22 has a light-emitting section 23, a light-transmitting section 25 with a light-emitting surface 24 that receives light from the light-emitting section 23 and emits light in a planar manner, and a support section 26 that supports the light-transmitting section 25 so that the light-emitting surface 24 is exposed to the outside.

The light-emitting unit 23 is a cylindrical diffuser that is connected to the cut end of the optical fiber and diffuses the light received from the optical fiber. The light-emitting unit 23 may be formed integrally with the optical fiber that forms the irradiation optical waveguide 21 by processing the surface or interior of the optical fiber. The light-emitting unit 23 may also be the cut end of the optical fiber. The light-emitting unit 23 may also be formed by a mirror and/or lens placed on the cut end of the optical fiber. The light-emitting unit 23 may be an LED that emits light using electricity, etc. As shown in Figure 5 (A), multiple light-emitting units 23 (e.g., three) may be provided.

As shown in Figures 2 to 4, the support portion 26 is cup-shaped and accommodates the light-transmitting portion 25. The tip of the shaft portion 30 is connected to the support portion 26. The support portion 26 can rotate together with the shaft portion 30 by rotating the rotary operation unit 51. The support portion 26 accommodates the light-emitting portion 23 and the light-transmitting portion 25, with the light-emitting surface 24 of the light-transmitting portion 25 exposed to the outside. The shape of the support portion 26 is not particularly limited, as long as the light-emitting surface 24 of the light-transmitting portion 25 it supports is exposed to the outside and can be brought into contact with a living body. The inner surface of the support portion 26 may be coated with a scattering (diffusion) coating to diffuse (scatter) the light emitted by the light-emitting portion 23. In the scattering (diffusion) coating, the inner surface of the support portion 26 is coated with a light-diffusing or light-scattering material. Examples of the light-diffusing or light-scattering material include TiO microparticles and PS microparticles. In the diffusion (scattering) coating, the inner surface of the support portion 26 itself may be formed with minute irregularities. The inner surface of the support portion 26 may be coated with a reflective coating that specularly reflects the excitation light emitted by the light-emitting portion 23, or the inner surface structure of the support portion 26 itself may be a reflector. The inner surface of the support portion 26 preferably has a curved shape that is concave toward the light-emitting surface 24 so that the excitation light emitted by the light-emitting portion 23 can be efficiently and uniformly reflected toward the light-emitting surface 24. For example, as shown in FIG. 4A , the inner surface of the support portion 26 has a curved shape in a cross section perpendicular to the axis of the shaft portion 30. As shown in FIG. 5B , the inner surface of the support portion 26 may have a shape with corners rather than a curved shape in a cross section perpendicular to the axis of the shaft portion 30, and the cross section of the light-transmitting portion 25 may be rectangular. Alternatively, as shown in FIG. 6A , the inner surface of the support portion 26 may have a curved shape in a cross section parallel to the axis of the shaft portion 30. Alternatively, the inner surface of the support portion 26 may have a curved shape that is concave toward the light exit surface 24 in both a cross section perpendicular to the axis of the shaft portion 30 and a cross section parallel to the axis of the shaft portion 30. The material of the support portion 26 preferably has a certain degree of strength, and suitable materials for this purpose include metals such as stainless steel and resins such as ABS resin.

The light-transmitting portion 25 is formed from a transparent or translucent material that can transmit light. The light-transmitting portion 25 is housed inside the support portion 26. As shown in Figures 2 to 4, the light-transmitting portion 25 has a housing hole 27 that houses the light-emitting portion 23. The light-transmitting portion 25 is not like a balloon that expands and contracts as liquid flows in and out of it, but is formed from a solid with a structure that prevents material from flowing in and out due to expansion and contraction. The light-transmitting portion 25 has a light-emitting surface 24 on the surface corresponding to the opening of the support portion 26. The light-emitting portion 23 is inserted into the housing hole 27, which can receive light from the light-emitting portion 23 and emit it from the light-emitting surface 24. The gap between the housing hole 27 and the light-emitting portion 23 is preferably filled with a material (e.g., gel) with a refractive index that matches or is close to that of the light-transmitting portion 25. This prevents light emitted from the light-emitting portion 23 from being reflected without entering the light-transmitting portion 25. The light-transmitting portion 25 is made of a transparent or translucent material, and suitable materials include resins such as acrylic, polycarbonate, PET, and polystyrene, elastomers such as silicone, TPU, TPE, and PVC, and glass. The material forming the light-transmitting portion 25 may be either hard or soft, but using a soft material reduces the risk of damaging the surface of the living body.

The light-transmitting portion 25 may be made of the transparent or translucent material described above, mixed with a light-diffusing or light-scattering material that diffuses or scatters light. Examples of the light-diffusing or light-scattering material include TiO microparticles and PS microparticles. The light-diffusing or light-scattering material may also be air bubbles. Alternatively, the light-transmitting portion 25 may have minute irregularities formed on the contact surface with the support portion 26 or on the light-emitting surface 24 that diffuses or scatters light.

The light emitting surface 24 of the light transmitting portion 25 is a flat surface that emits light from the surface. The light emitting surface 24 emits excitation light in a direction approximately perpendicular to the axis of the shaft portion 30. The light emitting surface 24 comes into close contact with the lesion and emits the excitation light directly to the lesion. The area of the light emitting surface 24 is, for example, 200 mm ² to 800 mm ^2. As an example, the length of the light emitting surface 24 along the axis of the shaft portion 30 is 20 mm to 40 mm, and the width in the direction perpendicular to the axis of the shaft portion 30 is 10 mm to 20 mm.

Note that at least a portion of the light emitting surface 24 does not have to be flat. For example, as in the modified example shown in Figure 5(C), the light emitting surface 24 may have a groove-shaped recess 28 formed in the center of the light emitting surface 24 in a direction perpendicular to the axis of the shaft portion 30, extending along the axis of the shaft portion 30. Alternatively, as in the modified example shown in Figure 6(B), the light emitting surface 24 may have a groove-shaped recess 28 formed in the center of the light emitting surface 24 in a direction perpendicular to the axis of the shaft portion 30, extending along the axis of the shaft portion 30. If the light emitting surface 24 has the recess 28, it is easy to position it relative to the raised lesion, and the light transmitting surface can easily come into close contact with the raised lesion, allowing the excitation light to be efficiently irradiated onto the lesion. Furthermore, the center of the light emitting surface 24 may have an overall concave shape.

Also, as shown in the modified example in Figure 5(D), the light emitting surface 24 may be convex. This makes it easy to position the light emitting surface 24 relative to the recessed area at the base of the raised lesion, allowing the excitation light to be efficiently irradiated onto the lesion.

The light-transmitting portion 25 having the convex light-emitting surface 24 may also be flexible. This allows the light-emitting surface 24 to be pressed against the raised lesion and deformed to fit the shape of the lesion. This makes it easier for the light-emitting surface 24 to come into close contact with the raised lesion, allowing the excitation light to be efficiently irradiated onto the lesion.

Alternatively, both the support portion 26 and the light-transmitting portion 25 may be flexible. For example, the support portion 26 may be made of a flexible white silicone resin with high reflectivity, and the light-transmitting portion 25 may be made of a flexible transparent silicone resin.

Also, as in the modified example shown in Figure 6(C), the light-transmitting section 25 may not have a storage hole 27 formed therein, and light may be incident from the light-emitting section 23, which is the end of the irradiation optical waveguide 21. As in the modified example shown in Figure 6(D), a lens 29 to assist in diffusion may be provided at the end of the irradiation optical waveguide 21. In these configurations where no storage hole is provided, it is preferable that the inner surface of the light-transmitting section 25 or the support section 26 have a structure that diffuses or scatters light as described above.

Also, as in the modified example shown in Figure 6 (E), the light-transmitting portion 25 may have a housing hole 27 formed along the axis of the shaft portion 30 up to approximately the center of the light-transmitting portion 25. The light-emitting portion 23 is a cut end facing the inner surface of the support portion 26 at approximately the center of the light-transmitting portion 25, or a lens 29 connected to the cut end. As a result, light emitted from the light-emitting portion 23 is irradiated onto the inner surface of the support portion 26 at the center of the light-transmitting portion 25, reflected and diffused (scattered) on the inner surface, and emitted uniformly from the light-emitting surface 24. If the light-transmitting portion 25 contains a light-scattering material or a light-diffusing material, the light emitted from the light-emitting surface 24 is further uniformed.

Furthermore, the light exit surface 24 and the surrounding support portion 26 do not have to be rectangular, as in the modified example shown in Figure 7(A), and may be circular or elliptical, for example.

Also, the light-transmitting portion 25 may be formed with a curved accommodation hole 27, as in the modified example shown in Figure 7 (B). The light-emitting portion 23 is a cylindrical diffuser that curves inside the accommodation hole 27. This allows the light-emitting portion 23 to be arranged over a wide area of the light-transmitting portion 25, allowing excitation light to be emitted uniformly from the light-emitting surface 24.

Also, as shown in a modified example in FIG. 8(A), the medical device 10 may have a flat support portion 26 and a flat light-transmitting portion 25 arranged to overlap the support portion 26. The support portion 26 has a groove-shaped bending guide portion 26A that facilitates bending, formed along the axis of the shaft portion 30 at approximately the center of the surface of the support portion 26 opposite the surface that contacts the light-transmitting portion 25. An elastically deformable shape-retaining portion 26B is sandwiched and arranged between the contact surface of the support portion 26 and the light-transmitting portion 25. The shape-retaining portion 26B is, for example, a shape-memory alloy such as a Ni-Ti alloy. It is preferable that the shape-retaining portion 26B be arranged so as to surround the vicinity of the outer periphery of the contact surface of the support portion 26 and the light-transmitting portion 25. As shown in FIG. 8(B), the support portion 26 and the light-transmitting portion 25 can be bent along the groove-shaped bending guide portion 26A to be deformed into an elongated shape. The support section 26 and the light-transmitting section 25 are deformed into an elongated shape and transported to the vicinity of the lesion while housed inside the tubular section 50, and then released from the tubular section 50, where they can return to their original shape. At this time, the elastically deformed shape-retaining section 26B elastically returns to its original shape, making it easy for the support section 26 and the light-transmitting section 25 to return to their original shape. Note that the bend-inducing section 26A and the shape-retaining section 26B do not necessarily have to be provided.

As shown in FIG. 1, the housing 40 has a housing main body 55 provided with a gripping portion 52 that is held by the surgeon, an advance/retract movement control portion 53 that the surgeon uses to control the protrusion state of the shaft portion 30 from the tubular portion 50, and an irradiation control portion 54 that the surgeon uses to control the emission of excitation light from the light emitting portion 22.

The advance/retract movement control unit 53 is rotatably connected to the housing body 55. The advance/retract movement control unit 53 is connected to the base end of the shaft portion 30 inside the housing body 55. The shaft portion 30 is rotatably connected to the advance/retract movement control unit 53 so that rotation about its axis is not hindered. When the surgeon moves the advance/retract movement control unit 53 while holding the grip portion 52, the shaft portion 30 can move forward and backward along its axis. Therefore, by operating the advance/retract movement control unit 53, the surgeon can make the shaft portion 30 appear and disappear from the tip of the tubular portion 50. The shaft portion 30 can also rotate by receiving a rotational force from the rotation control unit 51.

When the surgeon operates the irradiation operation unit 54, the light output unit 22 outputs excitation light from an optical output unit (not shown) within the housing 40 to the irradiation optical waveguide 21. Note that the optical output unit may also be located outside the housing 40.

The shaft portion 30 protruding from the tubular portion 50 has a shape that is curved in one direction. This allows the light emitting portion 22 to be directed in various directions by operating the rotation operation portion 51 to rotate the shaft portion 30 around its axis. The shaft portion 30 is made of a deformable material, and can assume a linear shape when stored in the tubular portion 50. The shaft portion 30 can be curved by operating the advance/retract movement operation portion 53 to cause the curved portion of the shaft portion 30 to protrude from the tubular portion 50.

The rotation operation unit 51 that rotates the light emitting unit 22, the advance/retract movement operation unit 53 that moves the light emitting unit 22 forward and backward, and the advance/retract movement operation unit 53 (bending operation unit) that bends the shaft unit 30 constitute the attitude adjustment unit 11 that adjusts the attitude of the light emitting unit 22.

The medical device 10 of this embodiment irradiates excitation light by bringing the surface-emitting light-emitting light exit surface 24 into contact with the living body, making it suitable for use on elevated or infiltrated lesions.

Next, we will explain a treatment method using the medical device 10 according to the first embodiment.

First, the photosensitive substance is administered into the body. The method for administering the photosensitive substance into the body is not particularly limited as long as it can reach the tumor cells, but an example would be intravascular administration, which in this embodiment is intravenous administration. Approximately 12 to 36 hours after intravenous administration, light irradiation treatment is performed using the medical device 10 of this embodiment.

In this embodiment, the surgeon approaches the lesion via laparotomy or laparoscopy, as described above. The surgeon approaches the lesion using an endoscope. The surgeon inserts the tubular portion 50, which houses the distal end portion having the light-emitting surface 24 of the medical device 10, into the living body. Once the distal end reaches the vicinity of the lesion, the surgeon operates the advance/retract operation unit 53 to protrude the shaft portion 30, support portion 26, and light-emitting portion 22 from the tubular portion 50. The surgeon then operates the rotation operation unit 51 to change the orientation of the support portion 26, bringing the light-emitting surface 24 of the light-transmitting portion 25 supported by the support portion 26 into contact with the periphery of the lesion L, as shown in FIG. 9 . This positions the light-emitting surface 24 so that it faces the lesion L. By maintaining the light-emitting surface 24 in intimate contact with the living body, a constant distance can be maintained between the lesion L and the light-emitting surface 24. In this state, the surgeon operates the light output device and/or the irradiation operation unit 54 of the housing 40 to supply excitation light to the light output unit 22. This allows excitation light to be irradiated onto the lesion L from the light output surface 24 of the light output unit 22.

When excitation light is applied, it reaches the photosensitive substance that has accumulated in the tumor. This causes a chemical change in the photosensitive substance, which is then excited by the excitation light, and a structural change in the photosensitive substance causes holes to form in the cell membrane. This destroys the tumor cells that are exposed to the excitation light.

While irradiating excitation light from the light irradiation unit 20, the surgeon can confirm the fluorescence emitted by the photosensitive material excited by the excitation light. Fluorescence can be confirmed via the translucent light-transmitting unit 25 and the irradiation optical waveguide 21. That is, the irradiation light-transmitting unit 25 and the irradiation optical waveguide 21 are also used for detecting fluorescence, and the fluorescence detected via the irradiation optical waveguide 21 can be displayed, for example, on an external display device (not shown), to confirm the fluorescence. Note that, to confirm the fluorescence, a light detection unit capable of detecting light intensity may be placed inside the light-transmitting unit 25 or near the support unit 26. When detecting fluorescence, not only the fluorescence but also the excitation light can be detected, allowing the irradiation state of the excitation light to be confirmed.

When the display device determines that the fluorescence has disappeared or when a predetermined time has elapsed, the surgeon determines that the tumor cells in the area irradiated with the excitation light have been sufficiently destroyed. If other tumor cells are present, the surgeon places the light emitting surface 24 in contact with the periphery of another lesion L and irradiates the area with the excitation light.

As described above, the medical device 10 according to this embodiment is a medical device that irradiates excitation light onto photosensitive substances accumulated in tumors to destroy tumor cells, and includes a long shaft portion 30 with a distal end and a proximal end, a light emitting portion 22 disposed at the distal end of the shaft portion 30 and having a light emitting surface 24 that emits excitation light for the photosensitive substance, a housing 40 connected to the proximal end of the shaft portion 30, and an attitude adjustment portion 11 that changes the attitude of the light emitting portion 22.

The medical device 10 configured as described above can change the position of the light emitting surface 24 located at the tip of the shaft portion 30 by operating the position adjustment unit 11, allowing the light emitting surface 24 to be brought into appropriate contact with the living body, and stably maintaining the irradiation state of the excitation light on the lesion L.

The light emitting section 22 has a light transmitting section 25 with a light emitting surface 24 and a support section 26 that supports the light transmitting section 25. The support section 26 scatters, diffuses, or reflects light from the light transmitting section 25 side. This allows the light emitting section 22 to efficiently emit excitation light from the light emitting surface 24.

The attitude adjustment unit 11 has a rotation operation unit 51 that rotates the light emitting unit 22. As a result, by operating the rotation operation unit 51, the light emitting unit 22 is rotated, changing the attitude of the light emitting surface 24, allowing the light emitting surface 24 to be in appropriate contact with the living body.

The posture adjustment unit 11 has a bending operation unit (advance/retreat operation unit 53) that bends the shaft unit 30. As a result, by operating the bending operation unit, the shaft unit 30 is bent, changing the posture of the light emitting surface 24, allowing the light emitting surface 24 to appropriately contact the living body.

The posture adjustment unit 11 has an advance/retract movement operation unit 53 that moves the light emitting unit 22 along the axis of the shaft unit 30. By operating the advance/retract movement operation unit 53, the light emitting unit 22 can be moved to change the posture of the light emitting surface 24, allowing the light emitting surface 24 to appropriately contact the living body.

Second Embodiment
The medical device 10 according to the second embodiment differs from the first embodiment in that it has two clamping portions 60 that clamp the lesion L, and a light emitting portion 22 is provided on at least one of the clamping portions 60.

As shown in Figures 10 to 13, the medical device 10 has two clamping units 60 connected to the tip of the shaft unit 30, and a clamping operation unit 70 mounted on the housing 40 for operating the two clamping units 60. The clamping operation unit 70 constitutes part of the attitude adjustment unit 11. The two clamping units 60 are substantially parallel and can be moved closer to or farther apart relative to each other. The two clamping units 60 can be moved closer to or farther apart relative to each other while maintaining their parallel state by a moving mechanism 61, such as a parallel crank mechanism (see Figure 12). The moving mechanism 61 is connected to a manipulation wire 62 that moves forward and backward by operating the clamping operation unit 70 mounted on the housing 40. As the manipulation wire 62 moves along the axis of the shaft unit 30, the moving mechanism 61 can move the two clamping units 60 closer to or farther apart relative to each other while maintaining their parallel state.

A light-transmitting portion 25 having a light-emitting surface 24 and a support portion 26 that supports the light-transmitting portion 25 are arranged on one side of the clamping portions 60. The light-emitting surface 24 is arranged on the opposing side of the two clamping portions 60. The size of the light-emitting surface 24 is, for example, 20 mm in length along the axis of the shaft portion 30 and 10 mm in length perpendicular to the axis of the shaft portion 30. The distance between the two clamping portions 60 can be changed, for example, between 0 mm and 20 mm.

The clamping operation unit 70 has a structure in which the two clamping units 60 provide a tactile feedback or a temporary stop at a predetermined interval (e.g., 5 mm). For example, the clamping operation unit 70 has an engagement unit 72 with multiple gear-like engagement teeth 71 that can engage with the housing 40 at predetermined angles, and the housing body 55 has an engagement claw 73 that can engage with one of the engagement teeth 71 on the engagement unit 72. The engagement claw 73 is elastically deformable. The engagement teeth 71 deform and overcome the engagement claw 73, allowing the clamping operation unit 70 to provide a tactile feedback and a temporary stop. The exterior surfaces of the housing body 55 and the operating clamping unit 60 are marked with scales 74 that allow the surgeon to grasp their relative positions. This allows the surgeon to recognize the distance between the two clamping units 60. The clamping operation unit 70 also has a locking unit 76 with a locking claw 75 that can engage with one of the engagement teeth 71 on the engagement unit 72. The locking claw 75 is rigid and is disposed inside the housing body 55 so that it can engage with and disengage from the engaging portion 72. The locking portion 76 is slidable relative to the housing body 55, with a portion of it protruding outside the housing body 55. The surgeon can operate the locking portion 76 from outside the housing body 55 to slide it relative to the housing body 55. This causes the locking claw 75 to be inserted between the engaging teeth 71 of the engaging portion 72, rendering the operating clamping portion 60 inoperable and maintaining the distance between the two clamping portions 60. This makes it easy to maintain the light emitting surface 24 in contact with the living body. Note that the structure that provides a tactile response and the structure that temporarily stops the clamping operating portion 70 are not limited to the structures described above.

The two clamping sections 60 do not have to be able to move toward or away from each other in parallel. For example, as shown in Figure 14(A), the operating wire 62 may move along the axis of the shaft section 30, causing the two curved clamping sections 60 to move toward or away from each other while tilting and opening and closing.

Furthermore, the movement mechanism 61 that moves the two clamping units 60 toward and away from each other in parallel may be a mechanism in which only one of the clamping units 60 moves, as shown in Figure 14 (B), for example.

Furthermore, the support portion 26 and the light-transmitting portion 25 may be provided on both clamping portions 60, as in the modified example shown in Figure 15 (A). This allows the excitation light to be effectively irradiated onto the lesion L.

Also, as shown in Figure 15 (B), the irradiation optical waveguide 21 may be led out from the outside of the clamping portion 60.

Alternatively, as shown in Figure 15 (C), the light emitting surface 24 may be located on one clamping unit 60, and a light detecting unit 80 capable of detecting light intensity may be located on the other clamping unit 60. The light detecting unit 80 can detect excitation light that has passed through the lesion L and/or fluorescence emitted by the photosensitive substance excited by the excitation light. Note that the location of the light detecting unit 80 is not particularly limited as long as it can detect fluorescence emitted by the photosensitive substance.

In addition, a pressure sensor that detects the clamping force may be provided in at least one of the two clamping sections 60. This allows the surgeon to recognize the clamping force, making it easier to maintain the light emitting surface 24 in contact with the living body.

The treatment method using the medical device 10 of the second embodiment is similar to the treatment method using the medical device 10 of the first embodiment in the steps prior to the light irradiation treatment. In this embodiment, the surgeon approaches the lesion L via laparotomy or laparoscopy. The surgeon inserts the tubular body housing the clamping units 60 into the living body. When the clamping units 60 reach the vicinity of the lesion L, the surgeon protrudes the clamping units 60 from the tubular units 50 and operates the clamping operation units 70 to separate the two clamping units 60. Next, the surgeon operates the rotation operation units 51 to change the orientation of the light emitting surfaces 24, and brings the light emitting surfaces 24 of the clamping units 60 into contact with the periphery of the lesion L. Next, while checking the scale 74, the surgeon operates the clamping operation units 70 to clamp the raised lesion L with the clamping units 60, as shown in FIG. 16 . Then, with the light emitting surface 24 in the appropriate position in contact with the raised lesion L, the operator operates the locking unit 76 to fix the position of the two clamping units 60. This allows the operator to maintain the light emitting surface 24 in contact with the living body. In this state, the operator operates the irradiation operation unit 54 of the housing 40 to supply excitation light to the light irradiation unit 20. This allows the excitation light to be irradiated from the light emitting surface 24 to the lesion L. Subsequent steps are the same as those in the treatment method of the first embodiment.

As explained above, the medical device 10 according to the second embodiment has two clamping sections 60 that are arranged at the tip of the shaft section 30 and can move closer to or farther away from each other, the attitude adjustment section 11 has a clamping operation section 70 that moves the two clamping sections 60 closer to or farther away from each other, and the light emitting surface 24 is arranged on at least one of the opposing surfaces of the two clamping sections 60. This allows the lesion L to be clamped between the light emitting surfaces 24 that irradiate excitation light, and the light emitting surfaces 24 to be fixed to the lesion L, ensuring that the excitation light is irradiated onto the lesion L.

Alternatively, the light emitting surface 24 may be located on one side of the clamping unit 60, and a light detection unit 80 capable of detecting light intensity may be located on the other side of the clamping unit 60. This allows excitation light to be reliably irradiated onto the lesion L from one clamping unit 60, while the light detection unit 80 detects fluorescence emitted by the photosensitive substance exposed to the excitation light from the other clamping unit 60, making it possible to recognize the progress of tumor cell destruction.

The clamping operation unit 70 also has an engagement unit 72 that can releasably engage the relative positions of the two clamping units 60. This eliminates the need for the surgeon to maintain the temporarily fixed positions of the two clamping units 60 with their own strength, improving operability.

The clamping operation unit 70 also has a locking unit 76 that can fix the relative positions of the two clamping units 60. This allows the surgeon to fix the positions of the two clamping units 60 using the locking unit 76, making it easy to maintain the light emitting surface 24 in contact with the living body.

The present invention is not limited to the above-described embodiments, and various modifications may be made by those skilled in the art within the technical spirit of the present invention. For example, the various configurations described in this specification may be combined as appropriate.

REFERENCE SIGNS LIST 10 Medical device 11 Attitude adjustment section 20 Light irradiation section 21 Irradiation optical waveguide 22 Light emission section 23 Light emitting section 24 Light emission surface 25 Light transmission section 26 Support section 27 Storage hole 28 Recessed section 29 Lens 30 Shaft section 40 Housing 50 Tubular section 51 Rotation operation section 52 Grip section 53 Advance/retract movement operation section (bending operation section)
54 Irradiation operation unit 55 Housing body 60 Clamping unit 61 Moving mechanism 62 Operation wire 70 Clamping operation unit 71 Engagement teeth 72 Engagement unit 73 Engagement claw 74 Scale 75 Locking claw 76 Locking unit 80 Light detection unit

Claims (10)

A medical device that destroys tumor cells by irradiating a photosensitive substance accumulated in a tumor with excitation light,
an elongated shaft portion having a distal end and a proximal end;
a light emitting portion disposed at a tip end of the shaft portion and having a light emitting surface that emits excitation light for the photosensitizer;
a housing connected to a base end of the shaft portion;
an attitude adjustment unit that changes the attitude of the light emitting unit ,
two clamping portions disposed at the tip of the shaft portion and capable of moving closer to or farther away from each other;
the attitude adjustment unit has a clamping operation unit that moves the two clamping units closer to or farther apart,
the light exit surface is disposed on at least one of the opposing surfaces of the two clamping portions,
The clamping operation unit is a medical device having an engagement unit that can release the relative positions of the two clamping units so that the spacing between the two clamping units is temporarily fixed at predetermined intervals . the light emitting portion includes a light transmitting portion having the light emitting surface;
a support portion that supports the light transmitting portion,
The medical device according to claim 1 , wherein the support portion scatters, diffuses, or reflects light from the light-transmitting portion side. The medical device described in claim 1 or 2, wherein the attitude adjustment unit has a rotation operation unit that rotates the light emission unit. The light exit surface is disposed on one of the clamping portions,
The medical device according to any one of claims 1 to 3, wherein a light detecting unit capable of detecting the intensity of light is disposed on the other of the clamping units. 5. The medical device according to claim 1, wherein the clamping operation section has a locking section that can fix the relative positions of the two clamping sections. The engaging portion has a plurality of gear-like engaging teeth,
the housing has an engagement claw that can be engaged with the engagement tooth,
A medical device according to any one of claims 1 to 4, wherein the engagement teeth engage with the engagement claws of the housing at predetermined angles, thereby temporarily fixing the spacing between the two clamping portions at predetermined intervals. The medical device according to claim 6 , wherein the outer surfaces of the housing and the operating clamping portion are provided with scales that allow the relative positions of the two clamping portions to be ascertained. the clamping operation unit includes a locking unit having a locking claw that can be engaged with the engagement teeth,
The medical device according to claim 6 or 7, wherein the clamping operation portion is rendered inoperable by the locking claw being inserted between the engagement teeth of the engagement portion. the locking claw is disposed inside the housing so as to be able to engage with and disengage from the engaging portion;
The medical device according to claim 8 , wherein a portion of the locking portion protrudes outside the housing and can be operated from outside the housing to slide relative to the housing. The medical device according to any one of claims 1 to 9, wherein the two clamping sections can be moved relatively closer to or farther apart while maintaining a parallel state by operating the clamping operation section.