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BR-112020016338-B1 - DEVICE FOR TREATING BODY TISSUE

BR112020016338B1BR 112020016338 B1BR112020016338 B1BR 112020016338B1BR-112020016338-B1

Abstract

DEVICE FOR TREATING BODY TISSUE. The invention relates to a device (17) for the treatment of body tissue, in particular, for the permanent occlusion of varicose veins, preferably in the lower limbs, varicocele and/or vascular malformations and/or for use in cosmetic surgery, preferably laser-assisted lipolysis, and/or for tumor treatment by means of laser-induced thermotherapy and/or photodynamic therapy, by means of a light diffuser (13) that circumferentially and endoluminally irradiates said tissue by laser light energy, said diffuser (13) being connected at its proximal end to a laser light energy source (10) by means of a flexible waveguide (12) comprising an optical fiber core (1) covered by an optical envelope (2) having a refractive index lower than the refractive index of the core (1), wherein, in the envelope (2) and/or in the core (1), imperfections (18) are provided, designed as recesses and adapted to direct the light, preferably, to refract and/or reflect the light propagating within the core (1) and/or its optical envelope (2) in directions, generally radial, wherein a laser light transparent cap (7) encloses the end (...).

Inventors

  • Oskars DZERINS
  • Daumants PFAFRODS

Assignees

  • SIA LIGHT GUIDE OPTICS INTERNATIONAL

Dates

Publication Date
20260310
Application Date
20190919
Priority Date
20180920

Claims (20)

  1. 1. Device (17) adapted for the treatment of body tissue, said device comprising a flexible waveguide (12) and a light diffuser (13) capable of circumferentially and endoluminally irradiating said tissue with laser light energy, said diffuser (13) being connected at its proximal end to a laser light energy source (10) through said flexible waveguide (12) comprising an optical fiber core (1) covered by an optical envelope (2) having a refractive index lower than the refractive index of the core (1), wherein, in the envelope (2), in the core (1) or in both, imperfections (18) are arranged, designed as recesses and adapted to direct the light, preferably to refract and/or reflect the light propagating within the core (1) and/or in its optical envelope (2) in generally radial directions, wherein a transparent cap (7) for laser light is arranged that encloses the distal end of the core (1) and its optical envelope (2) in a fluid-impermeable manner, characterized in that the outer surface (19) of said optical envelope (2) is fused in the region (A) between said imperfections (18) on the inner surface (21), preferably on the inner diameter of the cover (7) and in that the outer surface (19) of said optical envelope (2) that extends for a distance in front of and/or behind the region (A) endowed with the imperfections (18) is fused to the inner surface (21), preferably on the inner diameter of the cover (7).
  2. 2. Device according to claim 1, characterized in that: the outer surface (19) of said optical enclosure (2) is fused continuously, circumferentially or completely in the region (A) between said imperfections (18) to the inner surface (21), preferably to the inner diameter, of the cover (7); the outer surface (19) of said optical enclosure (2) that extends for a distance in front of and/or behind the region (A) having the imperfections (18) is fused continuously, circumferentially or completely to the inner surface (21), preferably to the inner diameter, of the cover (7); or a combination thereof.
  3. 3. Device according to claim 1, characterized in that: the outer surface (19) of said optical enclosure (2) is partially fused, preferably in a spot-like manner and/or with longitudinal welds, in the region (A) between said imperfections (18), to the inner surface (21), preferably to the inner diameter, of the cover (7); the outer surface (19) of said optical enclosure (2) that extends for a distance in front of and/or behind the region (A) having the imperfections (18) is partially fused, preferably in a spot-like manner and/or with longitudinal welds to the inner surface (21), preferably to the inner diameter, of the cover (7); or a combination thereof.
  4. 4. Device, according to any of the preceding claims, characterized in that in the fused regions (32) in which the casing (2) is fused to the cover (7), the casing (2) and the cover (7) are firmly adhered, in particular, in a material-locking manner.
  5. 5. Device, according to any of the preceding claims, characterized in that the core (1) has an outer diameter (22) between 100 and 1000 μm, preferably between 200 and 800 μm, more preferably between 300 and 700 μm and, in particular, between 350 and 600 μm.
  6. 6. Device, according to any of the preceding claims, characterized in that the casing (2) has an outer diameter (23) between 110 and 1200 μm, preferably between 250 and 850 μm, more preferably between 350 and 750 μm and, in particular, between 400 and 650 μm.
  7. 7. Device, according to any of the preceding claims, characterized in that the sheath thickness (24) of the envelope (2) is between 1% and 40%, preferably between 5% and 20%, of the outer diameter (22) of the core (1).
  8. 8. Device, according to any of the preceding claims, characterized in that a protective sheath (25) is preferably present at the distal end of the waveguide (12), in particular, wherein the protective sheath (25) comprises at least one buffer layer (3) adjacent to the optical envelope (2) of the core (1), an outer sheath (14) or a combination thereof.
  9. 9. Device according to claim 8, characterized in that the protective sheath (25), in particular the outer sheath (14), is joined to the cover (7) and/or is designed as a plastic coating, preferably extruded.
  10. 10. Device according to claim 8 or 9, characterized in that the protective sheath (25), in particular its outer sheath (14), is at least partially removed at the distal end of the waveguide (12) so as to expose the core (1) and its optical envelope (2).
  11. 11. Device according to any one of claims 8 to 10, characterized in that the imperfections (18) extend into the casing (2), preferably to expose the core (1), into the core (1) or both.
  12. 12. Device, according to any of the preceding claims, characterized in that the imperfections (18) are designed as grooves (4, 5, 40, 50, 26, 27, 28) adapted to refract and/or reflect light propagating within the core (1) and its optical envelope (2) in directions, generally radial, in particular, wherein said grooves comprise at least two spiral grooves (4, 5, 40, 50), said grooves (4, 5, 40, 50) extending through said optical envelope (2) into said core (1), wherein successive grooves (4, 5) of the respective spiral grooves are alternated along the outer surface (19) extending longitudinally from the core (1) and its optical envelope (2); said grooves comprise at least one circular and/or elliptical groove (26); said grooves comprise at least one longitudinal groove (27); said grooves comprise at least one groove similar to a point and/or broken groove (28), or a combination thereof.
  13. 13. Device, according to any of the preceding claims, characterized in that one or more of the depth (30), width (31) or length (29) of the imperfections (18), preferably of the grooves (4, 5, 40, 50, 26, 27, 28), increases in a direction towards the distal end of the nucleus (1), in particular, in which one or more of the depth (30), width (31) or length (29) of the imperfections (18) increases up to 1000%, preferably up to 800%, more preferably up to 400%, in particular, in relation to the smaller depth (30), width (31) or length (29) of the imperfections (18).
  14. 14. Device, according to any of the preceding claims, characterized in that the core material (1) contains fused silica, in particular, quartz glass; the shell material (2) contains fused silica, in particular, quartz glass; or a combination thereof; in particular, wherein the fused silica material of the core (1) differs from the fused silica material of the shell (2); and/or the fused silica material of the shell (2), of the core (1) or both is doped, more particularly, wherein the shell (2) is doped with fluorine, the core (1) is doped with germanium or both.
  15. 15. Device, according to any of the preceding claims, characterized in that the region (A) having the imperfections (18), preferably the grooves (4, 5, 40, 50, 26, 27, 28), has a length (29) between 0.1 and 30 mm, preferably between 1 and 15 mm, more preferably between 3 and 4 mm.
  16. 16. Device, according to any of the preceding claims, characterized in that the distal end of the core (1) is terminated by a reflector (6), in particular, wherein the reflector (6) is formed by the distal end of the core (1) and/or by the casing (2).
  17. 17. Device according to claim 16, characterized in that the reflector (6) has a conical shape, the angle of the reflector cone (6) being designed as a 60-degree reflecting cone.
  18. 18. Device according to claim 16, characterized in that the reflector (6) has a conical reflecting cone surface, the angle of the reflecting cone (6) being from 68 degrees to 90 degrees.
  19. 19. Device according to claim 8, characterized in that the proximal end of the cap orifice (7) is provided with a section (8) having an increased inner diameter corresponding to the outer diameter of the damping layer (3) or to the outer diameter (22) of the core (1).
  20. 20. Device according to claim 19, characterized in that the section (8) having its inner diameter increased at the proximal end of the cap (7) is glued to one or more of at least one cushioning layer (3), the core (1) or the sheath (2), in particular, wherein the glue (9) additionally produces a smooth transition between the outer surface, in particular, the outer diameter of the cap (7) and the outer sheath (14).

Description

[0001] This invention relates to a device for treating body tissue by means of a laser light diffuser that irradiates said tissue circumferentially and endoluminally with laser light. [0002] In particular, the device for body tissue treatment is intended for use in the permanent occlusion of varicose veins, preferably in the lower limbs. In addition, the device is preferably intended for use in the permanent occlusion of varicocele and/or vascular malformations. Alternatively or additionally, the device may be intended for use in cosmetic surgery, in particular as laser-assisted lipolysis, for tumor treatment, preferably by means of laser-induced thermotherapy (LITT) or photodynamic therapy (PDT). [0003] The said diffuser is connected at its proximal end to a laser light energy source via a flexible waveguide comprising an optical fiber core covered by an optical envelope having a refractive index lower than the refractive index of the core. Imperfections are provided in the envelope, in the core, or both, wherein the imperfections are adapted to direct the light, preferably to refract and/or reflect the light propagating within the core, its optical envelope, or both in generally radial directions. The imperfections are designed as recesses. [0004] The imperfections designed as recesses may extend at least through the envelope and, preferably, through the core. In particular, the imperfections designed as recesses may differ from each other, particularly with respect to depth. Preferably, at least one imperfection may extend only into the interior of the envelope, and therefore not into the core, wherein at least one additional imperfection may extend into the interior of the envelope as well as into the core. [0005] Additionally, a cap is provided, wherein the cap is transparent to laser light, enclosing the distal end of the core and its optical envelope in a fluid-impermeable manner, in particular in a liquid-impermeable manner. Laser light can pass through the optical envelope and the cap. [0006] In the medical field, diffusers are generally used at the distal end of the waveguide as a means to disperse or redirect optical power into a uniform 360-degree cylindrical output along the length of the distal end of the waveguide core. For example, this is facilitated by wrinkling the core or by machining designed imperfections such as grooves or threads into the fiber core glass deep enough to extract and disperse or redirect light traveling through the fiber core along its longitudinal geometric axis. The light emerging from the imperfections or grooves irradiates an area of tissue surrounding the diffuser with optical power, making it useful for applications such as photodynamic therapy or coagulation or ablation of hollow tissue, vessels, or organs. To protect the distal end of the core, which has its protective sheath removed, this distal end is conventionally surrounded and covered by a transparent cap to the laser light emitted by the core. [0007] In the field of lighting, it has long been known how to direct light from point light sources at one or both ends of a cylindrical rod made of refractive material and how to redirect the light propagating within the rod in radial and circumferential directions by cutting circular or spiral grooves on the outer surface of the rod as known in document FR 1 325 014. The light traveling within the rod exits through said grooves. If the light is directed to the rod from only one end, it is possible to terminate the other end with a cone reflector. In order to obtain a uniform radiation distribution along the length of the rod, it is also known how to use deeper grooves at positions on the rod further from the light sources to enhance the uniform radiation distribution. [0008] The same principle is also used in the medical field as exemplified in an embodiment of a laser light diffuser shown in Fig. 6 of document EP 0 598 984 A1. In this embodiment, angled grooves are cut into the core of a waveguide at an angle to the longitudinal geometric axis thereof. Additionally, this embodiment is provided with a cone reflector at the distal end of the core, and the core section comprising the groove as well as the cone reflector is enclosed by a laser light-transparent cover. [0009] The design of such diffusers varies depending on the desired length of the light-emitting zone and the required light uniformity, as well as the available laser light energy. [0010] In practice, it has been found that, in some cases, after treatment of the body tissue, the cap remains in the patient's body tissue, where the core and waveguide have been pulled from the body tissue. Unfortunately, the remaining cap in the body tissue is a risk for infections and therefore compromises the patient's health. Not only does the risk of infection increase due to the use of known diffusers, but also the sectioned and/or aborted cap can rupture the body tissue and consequently lead to internal bleeding.