Hand-held fibre probe for laser treatment of medical tissue, in particular for treatment of glaucoma

Abstract

The invention concerns a hand-held fibre probe (2) for use in laser treatment of medical tissue, in particular for treatment of glaucoma, and having a fibre optic cable (8), at least when assembled. The fibre probe (2) has a housing (10) with a front end (18) having an exit point for laser light. The fibre probe (2) has a front and a rear lens (16A, 16B), which can be adjusted relative to one another by the user, such that the focusing of the laser beam can be varied by varying a distance (A) between the two lenses (16A, 16B).

Description

[0001] Description Handheld fiber probe for laser treatment of medical tissue, especially for glaucoma treatment

[0002] The invention relates to a handheld fiber probe for laser treatment of medical tissue, in particular for glaucoma treatment, having the features of the preamble of claim 1.

[0003] Such a fiber probe can be found, for example, in the DE

[0004] 10 2017 104 673 A1 or EP 3 478 205 B1 .

[0005] Elevated intraocular pressure (IOP) is a major risk factor for the development of glaucoma. Therapeutic laser treatment using such fiber optic probes can reduce intraocular pressure, for example, by limiting the formation of aqueous humor and / or improving its drainage.

[0006] During laser treatment, specific tissues within the eye are targeted. The fiber optic probe is placed on the eye with a distal contact end.

[0007] DE 10 2017 104 673 A1 describes an attachment that can be screwed onto a handpiece to which a fiber optic cable is connected. A bore is formed within the attachment into which an optical fiber (optical fiber) of the fiber optic cable can be inserted. The bore ends within the attachment, so that the front contact end is closed. This prevents liquid from penetrating an annular space between the optical fiber and the bore due to capillary action during laser treatment and thus contaminating the attachment. Furthermore, an optical element for beam shaping and, for example, focusing the laser beam is mounted on the front surface of the front contact end.

[0008] EP 3 478 205 B1 also discloses a hand-held fiber probe in which a disposable attachment can be attached to a handpiece, in which an optical fiber is attached, which protrudes at the front contact end and which interacts with an optical element in the handpiece to focus the laser light.

[0009] In medical practice, the following problems have emerged when using such fiber probes - depending on the type of fiber probe:

[0010] Because the fiber optic probe is applied to the eye with a certain amount of pressure during treatment and / or high energy is delivered via the laser light, patients often find the treatment painful. This leads to such treatments often being performed under anesthesia.

[0011] Bleeding may occur during treatment, which, for example, can lead to contamination of the attachment due to capillary action, which can limit the effectiveness of the applied laser light during treatment. For example, transmission is reduced and thermal heating occurs due to undesirable absorption of laser light in the attachment.

[0012] Due to the varying anatomies of the patients, the guidance of the handheld fiber probe by medical personnel requires experienced medical personnel. In some cases, medical personnel manually place an intermediate layer, such as a thin silicone pad, between the distal contact end of the fiber probe and the eye. Based on this, the invention is based on the object of providing a handheld fiber probe for laser treatment of medical tissue, in particular for glaucoma treatment, which at least reduces some of the problems described above.

[0013] The object is achieved according to the invention by a hand-held fiber probe for laser treatment of medical tissue, and in particular for glaucoma treatment. A fiber optic cable is connected to the fiber probe, at least in the assembled state. The fiber probe has a housing with a front end, also referred to below as the distal contact end, which is designed to rest on the eye. For this purpose, the contact end has, in particular, a concavely curved surface adapted to the human eye. An exit point for laser light is formed at this front contact end. Furthermore, the fiber probe has an optic for beam shaping, in particular for focusing the laser light.This optic has at least two lenses, namely a front and a rear lens, which can be adjusted relative to each other by the user, so that by varying a distance between the two lenses the laser beam can be varied, i.e. a desired beam shaping, in particular focusing, takes place.

[0014] What is particularly noteworthy about this design is the variation of the focus and thus the change of a focal point of the laser beam by the medical staff themselves. This makes it possible for the doctor to change the focus during treatment and adapt it specifically to the anatomy of the respective patient.

[0015] The focus is varied by changing the distance between the two lenses. This is generally achieved by an adjustment mechanism that can be manually operated by the operator (doctor, medical staff) to vary the distance.

[0016] The ability for the physician to vary the focus during treatment allows the physician to precisely and accurately focus the laser energy on a specific treatment site. Manual distance adjustment, such as the sometimes practiced placement of an intermediate layer (silicone pad) between the front end and the eye, is therefore no longer necessary. This improves the usability of the fiber probe. Furthermore, the improved focus increases efficiency and reduces the total laser energy applied. This leads to a significantly gentler and less painful treatment. This also makes it possible to dispense with anesthesia.

[0017] The two lenses generally create an adjustable optical system that allows for varying the focus of the laser beam. The lens system used for this purpose is formed, in particular, by the two (individual) lenses described here.

[0018] As an alternative to the design with two individual lenses adjustable relative to each other, a more complex optical system with multiple lenses, such as an objective lens, can also be used, particularly for the front lens. However, the preferred variant is the design with two individual lenses.

[0019] The fiber probe is designed to be hand-held by the user (doctor) during treatment and to be placed externally on a part of the body, in particular on the eye, with the contact end facing forward.

[0020] In a preferred development, a fiber end piece of an optical fiber is located in the housing, said fiber being designed to guide the light waves of the laser light. One rear lens is arranged and in particular formed at one fiber end of this optical fiber. The rear lens is therefore in particular a section of the optical fiber (the fiber end piece) itself and is therefore a monolithic component of the optical fiber. The rear lens is preferably achieved by melting / fusing the fiber end, so that the fiber material is formed at the end into a lens shape, in particular into a spherical shape. The optical fiber is in particular a glass fiber. The other, front lens is preferably formed at the exit point.

[0021] Both lenses are preferably designed as spherical lenses. They are made primarily of quartz glass. Accordingly, a glass fiber is used for the fiber end piece.

[0022] In a preferred development, a guide channel formed by a free space is formed at least between the two lenses, wherein at least one of the lenses is adjustable within this guide channel to vary the distance.

[0023] The distance between the two lenses is preferably in the range between 2 mm and 5 mm, and in particular 3.5 mm. Preferably, the distance can be varied by a (maximum) distance difference. This distance difference between the two lenses is preferably in the range of a few millimeters, and in particular in the range of less than 3.5 mm. The preferred distance between the two lenses also depends in particular on the diameter of the optical fiber. The smaller the diameter, the smaller the distance.

[0024] The optical fiber is preferably designed as a multimode fiber and therefore has a significantly larger diameter compared to a single-mode fiber.

[0025] The optical fiber preferably has a diameter of a few or several 100 pm up to, for example, 1000 pm. Typical values ​​are 200 pm, 400 pm or 600 pm. In particular, the optical fiber generally has a diameter in the range from 200 pm to 600 pm. The above-specified values ​​for the spacing apply in particular to a fiber with a diameter of 600 pm. Where reference is made here to diameter, this is understood in particular to the core diameter of a fiber core of a fiber, wherein the fiber is formed by the fiber core and a fiber cladding surrounding it. The total diameter of the fiber including the fiber cladding is typically 100 pm to 200 pm higher than the core diameter and is, for example, 300 pm for a fiber with a fiber core of 200 pm and 750 pm for a fiber with a fiber core of 600 pm.

[0026] Especially due to the multimode fiber design with a comparatively large diameter, the requirements for the entire optics are not excessively high, allowing the fiber probe and an associated light source (laser) to be constructed cost-effectively. This is especially true in conjunction with the monolithic design of the rear lens at the fiber end, particularly by melting the fiber end.

[0027] Generally, a laser is associated with the fiber probe, to which the fiber probe is connected via the optical fiber and which generates the laser light. The laser is preferably a diode laser, in which the laser light is generated simply by one, and preferably only by a single, laser diode. Alternatively, diode lasers with multiple wavelengths emitted simultaneously or sequentially are also used.

[0028] The wavelength of the laser light is in the range of, for example, 800 nm to 1000 nm. A diode laser with a wavelength of 810 nm is preferred.

[0029] The light output of the laser is typically in the range of a few watts, for example in the range of 1 W to 5 W and especially in the range of 1.5 W to 3 W.

[0030] During operation, a continuous laser beam is preferably provided. Alternatively, a pulsed laser beam with comparatively long pulses in the ms range (1 ms to 100 ms or more) can be used. In contrast to complex optical systems, which use a pulsed laser beam with very short pulses in the nanosecond range, for example, or even shorter pulse durations, such as in the femtosecond range, the required optical components can be designed comparatively simply and inexpensively.The geometric conditions, for example the distance between the lenses, the diameter and / or the curvature of the lenses are preferably selected such that - for a given wavelength of the laser light (for example 810 nm) - the light emerging from the rear lens at least largely (more than 90%, preferably more than 95% of the intensity) enters the front lens directly without reflection on the channel walls of the guide channel.

[0031] In a preferred embodiment, the front lens is fixed at the exit location, and the rear lens is arranged displaceably within the guide channel. The front lens is, in particular, attached directly to a front end surface, specifically to an opening formed by the guide channel.

[0032] In a preferred embodiment, the two lenses have different lens diameters. The rear lens has a smaller lens diameter than the front lens.

[0033] Preferably, the guide channel has a constant channel diameter over its length, at least within a longitudinal section in which the two lenses are arranged.

[0034] The diameter of the rear lens is adapted to the diameter of the guide channel in such a way that displacement is possible. A tolerance gap is specifically designed between the rear lens and the guide channel.

[0035] The front lens preferably has a diameter of greater than 0.8 mm and in particular a diameter in the range of 1 mm to 3 mm.

[0036] The posterior lens, in contrast, has a smaller diameter, for example, in the range of 0.2 mm to 1 mm. The diameter of the posterior lens is preferably a factor of 1.1 to 3 smaller than that of the anterior lens.

[0037] The front lens preferably has a diameter that is larger than the diameter of the guide channel. The front lens is therefore placed on the opening of the guide channel from the outside and rests on one edge of this opening. The diameter ratios between the lenses selected above therefore allow one lens to be displaceable within the guide channel while the other lens can be positioned at the opening of the guide channel.

[0038] The front lens is preferably the frontmost lens of the fiber probe, meaning the light for the eye being treated emerges from this front lens. The frontmost lens preferably forms the frontmost section of the fiber probe. During treatment, the frontmost lens preferably rests on the eye being treated. This means that the fiber probe is designed for direct placement of the front lens on the eye being treated. The direct placement of the front lens on the eye being treated is not prevented, for example, by obstructive housing structures or an additional attachment.

[0039] In a preferred embodiment, an opening, specifically a channel opening and in particular the previously described opening of the guide channel, is generally formed at the front end, which is sealed by the front lens. For this purpose, in particular—as previously explained—the diameter of the front lens is larger than the diameter of the opening. The front lens therefore rests sealingly on an opening edge of this opening.

[0040] This aspect of the sealed closure of such a channel opening at the front end of the fiber probe housing is considered an independent inventive concept, independent of the design with the adjustable lenses. The filing of a divisional application on this aspect, and thus on a feature combination of the preamble of claim 1 with the additional features of claim 8, remains reserved. The further preferred embodiments described here are attached to such an independent claim as preferred developments.

[0041] In a preferred embodiment, the front lens is integrally bonded to the opening, specifically to this opening edge. This is achieved, for example, using an adhesive and preferably by melting. The front end is made, in particular, of glass or quartz glass, so that, through appropriate thermal treatment, a bond can be created by fusing the front end and the front lens. This creates a reliable seal. Therefore, there is no risk of contamination from fluid penetrating the channel, especially as a result of capillary action.

[0042] In a preferred embodiment, the fiber probe as a whole has an adjustment mechanism, particularly one that can be operated by the user and, in particular, manually, by which the distance between the two lenses can be varied. With the help of the adjustment mechanism, the distance is therefore changed by mechanically shifting the lenses relative to each other.

[0043] For this purpose, the adjustment mechanism preferably has a manually operable adjustment element so that it can be operated by hand by medical personnel. The adjustment element is, for example, a sliding element, a rotary element, or even an adjustment wheel. The adjustment element is arranged in particular on a casing side of the housing of the fiber probe or is itself formed by a casing area and thus a section of the housing.

[0044] To implement the adjustment mechanism, a preferred embodiment includes an actuating element that is adjustable in a longitudinal direction and is connected to the at least one lens for its adjustment. The adjustment movement of this actuating element is initiated via the actuating element.

[0045] Preferably, the adjusting element is a housing part that is adjustable relative to another housing part. In one embodiment, the adjustment is effected, for example, by a rotational movement, in particular of the adjusting element itself, in particular such that the adjusting element is rotatably mounted on another part, for example, on the other housing part, via a thread and is thus longitudinally displaceable relative to this other part.

[0046] In a preferred embodiment, the fiber end piece is held by the adjusting element and firmly connected to it, particularly by a material bond, for example, by adhesive bonding. The connection is spaced apart from the rear lens. The rear lens is therefore adjusted indirectly via the adjustment of the fiber end piece. This is a simple design.

[0047] The fiber end piece, in particular, has a rear section, which is held by the control element and, in particular, rests therein. The control element, in particular, has a channel, which is, in particular, a section or an extension of the aforementioned guide channel through which the fiber end piece is guided. The rear section of the fiber end piece rests in this channel, for example, precisely and, in particular, frictionally or materially, and is thus secured in the control element.

[0048] The rear section is preferably surrounded by a sheath, for example a protective tube, which is fastened in the adjusting element with sufficient holding force - for example by frictional engagement or material bond - so that when the adjusting element is adjusted, the fiber end piece and with it the rear lens are displaced in the longitudinal direction relative to the front lens.

[0049] In a useful embodiment, the housing has a rear housing part which is designed in particular as a hand part, which is therefore designed to be held by the doctor's hand during operation.

[0050] Furthermore, the housing has a front housing part, which is preferably reversibly detachably connected to the rear housing part. This front housing part therefore represents a replaceable tip or a replaceable attachment.

[0051] The housing preferably consists of these two housing parts, i.e. the handpiece and the interchangeable attachment.

[0052] The previously described guide channel extends from the rear housing part into the front housing part and runs to the exit point. The guide channel is designed, in particular, as a continuous guide channel that extends from a rear, proximal opening of the housing to the front distal opening at the front end, where the guide channel is sealed, in particular by the front lens.

[0053] The rear housing part preferably has a continuous channel, which is a section or an extension of the guide channel through which the fiber end piece can be pushed.

[0054] In a suitable embodiment, the front housing part consists of a transparent material and in particular of glass or quartz glass or alternatively of a polymer.

[0055] As an alternative to the transparent design, a non-transparent design for the front housing part is used. In this case, it is made of metal or ceramic, for example.

[0056] According to an optional embodiment, a coating is also applied in the area of ​​the guide channel to reflect laser light from the channel walls. Such reflective coatings are useful, for example, in lenses to reduce Fresnel reflections and thus increase transmission.

[0057] The rear housing part, on the other hand, preferably consists of a non-transparent material, for example of plastic, but preferably of metal, for example of aluminum, in particular a colored and, for example, black, blue or red anodized aluminum.

[0058] The fiber probe is, in particular, a preconfigured disposable or reusable component to which the fiber optic cable is already connected. The fiber optic cable has, for example, a connector, in particular a plug connector, at its proximal end for connecting, in particular for plugging in, an optical component. The optical component is, for example, a laser, or another fiber optic cable, essentially an extension for connecting to a laser.

[0059] The fiber probe described here enables a cost-effective fiber probe with an adjustable, comparatively wide focus while maintaining a simple and cost-effective design.

[0060] Preferably, a set of several differently designed fiber probes is provided, wherein these differ with regard to the diameter of the anterior lens, and in particular only with regard to the diameter of the anterior lens. Due to the different diameters, with otherwise identical construction, different focal lengths are provided, so that a broad range of applications is covered across the multiple fiber probes, even for different anatomies, e.g., in children and adults.

[0061] An embodiment of the invention is explained in more detail below with reference to the figures, which show, in simplified representations:

[0062] FIG 1 shows a partial side view in the manner of a sectional view of a fiber probe,

[0063] FIGS 2A, 2B are schematic diagrams to explain the variable adjustment of the focus of a laser beam by varying the distance between two spaced-apart lenses, and FIGS 3A-3B are highly simplified representations of a fiber probe with a further optical attachment element in different variants.

[0064] A manually operable fiber probe 2 shown in Figure 1 is used for the therapeutic treatment of medical tissue, and in particular for glaucoma treatment, using laser light. The laser light has a wavelength of 810 nm, for example. The laser light is provided by a laser (not shown here), in particular a diode laser, and is coupled into an optical fiber 4 (optical waveguide fiber), which is part of an optical waveguide cable 6. The optical waveguide cable 6 has, in particular, a sheath 8, which is designed, for example, as a tube, in which the optical fiber 4 is guided.

[0065] The optical fiber used is a multimode fiber with a diameter (core diameter) in the range between 200 pm and 600 pm. The fiber preferably has a numerical aperture in the range of 0.2 to 0.5.

[0066] The fiber probe 2 is a preconfigured component in which the fiber optic cable 6 is already part of the fiber probe 2. Therefore, it only needs to be connected to a laser via the rear end of the fiber optic cable 6.

[0067] The fiber probe 2 has a two-part housing 10 in the exemplary embodiment, with a rear housing part forming a handle 10A. A front housing part is attached to this handle 10A, for example, via a screw connection and generally preferably in a reversibly replaceable manner. This front housing part is therefore an attachment 10B. The housing 10 extends in a longitudinal direction L from the handle 10A to the attachment 10B.

[0068] The two housing parts 10A, 10B form an internal, continuous channel, referred to as a guide channel 12. In the exemplary embodiment, this channel has a constant diameter D1. A fiber end piece 14 of the optical fiber 4 extends into this guide channel 12, which is divided within the housing 10 into a rear section 14A and a front section 14B. In the rear section 10A, the fiber 4 is still surrounded by the cladding 8, whereas it is exposed in the front section 14B.

[0069] At the front fiber end of the fiber end piece 14, viewed in the longitudinal direction L, a particularly spherical rear lens 16A is formed on the end of the fiber 4. This is formed, in particular, by melting the fiber 4. The rear lens 16A has a lens diameter D2.

[0070] The housing 10, in particular the attachment 10B, has a front end 18 (distal contact end) viewed in the longitudinal direction L. The front surface formed there is typically adapted to the curvature of the human eye and is particularly designed as a concavely curved front surface, which is also oriented obliquely to the longitudinal direction L.

[0071] The guide channel 12 opens at this front end 18 at an opening closed by a front lens 16B. The front lens 16B also defines an exit point for the laser light. Preferably, both the attachment 10B and the front lens 16B are made of glass, and the front lens 16B is integrally bonded to the attachment 10B by melting. The front lens 16B thus reliably seals the opening and thus the guide channel 12 and prevents the penetration of dirt particles or liquid, which could lead to contamination and thus, in particular, to an impairment of the propagation of the laser light during operation.

[0072] The two lenses 16A, 16B are adjustable relative to each other in the longitudinal direction L, so that a distance A between the two lenses 16A, 16B can be varied. By varying the distance, the focus of the laser light can be changed during operation.

[0073] The front lens 16B is fixed relative to the housing 10, and the rear lens 16A is displaceably arranged within at least a portion of the guide channel 12. Specifically, the rear lens 16A, together with the fiber end piece 14, is displaceable relative to the front lens 16B.

[0074] To vary the distance A, the fiber probe 2 has an adjustment mechanism 20, which is only illustrated in a highly simplified manner in the figures. This adjustment mechanism has a manually operable adjustment element 22, which can be manually operated by the operator. The adjustment element 22 causes the relative adjustment of the two lenses 16A, 16B to each other.

[0075] The adjustment element 22 is arranged, in particular, on the outside of the housing, i.e., on the casing, or is formed by the casing itself. For example, it is an adjustment wheel that can be operated with the fingers by rotating it.

[0076] The adjustment mechanism 20 further comprises an adjusting part 24, which in the exemplary embodiment is formed in particular by the handle 10A and thus by a housing part. The adjusting part 24 is generally connected to the displaceable rear lens 16A. Specifically, it is suitably fastened to the jacket 8 of the fiber end piece 14, for example by frictional engagement and in particular by material bonding, for example by gluing, so that an adjusting movement of the adjusting part 24 in or against the longitudinal direction L displaces the entire fiber end piece 14.

[0077] In the preferred embodiment, in which the actuating part 24 is designed as a housing part, the two housing parts 10A, 10B are displaceable relative to one another in the longitudinal direction L.

[0078] The adjustment of the adjusting part 24 is effected by the adjusting element 22, which, for example, via a worm gear, converts a rotary movement into a longitudinal movement of the adjusting element 22. In principle, other mechanical actuation devices are also possible. For example, a separate adjusting part 24 can be arranged inside the housing 10, which engages the fiber end piece 14, particularly in the rear section 14A. The adjusting part 24 is designed, for example, in the manner of a slider, which lies in a partial section of the guide channel 16.

[0079] Especially in a variant in which the housing parts 10A, 10B are offset relative to one another in the longitudinal direction L, the adjusting element 22 is formed, for example, by a casing area or a grip recess on the handle 10A and the two housing parts 10A, 10B are connected to one another via a thread, so that the desired change in distance is achieved by rotating the two housing parts 10A, 10B relative to one another.

[0080] The two housing parts are, for example, two sections of the handset 10A, which are connected to each other via a thread.

[0081] The mode of operation is explained using FIGS. 2A and 2B: In the two figures, two housing parts 10A, 10B are sketched as examples, which have a distance between them that can be varied in the longitudinal direction L. This changes the distance A between the two lenses 16A, 16B.

[0082] In the exemplary embodiment, both lenses 16A, 16B are convexly curved. Due to their convex shape and, in particular, lens shape or spherical shape, they are therefore designed as converging lenses. Possible beam paths of the laser light as a function of the distance A are shown in the two figures. In the situation according to Figure 2A, a particularly maximum distance A is set, at which a focal point 26 of the laser beam generated by the two lenses is positioned as close as possible in front of the front lens 16B. As the distance A becomes increasingly smaller, the laser beam widens, or the focal point 26 shifts forward in the longitudinal direction L.

[0083] As an alternative to the illustrated embodiment, in which the front lens 16B is a simple lens, the front lens 16B can also be designed as a complex lens system and / or as an objective. This can then also include concave lens surfaces. However, the preferred variant is the design shown in FIG. 1, FIG. 2A, and FIG. 2B, with two simple individual lenses.

[0084] Finally, it is also possible to arrange an additional optical system 28 as part of an attachment element 30 or directly as the attachment element 30 itself on the housing 10, as shown in FIGS. 3A to 3B. This additional optical system 28 is therefore generally arranged downstream of the two lenses 16A, 16B, which are adjustable relative to one another, in the beam direction. In alternative, preferred variants, however, additional optical systems 28 and / or attachment elements 30 are omitted.

[0085] In FIGS. 3A to 3B, the housing 10 is shown in a highly simplified manner, without explicitly showing the two housing parts 10A, 10B and the adjustment mechanism 20 for the relative adjustment of the two lenses 16A, 16B. The attachment element 30 is, in particular, fixedly mounted relative to the front housing part 10B. For example, it is attached to this front housing part 10B. Alternatively, it can also be fixed relative to the rear housing part 10A.

[0086] For this purpose, the additional attachment element 30 has a sleeve-shaped section, for example, with which it is attached to the housing 10. In particular, the attachment element 30 is slipped onto the housing 10 and is suitably fixed and held there. The attachment element 30 is preferably reversibly interchangeable, so that the fiber probe 2 can be used without or with different attachment elements 30 as needed.

[0087] Depending on the application and requirements, the attachment element 30 is designed differently. According to FIG. 3A, a separate element is mounted in or on the attachment element 30 as the optics 28, which is designed, for example, as an objective with multiple lenses. The optics 28 generally serves for further beam shaping, e.g., focusing or expanding the laser beam. According to FIG. 3B and FIG. 3C, the attachment element 30 itself forms an optics

[0088] 28. In this case, the attachment element 30 as such forms a light-conducting element.

[0089] This is designed like a prism, as shown in FIG 3B. It serves primarily to deflect the beam.

[0090] According to FIG. 3C, the attachment element 30—particularly in addition to a prismatic design for deflection analogous to FIG. 3B—forms a lens itself, which serves for further beam shaping. In the exemplary embodiment, a convexly curved lens for beam focusing is shown.

[0091] Preferably, however, such an (additional) optic 28 is omitted, and focusing is performed exclusively via the two lenses 16A, 16B. The attachment element 30 also preferably does not have an optic 28 and is not designed as a lens. In particular, the attachment element 30 is omitted.

[0092] Overall, the adjustment mechanism 20 achieves a special structure of the fiber probe 2 with the adjustable optics formed by the two lenses 16A, 16B, which enables the operator to easily change the focus of the laser beam manually.

[0093] The fiber probe 2 is generally used for treating medical (human / animal) tissue using laser irradiation, for example, on the skin's surface. Due to its variable focus, the fiber probe 2 is specifically designed for treating the eye, particularly in glaucoma treatment, where the laser beam is used to treat tissue inside the eye.

[0094] Special advantages of the fiber probe 2 described here are:

[0095] - manually adjustable, variable focus of the laser beam,

[0096] - reliable sealing of the interior of the fiber probe 2 by the front lens 16B, - thus option of multiple use,

[0097] - due to the focusability, less laser energy is required, thus more gentle and painless treatment,

[0098] - this means that anesthesia is not necessary.

[0099] List of reference symbols

[0100] 2 fiber probes

[0101] 4 optical fibers

[0102] 6 fiber optic cables

[0103] 8 coat

[0104] 10 Housing 10 A, Handpiece 10B Attachment

[0105] 12 guide channel

[0106] 14 Fiber end piece

[0107] 14A rear section 14B front section 16A rear lens 16B front lens

[0108] 18 front end

[0109] 20 adjustment mechanism

[0110] 22 Adjustment element

[0111] 24 control element

[0112] 26 Focus point 28 Additional optics 30 Attachment element

[0113] A distance

[0114] D1 Diameter guide channel

[0115] D2 diameter of the rear lens

[0116] D3 diameter front lens

Claims

Claims 1. Hand-held fiber probe (2) for laser treatment of medical tissue, in particular for glaucoma treatment, which has an optical fiber cable (8) at least in the assembled state, with a housing (10) which has a front end (18) with an exit point for laser light, characterized in that a front and a rear lens (16A, 16B) are arranged, which can be adjusted relative to one another by the user, so that the laser beam can be varied by varying a distance (A) between the two lenses (16A, 16B).

2. Fiber probe (2) according to the preceding claim, characterized in that a fiber end piece (14) of an optical fiber (4) is arranged in the housing (10), on which the one rear lens (16A) is arranged.

3. Fiber probe (2) according to the preceding claim, wherein the rear lens (16A) is a monolithic portion of the fiber end piece (14) and is formed in particular by melting the fiber end piece (14).

4. Fiber probe (2) according to one of the preceding claims, characterized in that a guide channel (12) is formed between the lenses (16A, 16B) and at least one of the lenses (16A) is adjustable within the guide channel (12) to vary the distance (A).

5. Fiber probe (2) according to one of the preceding claims, characterized in that a distance between the lenses (16A, 16B) is in the range between 2 mm and 5 mm.

6. Fiber probe (2) according to one of the preceding claims and according to claim 2, characterized in that the fiber (4) and in particular the fiber end piece (14) is designed as a multimode fiber and / or has a diameter in the range of at least 100 pm to, for example, 1000 pm and in particular in the range between 200 pm and 600 pm.

7. Fiber probe (2) according to one of the preceding claims, characterized in that the front lens (16B) is arranged stationary at the exit location and the rear lens (16A) is arranged displaceably within the guide channel (12).

8. Fiber probe (2) according to one of the preceding claims, characterized in that the two lenses (16A, 16B) have different lens diameters (D1, D2).

9. Fiber probe (2) according to one of the preceding claims, characterized in that the front lens (16B) has a diameter (D2) of greater than 0.8 mm and in particular a diameter (D2) in the range of 1 mm to 3 mm.

10. Fiber probe (2) according to the preceding claim, characterized in that the rear lens (16A) has a diameter which is smaller by a factor of 1.1 to 3 than the front lens.

11. Fiber probe (2) according to one of the preceding claims, characterized in that an opening is formed at the front end (18) which is sealed by the front lens (16B), wherein the front lens (16B) is attached to the opening in particular by a material fit.

12. Fiber probe (2) according to one of the preceding claims, characterized in that the two lenses (16A, 16B) are the only lenses (16A, 16B) and that the front lens (16B) is designed in particular for direct placement on an eye to be treated.

13. Fiber probe (2) according to one of the preceding claims, characterized in that it has an adjustment mechanism (20) by means of which the distance (A) between the two lenses can be varied.

14. Fiber probe (2) according to the preceding claim, characterized in that the adjustment mechanism (20) is manually operable and has an adjustment element (22) which is arranged in particular on the housing (10) or is formed by a section of the housing (10).

15. Fiber probe (2) according to one of the two preceding claims, characterized in that the adjustment mechanism (20) has an adjusting part (24), in particular a housing part (10A), which is adjustable in a longitudinal direction (L) and which is connected to the at least one lens (16A) for adjusting the latter.

16. Fiber probe (2) according to the preceding claim, characterized in that the fiber end piece (14) is held by the actuating part (24, 16A) and in particular is integrally connected thereto.

17. Fiber probe (2) according to the preceding claim, characterized in that the fiber end piece (14) has a rear section (14A) with a jacket (8) and that the rear section (14A) is fastened to the actuating part (24), in particular by means of a material fit.

18. Fiber probe (2) according to one of the two preceding claims, characterized in that the housing (10) has a rear housing part designed as a hand part (10A) and a front housing part with the front end (18), wherein the front housing part is fastened as an attachment (10B) to the hand part (10A) in a preferably reversibly detachable manner and is preferably made of a transparent material, especially glass.

19. Fiber probe (2) according to one of the preceding claims, characterized in that a further optic (28) is attached to the housing (10) in the region of the front end (18), in particular as an attachment element (30) or as part of an attachment element (30).

20. Fiber probe (2) according to one of the preceding claims, characterized in that it is connected to a laser for generating the laser light, wherein the laser is designed as a diode laser.

21. A set of several fiber probes (2), each designed according to one of the preceding claims, wherein the fiber probes differ with respect to the diameter of the front lens (16B).

Images