Method and device for destroying or removing stones, concretions and other hard substances in the body

Abstract

The present invention relates to a device (1) for destroying and removing solid bodies (6), such as concretions, in the human or animal body, comprising: a laser (2) for generating a light emission; an optical waveguide (3) for guiding the light emission from the laser (2) to a treatment location (7), wherein a proximal end of the optical waveguide (3) is coupled to the laser (2) and a distal end of the optical waveguide (3) can be introduced into the human or animal body, wherein the light emission can exit at the distal end (32) of the optical waveguide (3); and a liquid supply device (4) for supplying a liquid medium to the treatment location (7).

Description

[0001] Applicant: biolitec Holding GmbH & Co KG

[0002] Our reference: BRG31223PCT

[0003] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0004] Date: November 5, 2025

[0005] METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0006] Technical field

[0007] The present invention relates to a device for destroying and removing solids, such as concretions, in the human or animal body.

[0008] State of the art

[0009] Solid bodies in the human or animal body, such as stones, are the result of the concretion of material, primarily mineral salts, that forms in an organ or duct. They can cause irritation of the surrounding tissue, pain, swelling, and inflammation. By obstructing an opening or duct, they can disrupt the normal flow of fluids and impair the function of the affected organ. This can also lead to infection of these organs. The most common types are kidney stones, which occur in the urinary tract, especially in the kidneys or bladder, and gallstones, which can form in the gallbladder.

[0010] In medicine, there are several approaches to treating such solids. Stones in the upper urinary tract can be treated with extracorporeal shock wave lithotripsy (ESWL). This type of lithotripsy works best for small-diameter stones. Another option is endoscopic therapy. Endoscopic lithotripsy relies on visualizing the stone and simultaneously applying a form of energy to break it into either extractable or passable fragments. Energy sources used in endoscopic lithotripters include ultrasound, electrohydraulic, and mechanical devices, as well as various lasers.

[0011] Laser lithotripsy was first commercially introduced in the late 1980s. It is based on the fact that pulsed light energy, delivered via an optical fiber, is converted into mechanical energy in the form of a cavitation bubble, which is associated with the generation of shock waves. This mechanical energy is used for the destruction of

[0012] Page 1 of 17 Applicant: biolitec Holding GmbH & Co KG

[0013] Our reference: BRG31223PCT

[0014] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0015] Date: November 5, 2025

[0016] This process is responsible for the formation of concretions. It is aided by plasma formation on the surface of the stones to be crushed. High-power laser pulses are transmitted to the stone surface via very thin optical fibers. When the stones or the surrounding fluid absorb the radiation and the power density exceeds a certain threshold, plasma formation occurs. The plasma, generated by ionization and rapid growth of matter, produces spark bubbles associated with cavitation and shock wave effects. The plasma and cavitation phenomena are accompanied by strong photo- and thermoablative effects; the plasma bubbles have internal temperatures of several thousand degrees, and the presence of cavitation effects is associated with a characteristic noise generated by the shock waves.

[0017] Various lasers are used for this purpose, such as pulsed dye lasers, alexandrite lasers, Nd:YAG lasers, or holmium:YAG lasers (see non-patent literature: P. Kronenberg, et al., Advances in Lasers for the Treatment of Stones - a Systematic Review, Curr. Urol. Rep. 19, 45, 2018). Additionally, diode lasers are used, for example, as pump lasers. Such diode lasers generally offer numerous advantages over ion-crystal lasers. Among other things, diode lasers exhibit higher power output with smaller dimensions and weight and generally require simpler and smaller air cooling systems. However, most known diode lasers do not achieve the required peak power.

[0018] More recently, the thulium fiber laser has been introduced (see non-patent literature: P. Kronenberg, et al., The laser of the future: reality and expectations about the new thulium fiber laser—a systematic review, Transl. Androl. Urol. 8 (Suppl 4), pp. 398–17, 2019), which is also used in lithotripsy. The thulium fiber laser (TFL) uses a long, thin quartz fiber doped with thulium as the active laser medium. Several diode lasers pump energy through the fiber and excite the thulium ions. The photons are emitted at a wavelength of 1940 nm and directed into the surgical field via an outgoing laser fiber. Although, for example, the holmium:YAG laser lithotripter can operate with high pulse energies, efficient operation during lithotripsy is limited to low pulse rates (~10 Hz). Conversely, the thulium fiber laser is limited to low pulse energies, but operates efficiently at high pulse rates (see non-patent literature: O. Traxer, et al.)., Thulium fiber laser: the new player for kidney stone treatment? A comparison with Holmium:YAG laser, World J. Urol. 38, pp. 1883-1894, 2020; and cf. non-patent literature: RL Blackmon, at al., Comparison of holmium:YAG and thulium fiber laser lithotripsy: ablation thresholds, ablation rates, and retropulsion effects. J. Biomed. Opt. 16, 071403, 2011). The.

[0019] Page 2 of 17 Applicant: biolitec Holding GmbH & Co KG

[0020] Our reference: BRG31223PCT

[0021] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0022] Date: November 5, 2025

[0023] The thulium fiber laser therefore represents a significant advancement in lithotripsy. However, the other important factor for successful and patient-benefit-oriented clinical application is the laser fiber used for treatment, its radiation properties, and the actual effectiveness of stone fragmentation.

[0024] To deliver sufficient pulse energies, high diode pumping powers are required. Current systems can be equipped with 50 pm core fibers, which should enable improved flexibility and more efficient material removal.

[0025] Despite the progress made, current state-of-the-art devices and systems are unable to combine high pulse energies with sufficient beam quality and high pulse frequency. This results in long treatment times and significant heating of the stones.

[0026] Due to these disadvantages and shortcomings of the described state of the art, there is a need for a device that offers a faster, safer and more economical alternative.

[0027] Description of the invention

[0028] Starting from the known state of the art, it is an object of the present invention to provide an improved device for the destruction and removal of solids in a human or animal body, such as kidney stones in the urinary tract or tartar.

[0029] The task is accomplished by a device for the destruction and removal of solid bodies such as concretions in the human or animal body, with the characteristics of

[0030] Claim 1 is solved. Advantageous further developments result from the dependent claims, the description and the figures.

[0031] Accordingly, a device for the destruction and removal of solids, such as concretions, in the human or animal body is provided. According to the invention, the device comprises a laser for generating light emission, an optical waveguide for directing the light emission from the laser to a treatment site, wherein a proximal end of the optical waveguide is coupled to the laser and a distal end of the optical waveguide can be inserted into the human or animal body, with the light emission occurring at the distal end.

[0032] Page 3 of 17 Applicant: biolitec Holding GmbH & Co KG

[0033] Our reference: BRG31223PCT

[0034] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0035] Date: November 5, 2025, of the optical fiber, and a liquid supply device for supplying a liquid medium to the treatment site, wherein the laser comprises at least one laser fiber designed as a tapered laser fiber. This makes it possible to ablate small fragments of a solid, such as calculus or tartar, by means of water absorption. During the treatment of the solid, the laser's light emission is guided through the liquid, such as water, supplied by the liquid supply device, thereby forming a vapor channel. The spatial limitation of the vapor channel depends on the irradiation and, in particular, the irradiation path. The ablation effect can also be influenced by the distance between the distal end of the optical fiber and the solid, for example, by utilizing retropulsion and / or suction effects.

[0036] The term "solids" here refers to concretions such as gallstones, urinary stones, kidney stones, vaginal stones and salivary stones, as well as tartar.

[0037] In a further preferred embodiment of the described device, the laser comprises at least one laser fiber, wherein the laser fiber comprises a tapered quartz fiber doped with thulium and / or holmium.

[0038] The beam quality can be improved by using tapered, thulium- and / or holmium-doped quartz fibers, so-called doped fiber amplifiers. This increases the energy density of the laser beam and, accordingly, optimizes the properties of the laser light for treatment.

[0039] A laser using a thulium- or holmium-doped quartz fiber as the active laser medium is called a holmium fiber laser or thulium fiber laser (TFL). The quartz fiber used is typically relatively long and thin. Energy is pumped through the thulium- and / or holmium-doped quartz fiber by means of several diode lasers, thereby exciting the thulium or holmium ions. The photons are emitted by the thulium laser at a wavelength of 1940 nm or by the holmium laser at a wavelength of 2120 nm and guided to the treatment site via the optical fiber.

[0040] A laser with a thulium-doped quartz fiber is limited to low pulse energies and operates efficiently at high pulse rates. Higher pulse rates optimize the pulverization of the solid, resulting in a higher dust volume and a smaller...

[0041] Page 4 of 17 Applicant: biolitec Holding GmbH & Co KG

[0042] Our reference: BRG31223PCT

[0043] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0044] Date: November 5, 2025

[0045] The particle volume is increased. The use of a tapered, thulium-doped quartz fiber can significantly optimize the efficiency of the laser system and, consequently, the treatment, due to its amplifying properties.

[0046] In another preferred embodiment, the thulium laser emits light at a wavelength in the range of 1920 nm to 1960 nm, preferably 1940 nm.

[0047] In another preferred embodiment, the holmium laser emits light at a wavelength in the range of 2100 nm to 2150 nm, preferably 2120 nm.

[0048] In a further preferred embodiment, the optical waveguide comprises one optical fiber or a plurality of optical fibers. An optical waveguide in the form of a plurality of optical fibers can be configured as a multi-fiber or fiber bundle.

[0049] In a further preferred embodiment of the described device, the liquid supply device can comprise a tubular line that is integrated into or arranged on the optical waveguide and runs at least partially parallel to the optical waveguide.

[0050] In the case of a multi-fiber optical waveguide, several fibers can be arranged in a circular configuration around the liquid delivery unit. The circularly arranged fibers supply the laser light required for fragmenting solids, while the central liquid delivery unit provides a liquid environment around the solid and facilitates rinsing. In the case of a single-fiber optical waveguide, the optical waveguide and liquid delivery units can be arranged side-by-side or concentrically. In the latter case, the optical waveguide runs inside the liquid delivery unit, which saves space and simplifies handling of the device, particularly its insertion into a human or animal body.

[0051] In another preferred embodiment of the device, a lens is arranged at the distal end of the optical waveguide to provide a defined beam angle of light emission from the distal end of the optical waveguide.

[0052] This allows for an improvement in the directional characteristics of the light emission from the optical waveguide and the laser. In particular, predefined directional properties of the light emission, such as focusing or collimation, can be achieved through the use of this method.

[0053] Page 5 of 17 Applicant: biolitec Holding GmbH & Co KG

[0054] Our reference: BRG31223PCT

[0055] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0056] Date: November 5, 2025. Appropriate lenses will be provided. The selection of a specific beam angle, adapted to the geometry of the treatment area, enables effective destruction / ablation of solids.

[0057] The term lens encompasses both transparent disks, at least one of whose two surfaces is curved, for example spherically, and transparent disks or rods with flat surfaces, such as gradient lenses.

[0058] In another preferred embodiment of the described device, the lens is a gradient lens, which is spliced ​​to the distal end of the optical waveguide. Gradient lenses, also called gradient-index lenses (GRIN lenses), allow the optical properties of continuous material transitions to be utilized. Gradient lenses are cylindrical, transparent optical components with a refractive index that decreases in the radial direction. Typically, the refractive index decreases quadratically with distance from the center. A short rod made of this material functions like an ordinary converging lens, but has flat surfaces at the light-entry and light-emission faces. This design simplifies assembly, miniaturization, and integration with other optical elements. The flat surface of these lenses offers a particular advantage over conventional lenses when coupled to the optical waveguide.

[0059] Splicing the gradient lens to the distal end of the optical fiber allows for precise positioning of the optical fiber relative to the gradient lens. The light-guiding cores of the optical fiber and the gradient lens can be precisely aligned. Particularly low attenuation values ​​of approximately 0.03 dB can be achieved at the transition between the optical fiber and the gradient lens.

[0060] In another preferred embodiment, the lens is a mini-diamond lens. Diamond lenses enable a compact design characterized by comparatively thin optics and relatively low weight. Low weight at the distal end of the optical waveguide is advantageous and facilitates handling, for example, when inserting the device into a human or animal body. As a result, mini-diamond lenses can help to simplify processing even in hard-to-reach areas. Furthermore, diamond lenses exhibit a comparatively high refractive index and a comparatively high thermal conductivity.

[0061] Page 6 of 17 Applicant: biolitec Holding GmbH & Co KG

[0062] Our reference: BRG31223PCT

[0063] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0064] Date: November 5, 2025

[0065] In another preferred embodiment, the lens comprises titanium-doped quartz glass. This makes the lens or the end piece of the optical waveguide more resistant, for example to temperature stress.

[0066] In a further preferred embodiment, the laser fiber, preferably the active fiber core of the laser fiber, can have a numerical aperture (NA) between 0.02 and 0.25, preferably between 0.06 and 0.22, particularly preferably between 0.06 and 0.14, and particularly preferably 0.1.

[0067] A low numerical aperture (NA) (for example, NA < 0.15) enables the comparatively effective destruction of concretions or stones. A low NA is particularly important for small fiber core diameters, as these cases experience a significant drop in power density due to unfavorable parameters. Specifically, a higher NA is associated with greater propagation losses of the laser light. With a lower NA, more intense laser radiation is obtained at the fiber exit point, making it easier to destroy stones with light of a low NA.

[0068] In another preferred embodiment, the laser can include tapered amplifier fibers to improve beam quality. This increases the energy density of the laser beam and thus optimizes the properties of the laser light for treatment. Furthermore, the use of tapered amplifier fibers allows for fibers with a particularly low NA (down to 0.06 or even lower). The tapered amplifier fibers can, for example, be conical amplifier fibers.

[0069] In a further preferred embodiment, the laser emits light at a wavelength in the range of 1700 nm to 2150 nm, preferably 1920 nm to 1960 nm, and particularly preferably 1940 nm. It has been shown that wavelengths from the aforementioned ranges have an advantageous effect on the destruction of concretions or stones.

[0070] In a further preferred embodiment of the described device, the light emission of the laser can be pulsed, preferably with a pulse duration between 1 and 999 picoseconds.

[0071] In a further preferred embodiment of the present invention, the pump diodes are operated in pulsed mode (or quasi-CW pulse mode); this allows higher output pulses of the diodes (compared to CW operation) and consequently of the conical amplifier.

[0072] Page 7 of 17 Applicant: biolitec Holding GmbH & Co KG

[0073] Our reference: BRG31223PCT

[0074] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0075] Date: November 5, 2025, at the same cost. Additionally, air cooling will be possible, as average power consumption and cooling requirements can be kept low.

[0076] In a further preferred embodiment of the described device, double-clad, tapered fibers are used as the amplification medium to prevent damage to the device from back reflection of the laser beam. Back reflections, which pose a problem in conventional fiber laser designs, are far less problematic with tapered amplifiers, since the backward-directed radiation can be diverted via the cladding in the conical zone.

[0077] In further preferred embodiments, the generated output pulses from the conical amplifier are introduced into the treatment fibers at very low NA; simultaneously, short fibers of approximately 2 to 3 meters in length are used. To prevent excessive bending during treatment, a suitable bend protection is placed around a portion of the treatment fiber in further preferred embodiments. In addition to low NAs, these devices allow power densities to be achieved during the pulses at the stone that are comparable to those of holmium sources and even surpass them with respect to the fracturing effects.This is further facilitated by the higher light absorption of water at the (emitted) wavelength of the thulium laser, while the passage through the water in front of the stone is made easier by the good beam quality and the lower divergence and smaller diameter of the beam compared to previous holmium lasers and previously used fiber systems.

[0078] These embodiments can improve the effective destruction of concretions or stones. The laser can provide pulses in various ways, for example, by generating laser pulses as pulse packets. The laser includes a main oscillator that generates a continuous sequence of short pulses with a duration At (from less than one picosecond to several hundred picoseconds) and a repetition rate f (from a few kHz (kilohertz) to several hundred MHz (megahertz)). The signal from the main oscillator is extracted by the amplifier and then fed to an intensity modulator, which forms a pulse packet with a duration x [Tau] and a period T from a continuous sequence of pulses. The duration of a pulse packet (burst envelope duration) can vary from one nanosecond to several thousand milliseconds, particularly preferably up to 1000 ms.

[0079] Page 8 of 17 Applicant: biolitec Holding GmbH & Co KG

[0080] Our reference: BRG31223PCT

[0081] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0082] Date: November 5, 2025

[0083] In a further preferred embodiment, the pulsed light emission of the laser can have a repetition frequency between 1 kHz and 500 MHz, preferably between 1 and 200 MHz. A repetition frequency or repetition rate of the pulse packets between 1 kHz and 500 MHz enables comparatively faster ablation of concretions or stones. The peak power of the pulse packets in the burst can be up to 3 MW, preferably up to 500 kW. High peak powers of up to 3 MW, preferably up to 500 kW, are provided to increase the ablation efficiency.

[0084] In another preferred embodiment of the described device, the light emission of the laser can be constant.

[0085] Brief description of the characters

[0086] Preferred further embodiments of the invention are explained in more detail by the following description of the figures. These show:

[0087] Figure 1 schematically shows the construction of a device for destroying and removing solids;

[0088] Figure 2a schematically shows the distal end of an optical waveguide;

[0089] Figure 2b schematically shows the distal end of an optical waveguide;

[0090] Figure 3a schematically shows the distal end of an optical waveguide with a gradient lens;

[0091] Figure 3b schematically shows the distal end of an optical waveguide with a lens;

[0092] Figure 4a schematically shows the distal end of an optical waveguide with a focusing lens.

[0093] Gradient lens;

[0094] Figure 4b schematically shows the distal end of an optical waveguide with a collimating gradient lens;

[0095] Figure 5a schematically shows a sectional view of an optical waveguide with a concentric liquid supply device;

[0096] Page 9 of 17 Applicant: biolitec Holding GmbH & Co KG

[0097] Our reference: BRG31223PCT

[0098] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0099] Date: November 5, 2025

[0100] Figure 5b schematically shows a sectional view of an optical waveguide with circumferential

[0101] Liquid supply device;

[0102] Figure 6 schematically visualizes the shape of a pulse packet; and

[0103] Figure 7 schematically shows the modular structure of a fiber laser.

[0104] Detailed description of preferred implementation examples

[0105] Preferred embodiments are described below with reference to the figures. Identical, similar, or equivalent elements in the different figures are designated with identical reference numerals, and repeated descriptions of these elements are sometimes omitted to avoid redundancy.

[0106] Figure 1 schematically shows the basic structure of a device 1 for the destruction and removal of solids. The device 1 shown in Figure 1 serves for the safe and efficient destruction / removal of solids such as concretions, stones, or other hard substances in the body. The device 1 comprises a laser 2 with a tapered, thulium- and / or holmium-doped quartz fiber, also known as a doped fiber amplifier (laser source), which emits at least one wavelength. Various pulsed dye lasers, multimode fiber lasers, or diode lasers can be used as the laser 2 in combination with the tapered, thulium- and / or holmium-doped amplifier (tapered, thulium- and / or holmium-doped fiber amplifier). Diode lasers can also be used, which in turn pump a multimode fiber laser that is then combined with the tapered, doped fiber amplifier.Furthermore, the device may include an additional seed laser that delivers the laser pulses. The device also includes an optical waveguide coupling unit 22, an optical waveguide 3 comprising one or more optical fibers that guide the laser radiation to the treatment site 7, with the laser radiation exiting the optical waveguide 3 at a distal end 32, and a liquid delivery device 4 used to create a liquid environment around a solid 6. The laser 2 emits at least one wavelength that is strongly absorbed in the delivered liquid to provide ablation and cavitation effects that lead to the destruction of the solid 6. The device may also include an undoped treatment fiber.

[0107] Page 10 of 17 Applicant: biolitec Holding GmbH & Co KG

[0108] Our reference: BRG31223PCT

[0109] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0110] Date: November 5, 2025

[0111] The at least one fiber of the optical waveguide 3 has a nadir in the range of 0.02 to 0.4. To further improve the destructive ablation effect on the solid 6, the laser 2 has a peak power of up to 3 MW and short laser pulses (duration μ from a few picoseconds to several hundred picoseconds).

[0112] The laser 2 emits light at a wavelength between 1700 and 2150 nm. In a preferred embodiment, the laser emits at a wavelength in the range of 1920 to 1960 nm, particularly preferably at 1940 nm.

[0113] Figure 2a schematically shows the distal end 32 of an optical waveguide 3 comprising a fiber 30, which has a high NA (e.g., >0.25) and is directed towards a solid 6. The fiber 30 encloses a sheath 33. The laser light emerges from the distal end 32 of the optical waveguide 3 with a relatively large acceptance angle or collimation angle 0 and forms an exit cone 34.

[0114] Figure 2b schematically shows the distal end 32 of an optical waveguide 3 comprising a fiber 30, which has a low NA (e.g., <0.25). The laser light emerges from the distal end 32 of the optical waveguide 3 with a relatively small acceptance angle or collimation angle 0. In total, compared to the embodiment shown in Figure 2a, this results in a smaller exit cone 34 of the laser light, leading to improved destruction or...

[0115] The ablation characteristics of a solid to be treated lead to this.

[0116] Figure 3a schematically shows the distal end 32 of an optical waveguide 3 comprising a gradient lens 52 made of titanium-doped quartz glass. The gradient lens 52 has the form of a short cylindrical rod section, which is welded or spliced ​​to the distal end 32 of the optical waveguide 3. The light entry and exit surfaces of the gradient lens 52 are planar. In the embodiment shown in Figure 3a, the gradient lens 52 is configured to generate an exit cone 34 with a relatively small collimation angle 0, which leads to improved destruction or ablation characteristics of a solid 6 to be treated.

[0117] Figure 3b schematically shows the distal end 32 of an optical waveguide 3 comprising a lens 5 made of titanium-doped quartz glass. The lens 5 comprises a short cylindrical rod section which is welded or spliced ​​to the distal end 32 of the optical waveguide 3. The light-entry face of the lens 5 is planar. The light-exit face of the lens 5 is convex and gives the

[0118] Page 11 of 17 Applicant: biolitec Holding GmbH & Co KG

[0119] Our reference: BRG31223PCT

[0120] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0121] Date: November 5, 2025

[0122] Lens 5 has a focusing property, resulting in better destruction or...

[0123] The removal characteristics of a solid to be treated contribute to 6.

[0124] Figure 4a schematically shows the distal end 32 of an optical waveguide 3 comprising a gradient lens 52 made of titanium-doped quartz glass. In contrast to the gradient lens shown in Figure 3a, the gradient lens shown in Figure 4a exhibits a focusing emission characteristic.

[0125] Figure 4b schematically shows the distal end 32 of an optical waveguide 3 comprising a gradient lens 52 made of titanium-doped quartz glass. In contrast to the gradient lens shown in Figure 3a, the gradient lens shown in Figure 4b exhibits a collimating emission characteristic.

[0126] Figure 5a shows the cross-section through an optical waveguide 3, which comprises a multi-fiber device (multi-fiber optical waveguide) with several fibers 30 in a circular arrangement around a liquid supply device 4. The circularly arranged fibers 3 supply the laser light required for the fragmentation of concretions or stones, while the central liquid supply device 4 serves to create and flush a liquid environment at the treatment site, i.e., around the concretions or stones.

[0127] Figure 5b shows the cross-section through an optical waveguide 3, which provides a concentrically arranged fiber 30 for guiding the light emission to the treatment location. The fiber 30 is surrounded by a tubular liquid supply device 4. Spacers 40 hold the fiber 30 concentrically relative to the liquid supply device 4. Alternatively, several fibers, for example in the form of a fiber bundle, can also be arranged within the liquid supply device 4.

[0128] The laser according to the present device can be operated in both CW and pulsed modes. In a preferred embodiment, the laser operates in pulsed mode with higher pulse frequencies to enable faster ablation of solids such as stones and concretions. Preferred laser pulse frequencies or pulse packet repetition rates are between 1 kHz and 500 MHz, preferably between 1 and 200 MHz. High peak powers of up to 3 MW are used to increase ablation efficiency.

[0129] Page 12 of 17 Applicant: biolitec Holding GmbH & Co KG

[0130] Our reference: BRG31223PCT

[0131] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0132] Date: November 5, 2025

[0133] Figure 6 schematically shows the provision of laser pulses as pulse packets. Here, "At" represents the duration of a laser pulse, "f'" the repetition rate, "T" the pulse packet duration, and "T" the period of the pulse packet.

[0134] Figure 7 schematically shows the modular structure of a fiber laser. The radiation can have a wavelength in the range of 1700–2150 nm, preferably 1940 ± 20 nm. The laser and the laser fibers of the present invention can include tapered amplifiers to increase the beam quality and thus the treatment efficiency. The laser includes a main oscillator 23, which generates a continuous sequence of short pulses with a duration At from one picosecond to several hundred nanoseconds and a repetition rate f of 1 kHz (for example, for nanosecond pulses) and 1 GHz (for example, for picosecond pulses). The signal from the main oscillator 23 is acquired by a first amplifier 24 and then fed to an intensity modulator 25, which forms a packet with a duration and period T from a continuous sequence of pulses.The duration of a packet can vary from one nanosecond to 5000 milliseconds, preferably from 1 ps to 5000 ms, and most preferably from 1 ps to 1000 ms. The repetition rate of the packets can be between 1 kHz and 500 MHz, preferably between 1 MHz and 200 MHz. The optical signal after the intensity modulator 25 is amplified by the second amplifier 26 and then fed to a high-power, tapered, thulium- and / or holium-doped fiber cone amplifier 27. The general control of the operation of the laser and its components is carried out by a control unit 28, such as a control board. The amplified optical beam at the output of the high-power, tapered, thulium- and / or holmium-doped fiber cone amplifier 27 enters the optical waveguide coupling unit 22, where the amplified radiation is introduced into the optical waveguide 3.The optical waveguide 3 can be a single-mode or multi-mode fiber or an optical fiber bundle. The laser radiation is guided to the treatment site 7 by means of the optical waveguide 3.

[0135] Where applicable, all individual features shown in the exemplary embodiments can be combined and / or exchanged without leaving the scope of the invention.

[0136] Page 13 of 17 Applicant: biolitec Holding GmbH & Co KG

[0137] Our reference: BRG31223PCT

[0138] Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY

[0139] Date: November 5, 2025

[0140] List of references

[0141] 1 Device

[0142] 2 lasers

[0143] 20 laser fibers

[0144] 22 optical fiber coupling unit

[0145] 23 Main oscillator

[0146] 24 first amplifier

[0147] 25 Intensity modulator

[0148] 26 second amplifier

[0149] 27 high-performance fiber cone amplifiers

[0150] 3 optical fibers

[0151] 30 fibers

[0152] 32 distal end

[0153] 33 Sheathing

[0154] 34 exit cones

[0155] 4 Liquid supply device

[0156] 40 spacers

[0157] 5 lens

[0158] 52 Gradient lens

[0159] 6 Solids

[0160] 7 Treatment location

[0161] 0 acceptance angle

[0162] Pulse duration f Repetition rate Duration of pulse packet

[0163] T period

[0164] Page 14 of 17

Claims

Applicant: biolitec Holding GmbH & Co KG Our reference: BRG31223PCT Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY Date: November 5, 2025 Claims 1. Device (1) for destroying and removing solids (6), such as concretions, in the human or animal body, comprising: a laser (2) for generating light emission; an optical waveguide (3) for guiding the light emission from the laser (2) to a treatment site (7), wherein a proximal end of the optical waveguide (3) is coupled to the laser (2) and a distal end of the optical waveguide (3) is insertable into the human or animal body, wherein the light emission can exit at the distal end (32) of the optical waveguide (3); and a liquid supply device (4) for supplying a liquid medium to the treatment site (7), wherein the laser (2) comprises at least one laser fiber (20) configured as a tapered laser fiber (20).

2. Device (1) according to claim 1, wherein the laser fiber (20) comprises a tapered quartz fiber doped with thulium and / or holmium.

3. Device (1) according to claim 1 or 2, wherein light can be emitted by means of the laser fiber (20) at a wavelength in the range of 1920 nm to 1960 nm, preferably 1940 nm.

4. Device (1) according to one of the preceding claims, wherein the optical waveguide (3) comprises an optical fiber (30) or a plurality of optical fibers.

5. Device (1) according to one of the preceding claims, wherein the liquid supply device (4) comprises a tubular line which is integrated into or arranged on the optical fiber (3) and runs at least partially parallel to the optical fiber (3).

6. Device (1) according to one of the preceding claims, wherein a lens (5) is arranged at the distal end of the optical waveguide (3) to provide a defined beam angle of light emission from the distal end of the optical waveguide (3). Page 15 of 17 Applicant: biolitec Holding GmbH & Co KG Our reference: BRG31223PCT Title: METHOD AND DEVICE FOR THE DESTRUCTION OR REMOVAL OF STONES, CONCREMENTS AND OTHER HARD SUBSTANCES IN THE BODY Date: November 5, 2025 7. Device (1) according to the preceding claim, wherein the lens (5) is a gradient lens (52), wherein the gradient lens is spliced ​​to the distal end of the optical waveguide (3).

8. Device (1) according to claim 6, wherein the lens (5) is a mini diamond lens.

9. Device (1) according to any one of claims 6 to 8, wherein the lens (5) comprises titanium-doped quartz glass.

10. Device (1) according to one of the preceding claims, wherein the laser fiber (20), preferably an active fiber core of the laser fiber (20), has a numerical aperture between 0.02 and 0.25, preferably between 0.06 and 0.14, particularly preferably 0.

1.

11. Device (1) according to one of the preceding claims, wherein the laser (2) comprises tapered amplifier fibers to increase the beam quality.

12. Device (1) according to one of the preceding claims, wherein the laser (2) can emit light at a wavelength in the range of 1700 nm to 2150 nm, preferably 1920 nm to 1960 nm, particularly preferably 1940 nm.

13. Device (1) according to one of the preceding claims, wherein the light emission of the laser (2) is pulsed, preferably with a pulse duration between 1 and 999 picoseconds.

14. Device (1) according to the preceding claim, wherein the pulsed light emission of the laser (2) has a repetition frequency between 1 kHz and 500 MHz, preferably between 1 MHz and 200 MHz.

15. Device (1) according to any one of claims 1 to 10, wherein the light emission of the laser (2) is constant. Page 16 of 17

Images