DE10008557A1 - Device for thermal obliteration of biological tissue using intense laser radiation, where the device is split into a handpiece and a puncture shaft, the latter being easily removable to facilitate cleaning - Google Patents

Abstract

Device comprises two parts: a handpiece (102) and a rigid puncture shaft (103) with an optical window and inner diffuser element. The handpiece and shaft are detachably joined together using either a press-fit or locking connection, so that the puncture shaft can be exchanged at any point in time. The puncture shaft serves both to puncture the tissue and transmit the light into the tissue.

Description

Task

The invention relates to an application device for interstitial thermal obliteration of biological tissue with the help of high-performance light radiation, the Tissue puncture and light application with can be carried out in the same device and the shaft of the application device from one Fluid is flowing through.

State of the art

The use of light (especially laser radiation) for Generation of high temperatures for tissue coagulation has long been known as a surgical procedure. In particular the interstitial application of Laser radiation is becoming increasingly important. target of The process is controlled and as homogeneous as possible Heating of sufficiently large tissue volumes by the local absorption of laser radiation. At temperatures above 45 ° C it occurs depending on the Exposure time due to the denaturation of the tissue proteins irreversible thermal cell damage leading to immediate or delayed death of the affected tissue areas to lead. Thereby, in particular, the therapy is otherwise inoperable tumors possible. The denatured and dead tissue remains in the body (in-situ) and is broken down or encapsulated by pitting. Usually, lasers of the near infrared are used Wavelength range used (preferably the Nd: YAG laser at 1064 nm) because of the optical penetration depth is particularly large here.

In practice, special fiber optic cables are used coupled laser applicators or diffuser elements  positioned within the diseased tissue. The Laser applicators, such as those used for. B. from DE 38 13 227, DE 40 41 234, DE 197 39 456 and WO 96/07451 are known, have a diffuse or directional radiation of the laser light. This is achieved in that the one to be treated Object-facing end of the laser beam Optical waveguide roughened mechanically or chemically or the steel in one with the Fiber optic end connected scattered body becomes. In comparison to the so-called bare fiber Application significantly increased radiating surface will cause unwanted tissue overheating accompanying carbonization avoided. All known Laser applicators are more sensitive to them mechanical structure, so that usually special Catheter systems, also called enveloping catheters, in the diseased tissue must be punctured, which will eventually pick up the sensitive laser applicators. Such Systems are e.g. B. described in DE 41 37 983 and draw is characterized in that the object to be treated facing end of the beam-guiding optical waveguide in one closed at the front, for laser radiation transparent tubular sheath catheter, e.g. B. one on Object-side end airtight and liquid-tight sealed plastic tube, is arranged. In addition to the optimal radiation characteristics, the Cooling the active applicator zone as extreme emphasized advantageous because so the maximum applicable amount of energy can be increased significantly, without taking the risk of tissue carbonization. This means a significant increase in efficiency compared to the uncooled procedure, so that larger tissue volumes can be treated. The cooling takes place through A flow around the active applicator zone suitable fluid. As in US 5569240, DE 44 03 134 and  WO 9426184 described, the fluid can be directly into the Body tissues are released. Better control can be achieved if the cooling fluid over a coaxial or paraxial catheter channel according to the principle the countercurrent process back out of the body is brought out. Such workers or Combinations of applicators and workers are from DE 42 11 526, DE 42 21 354, DE 42 37 286 and WO 93/19680 known. The extension of the complete magnetic resonance compatible puncture set including Puncture needle, guidewire, dilation needle, Introducer and sheath catheter is in DE 196 14 780 described.

The systems described above are used for Sclerotherapy of soft tissue tumors in different Organs, especially in the liver, prostate and brain.

With the previously minimally invasive procedure the tumor is punctured through the skin first through under local anesthetic and imaging Control by means of X-ray computer tomography or Magnetic resonance imaging. Then in another Working step of the flexible sheath catheter in the Puncture channel positioned using a lock system and then the actual laser applicator was introduced. The therapy is monitored with temperature-sensitive imaging methods, preferably magnetic resonance tomography, as in DE 39 31 854 described.

Has proved disadvantageous in the procedure described however, it was found that when the blood flow was high Organs such as the liver or kidney a lot of the reintroduced energy through the bloodstream is transported away and is therefore lost, so that especially in the case of very large tumors, often several synchronous ones or asynchronous laser applications are required.  

It can also be caused by neighboring blood vessels asymmetry of the sphere of action. Both increases the risk of tumor cell proliferation and of leaving behind active tumor tissue.

description

Surprisingly, it was found that the interstitial thermal treatment of the body tissue with Laser radiation without increased risk for the patient can also be performed in open surgery. The doctor gains access through a skin incision to the target organ in which the tumor is located. Then the application system is positioned in the Body tissue preferably under imaging Ultrasound control. But also the open one Magnetic resonance imaging is becoming increasingly larger Importance, so that also open surgical interventions including laser sclerotherapy under magnetic resonance control can be carried out.

It has proven to be advantageous that supplying vessels of the organ partially or completely interrupt so that the blood flow in the target organ entirely or partially comes to a standstill. The blood supply can interrupted the entire time of the laser application or remain diminished and will only become effective after the Application or even after an additional waiting time restored. It turned out that through this Compared to an efficiency increase of over 50% the usual procedure was to be achieved, so that essential larger tumors can be treated or a Gaining time shortens the duration of the operation.

A similarly good increase in efficiency could surprisingly, even if the Blood flow rate of the organ to be treated by the  prior injection of perfusion-reducing substances interrupted in one of the supplying blood vessels or is reduced. The effect is based on the knowledge that the particles contained in the substances, preferably microscopic starch particles, due to their diameter do not pass through the capillary system of the affected organ can and therefore 'clog' it first. The Flow resistance increases significantly, so that the Total blood flow to the organ decreases. Furthermore the particles are designed so that after some Dissolve time, and so the normal blood circulation of the Ensure organ. In the case of the liver there is additionally by the optional injection of the substance in the venous and / or arterial supplying vessels selectively the possibility of using certain capillary systems To block.

Another advantage of the open surgical procedure proved the possibility of having small tumors imaging procedures cannot be diagnosed can, by manually scanning the organ localize and also deliver therapy. Other advantages are with the surgical procedure connected. Firstly, the range of indications be expanded because of the possibility of Intraoperative tumor sclerotherapy can be performed by a patient inoperable to be transformed into an operable situation so that z. B. a surgically non-removable tumor is thermally desolated by means of laser radiation, while one or more tumors of the same organ at the same time be surgically removed. On the other hand, tumors to be thermally desolated intraoperatively in which due to its location, a minimally invasive approach is out of the question.  

However, the handling of the known catheter and laser application systems proved to be problematic in the open surgical procedure. In particular, the separate use of puncture needle, sheath catheter, and laser applicator, which were specially developed for the needs of a puncture under X-ray tomographic control and subsequent laser therapy under nuclear spin tomographic monitoring, turned out to be extremely unfavorable. The disadvantages known to the person skilled in practice are as follows:

• 1. Especially in intraoperative procedures are common multiple tumors or one or more of the Tumors are so large that a repeated puncture and laser therapy required is. The main problem with the known puncture and application systems is that the Positioning of the overall system in several successive individual steps must take place. This procedure is extremely time-consuming and hides it Danger of undetected applicator destruction.
• 2. The positioning of the known flexible Catheter systems in particular in hard tumors often because of the compared to the minimal Invasive procedure only after a short puncture path repeated widening of the puncture channel possible, which takes an increased amount of time.
• 3. After positioning the flexible catheter system it can by the open surgical procedure to its kink in the area of the organ or Tumor boundary come so that when the Laser applicator this breaks what goes in unnoticed Result in an unpredictable energy distribution in the Tissue and eventually destroying the catheter leads. The catheter melts due to overheating  the tissue and can only be at high risk of bleeding under mechanical force from the tissue be removed.
• 4. The laser applicator can with the known systems only be inserted into the sheath catheter when this already has its final position in the body tissue has taken. This allows the exact position of the Laser applicator not inside the sheath catheter be checked visually, the only characteristic for the Position of the applicator within the sheath catheter is the mechanical stop of the applicator on distally closed catheter end. This procedure is extremely buggy, however, because a slight kink in the sheath catheter (see 3.) can pretend such an attack, but then what an incorrect position of the laser applicator in the Envelope catheter and thus corresponds in the body tissue.
• 5. The laser applicators are known in the Catheter systems not or only by one thin sealing lip with respect to its axial position in the Catheter fixed. Through the intraoperative procedure it can easily lead to an unnoticed shift of the Laser applicators come in the catheter so that the Energy input in the area of the tumor tissue does not increase whose complete desolation is sufficient. The consequence is that there is a tumor progression and the Patient may need to undergo another operation must be subjected.
• 6. The known catheter systems are in the open surgical conditions to control Puncture and positioning preferably used imaging ultrasound is only very low contrast, so that the exact position of the sheath catheter tip is not can be located safely. Knowing the location the sheath catheter tip is of crucial importance  Significance for the complete obliteration of the tumor. Inadequate therapy will result in a Tumor progression and the patient needs another one Undergo surgery.
• 7. during the actual laser application Monitoring the progress of therapy in open surgical procedure preferably with imaging Ultrasonic. For a good coupling of the Ultrasound head to the uneven organ surface reach are relatively high contact pressures required due to faults of the Enveloping catheter with a rupture of the inner Laser applicators can go hand in hand. Here too there is a risk of uncontrolled Energy delivery with catheter destruction and melting of the system on the tissue.
• 8. In addition, the imaging ultrasound only an inadequate means to the success of therapy to visualize. Because of the high applied Amounts of energy are temperatures of over 100 ° C in Tissue reached so that by the massive emergence of interstitial vapor bubbles and so on associated acoustic impedance jump a Assessment of therapy progress only is possible to a limited extent because of the So-called sound shadows occur.

The aim of the invention is therefore a Application device for thermal sclerotherapy of Body tissue by means of high-performance light radiation Realize both puncturing the tissue as well enables light application with just one device and thus the disadvantages of the current state of the art avoids the open surgical procedure.  

This object is achieved by a Application device according to claims 1 to 22 solved.

According to the invention, this application device consists of a pointedly closed, rigid, with one Counterflow flushing provided puncture shaft with internal diffuser element, and one with the Puncture shaft coupled handpiece.

The puncture shaft is in contrast to the known solutions according to the invention in at least one composite comprising two different materials construction realized. This results from three combining requirements, namely that the Puncture shaft sufficient stability and Have rigidity for direct puncture of the tissue the puncture shaft must be in its distal area over the length of the diffuser element transparent for the Laser radiation is and that the puncture shaft also at mechanical stress caused by bending forces does not break. None of the materials used so far unites them all three requirements, so that the solution according to the invention in the use of a rigid, for the used Laser wavelength transparent hollow cylinder, which over a wide area coaxially from one Stabilization jacket is surrounded. Preferably that is distal end of the stabilizing jacket is tapered designed so that the body tissue at the puncture can easily slide over its surface. The length of the Stabilizing jacket is dimensioned so that the protruding part of the transparent hollow cylinder Diffuser element can completely accommodate and thus the free radiation of the laser power into the tissue  is. As was surprisingly shown, could such a composite structure compared to the breaking strength a one-component system without affecting the function.

In a preferred embodiment, the Use of quartz glass or sapphire as transparent Hollow cylinder compared to the existing systems Removal improved by a factor of four allows excess heat from the tissue. Farther it was recognized that the high melting point of glass the thermal destruction threshold increased significantly is performed so that laser sclerotherapy is performed more safely can be. To give the user an orientation enable and a reproducible position of the To ensure puncture shaft in the body tissue the stabilization jacket preferably with equidistant Markers.

In another variant, which is also the one above advantages mentioned, the Stabilizing jacket also inside the transparent Hollow cylinder can be arranged.

In continuation of the inventive concept, the Stabilizing jacket in a third embodiment also movable over the transparent hollow cylinder be led. This allows the stabilizing jacket to be used the puncture of the body tissue in whole or in part the transparent hollow cylinder are pushed and so optimal protection against mechanical destruction guarantee. Immediately before the start of the Laser stabilization will stabilize the mantle in its Starting position withdrawn so that the laser radiation through the transparent hollow cylinder freely into the Can radiate tissue. For safe use  optionally the fixation of the stabilizing jacket relative to the transparent hollow cylinder in defined positions, preferably in the withdrawn as well as in the advanced Status. The movable stabilizing jacket offers in addition to the improved puncture the possibility of unintentional radiation from high energy Avoid laser power when undergoing therapy marginal smaller tumors the transparent part of the The puncture shaft is only partially located in the body tissue. As an additional advantage of the mobile Stabilizing jacket is to be noted that in the case thermal bonding of the body tissue with the transparent part of the puncture shaft Bonding by pushing the stabilizing jacket forward can be easily solved, according to the invention Body tissue facing end due to its conical Inlet has a very good shearing effect.

For atraumatic puncture of the body tissue is the Puncture shaft according to the invention with a tip provided, preferably by fusing the distal area of the transparent hollow cylinder is realized. Optionally, after the merger the additional grinding of the tip to achieve a better puncture effect. Alternatively or in addition can also be a tapered element, preferably made of Metal, ceramic or plastic, firmly attached to the distal Be connected end of the transparent hollow cylinder. It It should be noted that the puncture of Body tissues, especially under open surgical ones Conditions preferably with imaging ultrasound is monitored. In an expanded embodiment of the Invention is therefore the integration of one in Ultrasound image with medium representing high contrast, ideally in the area of the puncture shaft tip,  intended. Surprisingly, it was found that already the integration of an air bubble into the Puncture shaft tip due to the large acoustic Impedance transition between the body tissue or Puncture shaft material and the included Air bubble leads to a significant signal which the location of the puncture shaft tip in the Ultrasound image made considerably easier. Optionally, however also a special ultrasound contrast medium in the Puncture shaft tip can be integrated. In a alternative embodiment are in the transparent part the puncture shaft is filled with air parallel to the axis Capillaries integrated, which are also due to the acoustic impedance jump a good localization enable.

An essential feature of the application device is the flow through the puncture shaft with a preferably biocompatible fluid. Because of the good Thermal conductivity properties of the transparent hollow cylinder In contrast to known systems, the fluid can Room temperature are used and there are none special measures to increase the heat capacity or lowering the freezing point of the fluid required. To implement counterflow cooling the puncture shaft is designed at least double lumen, preferably with a centrally guided, thin-walled and for the laser radiation transparent tube, the Outside diameter is less than the inside diameter of the hollow cylinder and its length is such that its distal end at least 1 mm in front of the distal Closure of the puncture shaft ends. This can do that Fluid with a corresponding pressure difference caused by a external or laser-coupled pump system or a height difference between the storage vessel and the fluid drain  can be reached in the centrally guided hose flow to the distal end of the puncture shaft and in the free lumens flow back between the tube and the shaft. The task of the fluid is preferably Achieving a homogeneous temperature profile through targeted cooling of near-shaft tissue areas.

In a variant, the fluid is in a known manner scattering substance added to the Emission characteristics of the described below To improve the diffuser element. In a special Embodiment can even apply to the diffuser element entirely be dispensed with and that from the optical fiber prograd emerging radiation by the dissolved in the fluid light-scattering substance can be distributed homogeneously. In a Another variant is the fluid Ultrasound contrast media added to the localization of the entire shaft flowing through the body tissue Facilitate use of imaging ultrasound. In a further embodiment, the fluid is a Magnetic resonance contrast agents added to the Localization when used in the preferably open To facilitate magnetic resonance imaging.

Another essential feature of the invention is that Achieving a homogeneous radiation of the laser light over a defined length of the puncture shaft. For this a diffuser element known in principle with a defined length between 0.5 cm and 10 cm central positioned in the puncture shaft so that the entire length of the diffuser element in the area of the transparent Hollow cylinder lies. Preferably, as Diffuser element uses an optical fiber whose distal end in a known manner over the above specified length as volume spreader or as  Surface spreader is executed. In a preferred one The variant is the one that carries the diffuser element Optical fiber directly on its external, the Diffuser element with an opposite end standardized adapter so that the Optical fiber directly with the laser device or with an optical element upstream of the laser device (e.g. beam splitter) can be connected. Diffuser element and fiber optic are in the centrally inserted tube of the shaft and on the handpiece described below Application device fixed. The diameter of The diffuser element and optical fiber are dimensioned so that between the inner diameter of the central arranged hose and the outer diameter of the Optical fiber one for the flow of the fluid sufficient lumen remains free.

In another embodiment, the diffuser element and external fiber optic cable separately, so that no direct connection between the diffuser element and the laser or an optical upstream of the laser Element exists. Rather, the diffuser element along with a short, upstream Optical fiber permanently integrated in the puncture shaft. The Feeding the laser radiation into the upstream Optical fiber and thus in the diffuser element takes place in the range described below Handpiece provided coupling point by an external Optical fiber.

About the non-positive and form-fitting but detachable connection the puncture shaft with the one described below To ensure the handpiece is the puncture shaft with a preferably made of plastic or metal Provide connector. The task of the connector  is also the leadership of the centrally located Sehlauches and ensuring a suitable one Fluid flow within the puncture shaft and below described handpiece such that the fluid flow without Leakage and pressure loss with the free interior and The outer lumen of the puncture shaft is connected in such a way that a defined flow direction is established.

According to the invention, the puncture shaft described above in a permanent but detachable connection via the Connection piece to a multifunctional handpiece coupled. The tasks of the handpiece initially include in addition to ergonomic handling, the connection of all Fluid supply and discharge hoses, expediently using the usual quick Closure systems according to the prior art, as well as in Interaction with the connector the warranty a directed fluid flow within the handpiece and puncture shaft. Another task of the handpiece consists in the absorption and fixation of the laser light feeding optical fiber.

In the preferred variant of the fixed with the external Optical fiber connected diffuser element according to the invention provided with a central bore elastic seal on the fiber optic Entry opening of the handpiece provided, the Central bore a slightly larger diameter has, as a diffuser element and optical fiber. This makes it easy to insert the Optical fiber guaranteed. By tightening a threaded union nut the elastic seal compressed so that the Optical fiber after correct positioning of the Diffuser element in the shaft gas and liquid tight is fixed. In continuation of the inventive concept  the external fiber optic cable also permanently in the handpiece be fixed. This is preferably done by a Adhesive connection so that on the screw connection can be dispensed with.

In the variant with a separate diffuser element and external fiber optic cable is on the handpiece suitable coupling element provided. This serves on the one hand for the permanent but detachable connection of the external optical fiber on the handpiece and on the other hand to accommodate the short, the diffuser element upstream optical fiber piece.

A major advantage of the separate construction Puncture shaft and handpiece is the light one Interchangeability of the puncture shaft. So in one Variant of this in the sense of a disposable item according to Insert are disposed of, whereas the handpiece Resterilization process is fed. Furthermore can according to the invention with several shafts diffuser elements of different lengths and / or different diameters realized and for Be made available so that during an operation the shaft can be changed quickly and so one optimal adaptation to the intraoperative situation becomes possible.

In a particular embodiment, the entire Puncture shaft before use with a tight adjacent, distally closed, transparent, preferably from a temperature stable and good thermally conductive plastic sterile cover provided which either by the choice of his Diameter or by an additional fixation is firmly attached to the shaft. The Sterile cover can be applied after therapy deducted and destroyed, so that in the event of a  Contamination with viruses or especially foreign protein there is no danger for subsequent patients. The handpiece and puncture shaft itself can be Resterilization are supplied.

In a special embodiment, it applies prevent it during transportation, sterilization and Storage of the application device to a unintentional mechanical damage to the shaft or the operator is injured. For this purpose, the shaft or handpiece is in one stable but detachable connection, preferably as Bayonet lock, a stable protective cap attached to the interior of the shaft completely records. For better sterilizability of the inside the protective cap is optional Provide openings or slots.

Because of the insufficient informative value intraoperatively used ultrasound devices to monitor the current thermal damage condition of the body tissue a special feature of the invention that in a extended embodiment the point-by-point measurement of Tissue temperature at a defined radial distance from the diffuser element is possible. This parameter is for Assessment of the vital status of the cells, especially in the The marginal area of a tumor to be obliterated is large Importance. For example, on the edge of desolating tissue volume considering a any surgical safety hem to be observed a temperature of 60 ° C over a period of some Measured seconds, at this point one of 100% thermal desolation and the Laser application can be stopped when the position at the same time the greatest extent of what is to be desolated  Volume marked and based on a described Interruption of blood perfusion is an inhomogeneous Temperature distribution can be neglected. On the other hand, well below 60 ° C is sufficient Temperatures do not reach complete desolation ensure that, in this case, a persistence of Laser application is displayed.

For the purpose of precise temperature measurement at defined Positions within the body tissue is at the Application device according to the invention a special one Guide arm attached so that this in a 90 ° angle is inclined against the puncture shaft axis. A fastener is in turn on the guide arm slidably but fixable, which by a Long bore parallel to the shaft axis as Guide for targeted puncture with a temperature-sensitive probe. The guide arm is provided with equidistant markings so that the radial distance of the temperature probe from the shaft axis can be read and adjusted directly. The temperature sensitive probe is also advantageous with markings or a mechanical stop provided so that the axial position of the probe can be controlled. In addition, the temperature sensitive probe advantageous by a Screw clamp can be fixed in their guide hole. In a simplified version can also several parallel holes in the Fastener may be arranged, or the guide arm even a number of equidistant pilot holes have, so that a mechanical adjustment of the Fastener can be omitted.

In continuation of the inventive concept Tissue temperature not at selected points in the tissue only displayed, but actively on-line  Regulation of laser power used. For this, the measured temperatures either in the laser itself or in an additional electronic element processed further and in such a control signal converted that at at least one of the measuring points defined temperature is reached or maintained.

In a further embodiment variant, instead of Temperature the so-called autofluorescence of the tissue Excitation in the wavelength range 200 to 700 nm as Vital signs for the assessment of the complete thermal tissue obliteration. The reinforced or weakened appearance of certain fluorescence bands (e.g. NADH fluorescence) is a measure of the vital Tissue condition and can be used to control or regulate the Laser output power can be used.

A special feature of the application device is characterized in that in an advantageous Design variant all materials and Adhesives for sub-components and thus the overall system can be sterilized (e.g. gas sterilization, Steam sterilization). This allows the application device or parts of the application device be used several times.

A special feature of the application device is that in a special Variant of the entire system materials compatible with nuclear spin (e.g. Titanium, ceramics, glasses, plastics). So that Application device also in the new open Magnetic resonance imaging scanners are used which are a working enable under open surgical conditions and in Contrary to imaging ultrasound a better one  Image quality and above all a better assessment of the allow thermal desolation.

Advantageous developments of the invention are in the Subclaims marked and are below preferred along with the description Embodiments of the invention based on the figures shown in more detail. Show it

Fig. 1 is a schematic representation of the application device in the body tissue, together with the laser system, the cooling circuit, the ultrasonic unit and the measuring probe,

Fig. 2 is a schematic sectional view of the application device according to a preferred embodiment having a shaped by fusion of the transparent hollow cylinder shaft tip,

Fig. 3 shows a schematic section through the puncture with a movable shaft, the outside-lying stabilizing casing,

Fig. 4a, b shows a schematic section through the front region of the puncture shaft with an inserted shaft tip,

Fig. 4c shows a schematic section through the front region of the puncture shaft with opacification,

FIG. 5a is a schematic section through the fiber fixing in a variant with a continuous optical waveguide

Fig. 5b is a schematic section through the fiber fixing in a version with air or fluid coupling

Fig. 6 is a schematic representation of the sterile cover

Fig. 7 is a schematic representation of the stable protective cap

Fig. 8 is a schematic representation of the guide arm for the selective measurement of temperature or fluorescence

Fig. 1 shows schematically a laser system 100 to which an optical waveguide 101 is connected via a suitable adapter 117th The optical waveguide is fixed on the handpiece 102 of the application device according to the invention. The puncture shaft 103 is positioned within the body tissue 104 . To remove excess heat, the puncture shaft is flowed through in a countercurrent process by a fluid which is initially located in a storage container 105 , preferably a sterile packed infusion bag, and is conveyed via a hose 106 from a pump system 107 , preferably a peristaltic pump, to the application device. The backflow of the fluid takes place via a further hose 108 into a collecting container 109 . In a completely closed variant, storage container 105 and collecting container 109 can represent identical reservoirs. Typical flow rates for the fluid are in the range of 1 ml / min to 1000 ml / min. Furthermore, FIG. 1 shows an ultrasonic scanner 110, which rests on the body tissue and is connected to the ultrasonic apparatus 111. The imaging ultrasound enables the optimal positioning of the puncture shaft 103 in the body tissue and also allows monitoring of the therapy implementation. For the precise determination of the state of the tissue at selected positions within the body tissue 104 , a measuring probe 112 is mounted on a guide arm 113 of the application device, which is connected to a measuring device 114 . In an expanded embodiment variant, the control or regulation of the laser power takes place via a controlled system 115 . Isotherms 116 are shown to illustrate the basic temperature profile in body tissue.

Fig. 2 shows the preferred embodiment of an application device according to the invention for laser radiation. The puncture shaft 103 is formed according to the invention from a transparent hollow cylinder 1 , preferably made of quartz glass, which is firmly enclosed by a stabilizing jacket 2, preferably made of metal. The connection of both elements is preferably done by gluing, which contributes significantly to the stability and breaking strength of the puncture shaft. The distal end 3 of the stabilizing jacket is designed to be tapered in order to avoid tissue trauma during insertion.

Transparent hollow cylinder 1 and stabilizing jacket 2 are expediently brought together in a connecting piece 4 in order to establish the connection to the handpiece 102 and to ensure that no liquid can escape and the quick replacement of the puncture shaft is possible. The diameter of the puncture shaft is typically in the range 2 to 8 mm.

Centrally located in the puncturing stem 103 extends a thin-walled, transparent for the laser radiation used tube 5, the approximately 1 mm from the tip 7 of the puncturing stem 103 ends, so that a fluid 6 within the inner lumen of the hose 5 can reach the distal end of the puncturing stem 103, and in Lumen flows back between tube 5 and hollow cylinder 1 . This ensures optimal cooling of the puncture shaft 103, in particular in the area in which the highest temperatures occur.

The distal end of the puncture shaft 103 is formed by a tip 7 , which enables the shaft to be inserted easily into the body tissue and, in a preferred variant, is formed by thermal fusion of the transparent hollow cylinder 1 .

Typically, the length of the tip is 2-3 times the puncture shaft diameter. FIGS. 4a to 4c show further variants of the puncture shaft tip 7 and will be explained separately.

The diffuser element 8 for distributing the laser radiation in the body tissue is known in principle and is advanced centrally through the tube of the puncture shaft to the distal end. The laser light reaches the diffuser element via an optical waveguide 9 , which is firmly connected to the diffuser element 8 and merges into the external optical waveguide 101 outside of the application device. The transparent hollow cylinder 1 projects at least by the length of the diffuser element 8 from the stabilization jacket 2 in order to ensure the radiation of the laser radiation. In a preferred embodiment, the stabilizing jacket 2 is provided with equidistant markings 10 in order to ensure the targeted and reproducible positioning in the body tissue.

The puncture shaft 103 is coupled to the handpiece 102 via its connecting piece 4, preferably via a screw connection. This has two connecting pieces 11 and 12 for the inlet and outlet of the fluid 6 , preferably according to the known Luer lock principle. An internal distribution system 13 provides for the leak and pressure loss-free flow of the fluid 6 through the puncture shaft 103rd

To fix the optical waveguide 9 or 101 , a special clamping device is provided on the handpiece 102 at its entry opening. In the preferred embodiment, an elastic sealing ring 14 with a central bore can be compressed by a threaded union nut 15 in such a way that the optical waveguide 101 is locked in the central bore in an airtight and liquid-tight manner. The diameter of the opening is preferably approximately 2 mm and the opening of the union nut is designed to be tapered in order to enable the diffuser element to be inserted easily. This variant is particularly advantageous if the optical waveguide 101 is provided with the diffuser element 8 at its distal end and with a standardized laser adapter ( 117 ) at its proximal end. Variants of this embodiment are shown in FIGS. 5a and 5b, which are explained separately.

Fig. 3 shows a special embodiment of the puncture shaft ( 103 ), in which the rigid stabilizing jacket 2 'is not firmly glued to the transparent hollow cylinder 1 , but can be moved movably over the transparent hollow cylinder. In a preferred variant, feed and retraction take place by rotating the stabilizing jacket 2 ', the axial movement being predetermined by a spiral groove 16 in the region of the connector 4 '. The stabilization jacket is advantageously guided in the groove 16 with a fixing pin 17 which , at the same time, ensures that the stabilization jacket 2 'is fixed in any desired position by twisting.

FIGS. 4a and 4b show two variants in which the distal end of the puncturing stem is formed by a made of plastic or metal, conically 7 'or flattened 7 "extending tip which is fixedly connected to the transparent hollow cylinder 1.

FIG. 4c shows a variant in which a special lumen 18 is incorporated into the tip 7 , which receives a medium which is rich in contrast in the imaging ultrasound and thus facilitates the localization of the tip.

Fig. 5a shows an embodiment of the connection of optical fiber and the handpiece, wherein the optical waveguide is 9 or 101 fixedly connected to the diffuser element (8) and the fixing in the handpiece 102 is continuous through an adhesive compound 19. The optical waveguide is protected against mechanical damage by a kink protection 23 .

Fig. 5b shows an embodiment of the connection of optical fiber and the handpiece, is directly connected in which only a short section of optical fiber 9 to the diffuser element (8). The optical waveguide piece 9 is fixed in the handpiece 102 , for. B. fixed by an adhesive connection 20 . The laser radiation from the external optical waveguide 101 is coupled in via a short air or liquid path 21 , the external fiber advantageously being provided with an adapter 22 and kink protection 23 such that it can be screwed to the handpiece 102 . In order to keep the coupling losses low, the diameter of the external optical waveguide 101 is somewhat smaller than that of the internal optical waveguide 9 .

FIG. 6 shows a sterile cover 24 , which is pulled over the puncture shaft ( 103 ) before the puncture and is closed at its distal end. By choosing a suitable diameter or by a fixation (not shown here), the sterile cover 24 is connected tightly to the puncture shaft ( 103 ). PTFE is preferably used as the material, since it meets all requirements for transmission of the laser light, temperature stability and thermal conductivity. After laser sclerotherapy, the sterile protection 24 can be disposed of.

Fig. 7 shows a protective cap 25, preferably a metal-made or plastic cylinder that can be specifically attached to the application device during transport and storage. It is preferably attached to the handpiece ( 102 ) by providing the protective cap with a groove 31 which is pushed over one of the rinsing connections ( 11 , 12 ). Due to the oblique course of the groove 31 and a slight rotation of the protective cap, it can be fixed on the handpiece ( 102 ). The protective cap has optional openings 26 to ensure reliable sterilization of the application device.

Fig. 8 shows a guide arm 113, which is preferably made of metal. A fastening element 27 is slidably mounted on the guide arm. In a preferred variant, the guide arm 113 has equidistant markings 28 in order to lock the fastening element 27 at defined distances from the puncture shaft by means of the fixing screw 29 . The fastening element 27 has one or more bores in order to receive a measuring probe 112 for temperature or fluorescence detection parallel to the axis of the puncture shaft. In a preferred embodiment, the guide arm 113 is attached to the handpiece ( 102 ) by means of a clamping ring 30 .

reference numeral

100

Laser system

101

external fiber optic cable

102

Handpiece of the application device

103

Puncture shaft of the application device

104

Body tissue

105

Storage container

106

feeding hose

107

pump

108

return hose

109

Collecting container

110

Ultrasound scanner

111

Ultrasound machine

112

Measuring probe

113

Guide arm

114

Measuring device

115

Controlled system

116

isotherm

117

adapter

1

transparent hollow cylinder

2

,

2

'' rigid stabilizing jacket

3rd

distal end of the stabilizing jacket

4

,

4

'' Connector

5

tube

6

Fluid

7

,

7

',

7

" Top

8th

Diffuser element

9

internal optical fiber

10th

Markings

11

Connecting piece

12th

Connecting piece

13

Distribution system

14

Sealing ring

15

Cap nut

16

spiral groove

17th

Locating pin

18th

Ultrasound marking

19th

Adhesive connection

20th

Adhesive connection

21

Coupling point

22

adapter

23

Kink protection

24th

Sterile cover

25th

protective cap

26

opening

27

Fastener

28

Markings

29

Fixing screw

30th

Clamping ring

31

Groove

Claims (25)

1. Device for thermal sclerotherapy of biological tissue by means of light radiation according to the prior art, characterized in that the device consists essentially of two separable parts, a handpiece ( 102 ) and a dimensionally stable puncture shaft ( 103 ) with an optical window ( 1 ) and inside Diffuser element ( 8 ), which is locked but detachably connected by means of a non-positive and / or positive connection ( 4 ), so that the puncture shaft ( 103 ) can be replaced at any time. 2. Device according to claim 1, characterized in that the puncture shaft ( 103 ) is designed at least double-lumen, so that it is flowed through by a fluid ( 6 ) according to the countercurrent principle for cooling and / or improving the radiation characteristics. 3. Apparatus according to claim 2, characterized in that the transparent hollow cylinder ( 1 ) of the puncture shaft ( 103 ) is constructed from the group of materials comprising glasses, ceramics or plastics. 4. The device according to claim 3, characterized in that the transparent hollow cylinder ( 1 ) of the puncture shaft ( 103 ) is closed by a thermal melting method ( 7 ). 5. The device according to claim 3, characterized in that the end of the transparent hollow cylinder ( 1 ) by a formed from the metal, ceramic or plastic material group formed, pointedly shaped element ( 7 ', 7 ") is completed. 6. The device according to claim 4 or 5, characterized in that the rigid stabilizing jacket ( 2 , 2 ') of the puncture shaft from the metal, ceramic or plastic material group and the end facing the transparent part is tapered ( 3 ). 7. The device according to claim 6, characterized in that the rigid stabilizing jacket ( 2 , 2 ') is provided with equidistant markings ( 10 ). 8. Apparatus according to claim 6 or 7, characterized in that the rigid stabilizing jacket ( 2 ) is glued to the transparent hollow cylinder ( 1 ). 9. Apparatus according to claim 6 or 7, characterized in that in one embodiment, the rigid stabilizing jacket ( 2 ') is pushed over the transparent hollow cylinder ( 1 ) and can be fixed in different positions. 10. The device according to claim 6 or 7, characterized in that in one embodiment, the rigid stabilizing jacket ( 2 , 2 ') is attached within the transparent hollow cylinder ( 1 ). 11. Device according to one of the preceding claims, characterized in that the handpiece ( 102 ) has two connections ( 11 , 12 ) for the inlet and outlet of the fluid ( 6 ) and a further opening for the optical waveguide supplying laser radiation ( 9 , 101 ) . 12. The apparatus according to claim 11, characterized in that the laser radiation supplying optical fiber ( 9 , 101 ) on the handpiece ( 102 ) or puncture shaft ( 103 ) is fixed and the emerging laser radiation over a short air or fluid path ( 21 ) in the diffuser element ( 8 ) or an upstream of the diffuser element optical fiber piece ( 9 ) is coupled. 13. The apparatus according to claim 11, characterized in that the diffuser element ( 8 ) is fixedly connected to the laser light-transmitting optical waveguide ( 9 , 101 ) and diffuser element ( 8 ) and optical waveguide ( 9 , 101 ) through an opening of the handpiece to the distal end the puncture shaft ( 103 ) are advanced. 14. The apparatus according to claim 13, characterized in that the optical fiber ( 9 , 101 ) carrying the diffuser element ( 8 ) is fixed by a locking means ( 14 , 15 ) on the handpiece ( 102 ). 15. Device according to one of the preceding claims, characterized in that over the entire puncture shaft ( 103 ) a distally closed, close-fitting, preferably made of temperature-stable, transparent and highly heat-conductive plastic sterile cover ( 24 ) is drawn 16. The apparatus according to claim 15, characterized in that the sterile cover ( 24 ) is destroyed after carrying out the therapy. 17. Device according to one of the preceding claims, characterized in that in a special embodiment on the handpiece ( 102 ) or on the puncture shaft ( 103 ) a variably adjustable and provided with equidistant markings ( 28 ) guide ( 113 ) is attached such that parallel to Puncture shaft ( 103 ) at a defined radial and axial distance from the diffuser element ( 8 ) one or more measuring probes ( 112 ) can be positioned in or on the body tissue ( 104 ). 18. The apparatus according to claim 17, characterized in that the guide ( 113 ) locked together with the measuring probes ( 112 ) but detachably connected to the handpiece ( 102 ) or the puncture shaft ( 103 ). 19. The apparatus of claim 17 or 18, characterized in that the temperatures or radial temperature profiles measured with the measuring probes ( 112 ) are used for setting the power in the context of an on-line control ( 114 , 115 ) or for switching off the laser ( 100 ) become. 20. The apparatus according to claim 17 or 18, characterized in that the autofluorescence or radial autofluorescence profiles measured with the measuring probes ( 112 ) are used for setting the power in the context of an on-line control ( 114 , 115 ) or for switching off the laser ( 100 ) become. 21. Device according to one of the preceding claims, characterized in that for transport, storage and sterilization, a stable protective cap ( 25 ), the length of which extends beyond the puncture shaft length, is secured as protection against damage to the puncture shaft and as protection against injury. 22. Device according to one of the preceding claims, characterized in that all materials and adhesives used can be sterilized and are therefore reusable. 23. Device according to one of the preceding claims, characterized in that all used materials compatible with the Are magnetic resonance imaging.   24. Device according to one of the preceding claims, characterized in that a contrast agent is added to the fluid ( 6 ), which improves the representation of the puncture shaft ( 103 ) with an imaging method. 25. Device according to one of the preceding claims, characterized in that an air bubble ( 18 ) or a contrast medium ( 18 ) is preferably enclosed in the region of the tip ( 7 ) of the puncture shaft ( 103 ) in order to improve the ultrasound contrast.