DE102004055412A1 - Medical laser system with vascular applicator consisting of radiation source, flexible light guide, and protective tube for insertion in blood vessel useful in vascular surgery has system for fixing light guide to flexible tube - Google Patents

Abstract

Medical laser system with vascular applicator consisting of radiation source (preferably laser), transparent transfer system for radiation source, flexible light guide, and protective tube for insertion in blood vessel or protective tube system for vascular surgery. The radiation source wavelength is preferably 800-1100 nm and its time of applicaion 10 millsecond to 10 seconds, and radiation can be continuous or pulsed. The light guide can be fixed to the protective tube. Independent claims are included for: (1) a system which can be sterilized by conventional means, e.g. ETO, plasma, formaldehyde, gamma radiation, or other low temperature process; (2) a device for relative displacement of the fiber used for fixing the light guide to the protective tube.

Description

Technical field of the Invention:

The Invention relates to the field of medicine, especially surgery, in particular the use of optical fibers in vascular surgery.

Next The classical method of vein stripping is becoming more and more popular the treatment by means of lasers in varices (varicose veins).

It become mainly Diode laser in the near IR range (800 to 1000 microns) used. The laser radiation is applied pulsed. Common are powers of 8 to 18 W and laser pulse lengths of 1s combined with pauses of 1s.

The Laser power is over Guided optical fibers with a core diameter of 200 to 800 microns. Most frequently In this case, an optical fiber with a core diameter of 600 microns is used.

These Optical fiber is over a catheter system placed in the blood vessel and during the pauses in the pulse Piece by piece from the Pulled out the vein.

The Catheter system becomes common in two lengths 450 and 900 mm used.

When The catheter system uses standard insertion protective tubes, their length on the for the application necessary dimension is increased.

• 1. Hautdesinfektion des zu behandelnden Beines. Ultraschallkopf in sterile Hülle geben.
• 2. Perkutane Punktion der Vene unter sonographischer Kontrolle
• 3. Der Führungsdraht wird durch die Kanüle in die Vene eingebracht.
• 4. Wenn der Führungsdraht richtig positioniert ist, wird die Kanüle entfernt. Der Führungsdraht verbleibt in der Vene.
• 5. Die Länge des verwendeten Katheters wird an der Lichtleitfaser mit sterilem Klebeband markiert.
• 6. 10 bis 20 mm hinter der ersten Markierung wird der Lichtleiter mit einem zweiten Klebeband markiert.
• 7. Der Katheter mit eingesetztem Dilatator wird nun über den Führungsdraht in die Vene eingebracht.
• 8. Führungsdraht und Dilatator werden entfernt. Katheter unter sonographischer Kontrolle in der Vene positionieren.
• 9. Mittels 3-Wege Ventil am Katheter kontrollieren, ob Katheter mit Blut gefüllt ist (Aspiration mittels Spritze). Bei Bedarf mit steriler Salzlösung spülen.
• 10. Alle anwesenden Personen müssen die Laserschutzbrillen aufsetzen.
• 11. Laser-Lichtleiter an das Lasergerät anschließen.
• 12. Den Lichtleiter bis zur ersten Markierung in den Katheter einführen. Nun ist die Spitze des Lichtleiters auf gleicher Höhe mit der Spitze des Katheters.
• 13. Ultraschallunterstützte Positionierung der Spitze des Katheters und des Laser-Lichtleiters 1–2 cm vor der Einmündung in die Vena femoralis.
• 14. Laser in 'Bereit' Modus schalten. Dadurch wird der rote Pilotstrahl aktiviert.
• 15. Laser-Lichtleiter festhalten, die erste Markierung entfernen und den Katheter bis zur zweiten Markierung herausziehen.
• 16. Erneute sonographische Kontrolle der Position der Laser-Lichtleiterspitze (1–2 cm vor der Einmündung in die Vena femoralis). Äußerliche Sichtkontrolle der Position des Laser-Lichtleiters durch den roten Pilotstrahl.
• 17. Sicherung des Laser-Lichtleiters am Katheter mit sterilem Tape. Dadurch wird verhindert, dass während der endovaskulären Behandlung der Lichtleiter alleine herausgezogen werden kann.
• 18. Bei der Durchführung unter Lokalanästhesie wird nun ein entsprechendes Anästhetikum verabreicht. Die Wahl des Lokalanästhetikums obliegt dem behandelnden Arzt.
• 19. Abschließende ultraschallunterstützte Kontrolle der Position der Laser-Lichtleiterspitze in der Vene (1–2 cm vor der Einmündung in die Vena femoralis). Gegebenenfalls kann der Patient am Kopfende abgesenkt werden. Dies ist hilfreich bei großen Venendurchmessern.
• 20. Am Laser werden die typischen Behandlungsparameter eingestellt:
• – Wiederholter Puls Modus
• – 12 Watt Laserausgangsleistung
• – 1 Sekunde Puls
• – 1 Sekunde Pause
• 21. Licht im Behandlungsraum dimmen. Dadurch wird die Erkennbarkeit des roten Pilotstrahls im Bein noch verbessert.
• 22. Mit den Fingerspitzen Druck auf das Bein ausüben. Die Finger am Bein so platzieren, dass der rote Pilotstrahl direkt vor den Fingern noch sichtbar ist.
• 23. Laserstrahlung mit Fußschalter freigeben und Katheter und Lichtleiter gleichzeitig herausziehen. Der Katheter und Laser-Lichtleiter werden nur in der Pause in etwa 2–3 mm herausgezogen. Somit ergeben sich 3–4 Laserpulse pro cm behandelter Vene. Das ergibt eine Dosis von 36–48 Joule pro cm.

The following describes the typical procedure of a prior art endovascular laser therapy:

• 1. skin disinfection of the leg to be treated. Place the ultrasound probe in a sterile sheath.
• 2. Percutaneous puncture of the vein under sonographic control
• 3. The guidewire is inserted through the cannula into the vein.
• 4. When the guidewire is properly positioned, the cannula is removed. The guidewire remains in the vein.
• 5. The length of the catheter used is marked on the optical fiber with sterile tape.
• 6. 10 to 20 mm behind the first marking, the light guide is marked with a second adhesive tape.
• 7. The catheter with inserted dilator is now inserted over the guidewire into the vein.
• 8. Guide wire and dilator are removed. Position the catheter in the vein under sonographic control.
• 9. Using a 3-way valve on the catheter, check that the catheter is filled with blood (aspiration using a syringe). If necessary, rinse with sterile saline solution.
• 10. All persons present must place the laser goggles.
• 11. Connect the laser light guide to the laser device.
• 12. Insert the light guide into the catheter to the first mark. Now the tip of the light guide is level with the tip of the catheter.
• 13. Ultrasound-assisted positioning of the tip of the catheter and laser light guide 1-2 cm from the junction with the femoral vein.
• 14. Switch the laser into the ready mode. This activates the red pilot beam.
• 15. Hold the laser light guide, remove the first mark and pull out the catheter to the second mark.
• 16. Renewed sonographic control of the position of the laser fiber tip (1-2 cm before the opening into the femoral vein). External visual inspection of the position of the laser light guide through the red pilot beam.
• 17. Securing the laser light guide to the catheter with sterile tape. This prevents that during the endovascular treatment of the light guide can be pulled out alone.
• 18. When performing under local anesthetic now a corresponding anesthetic is administered. The choice of local anesthetic is up to the attending physician.
• 19. Final ultrasound-assisted control of the position of the laser fiber tip in the vein (1-2 cm before the opening into the femoral vein). If necessary, the patient can be lowered at the head end. This is helpful for large vein diameters.
• 20. The laser sets the typical treatment parameters:
• - Repeated pulse mode
• - 12 watts of laser output
• - 1 second pulse
• - 1 second break
• 21. Dim light in the treatment room. This further enhances the visibility of the red pilot beam in the leg.
• 22. Apply pressure on the leg with your fingertips. Place the fingers on the leg so that the red pilot beam is still visible directly in front of the fingers.
• 23. Release laser radiation with footswitch and pull out catheter and light guide at the same time. The catheter and laser light guide are pulled out only in the break in about 2-3 mm. This results in 3-4 laser pulses per cm of treated vein. This results in a dose of 36-48 Joules per cm.

In addition to the catheters described above There is also the possibility to work with a simplified version. This consists only of the cannula, the guide wire and a protective tube. After inserting the protective tube into the vein, the light guide is pushed directly into the protective tube. It is dispensed with the dilator and the hemostasis valve. The difficulty in marking and the correct positioning of the optical fiber in the protective tube is retained even in this variant.

The described surgery takes place under sterile conditions. It should therefore all necessary for the operation preparatory steps be reduced to a minimum. The biggest handling problem arises during surgery the correct fixing of the light guide is.

The Correct position of light guide to protective hose is safety relevant, as explained below.

At the Introduce the fiber in the vessel is necessarily necessary that the distal end of the light guide is not out of the Protective tube looks out. One out of the protective tube outstanding Optical fiber is a big one Security risk for the patient, as during the displacement of the vessel applicator (protective tube with internal light guide) in the vessel, the vessel wall can be easily perforated.

Before however, the laser radiation needs to be applied to the distal end defined by the light guide protrude from the protective tube to to avoid irradiation of the light guide itself. This would be for reduce the light output impinging on the vessel wall. On the other hand it can be due to absorption of the directly exiting or scattered light from the protective tube to warm it up come to the burn. This in turn can cause thermal or mechanical damage of the vessel up to a vascular occlusion and / or injury of the surrounding twill tissue to lead. The fixation of light guide and protective tube to each other must while maintained throughout the irradiation period, wherein the vessel applicator manually step by step Step pulled out of the vessel becomes. Thus, both during insertion into the vessel as well when irradiated, the relative position of the distal end Protective tube and light guide always be defined and fixed.

The state of the art is the removal of blood vessels by means of light. In this case, the irradiation of the vessel takes place through the skin surface, at a wavelength which is relatively transparent to the skin but is well absorbed by the hemoglobin of the blood (selective photothermolysis, see eg US 5,749,868 ). A disadvantage of this method is that usually a high irradiation intensity is necessary. Furthermore, this method is limited to smaller diameter blood vessels that are not located too deep below the surface of the skin. For deep vessels of larger vessel diameter, the coagulation of the vessel wall must be from within, typically with a laser probe inserted into the blood vessel. This method is known as endovascular technique (see for example US 6,398,777 ). Usually you do not introduce the light guide directly into the vessel but uses a flexible protective tube for insertion. However, there are cases known from clinical use in which the optical fiber had retreated during the irradiation of the vessel in the vessel applicator. The protective tube burned off and an embolic death occurred for the patient. The aim of the invention is to prevent this.

Out Patent WO 02/102266 discloses a solution to this problem. Two markings are applied to the optical fiber at the factory, wherein a mark is the position of the distal end of the light guide during insertion and the second mark indicates the position of light emission. This solution has the disadvantage that the position is incorrectly set if later for example by reworking at the fiber end or shortening of the protective hose the length of the light guide and / or protective tube changes. In addition, the relative Change the position of the fiber optic cable and the protective tube during extraction Fiber and protective hose against each other only by manual holding be fixed.

None the previously known vessel applicators own a possibility for fixing the light guide to the protective tube at the same time Positioning.

The Invention describes a simple way to fix and Positioning of the light guide to the protective tube. The found solution is designed to be a vascular applicator system arises, with the fixation and positioning either by realized a special light guide or the protective tube becomes.

With the solution found the handling is noticeably easier and the treatment will be for the Patients much safer.

detailed Description of the invention with exemplary embodiments

The Invention will be explained in more detail with reference to an embodiment.

In the associated Drawings show:

1 the schematic diagram of the arrangement according to the invention in a first embodiment variant,

2 shows a special embodiment in which the fixing device is located on the protective tube,

3 shows a special embodiment in which the fixing device is located on the light guide,

4 a special embodiment variant of the fiber fixer,

5 a telescopic displacement device.

1 shows the structure of the special vessel applicator system consisting of light guide 1 , Fiber fixer 2 , Hemostasis valve 3 and protective hose 4 , All connection points 5 are in this example designed as luer or luer lock connections. Luer connections are introduced and known in medical technology and in particular in catheter technology. Furthermore, there are a variety of items with this type of connection by default. It is thus possible similar to a modular system to build inexpensive and tailored to the application systems.

The used items must be designed so that they are in the individual or even in the system sterilize.

Modifications of the system are conceivable. So it is possible to dispense with the use of the hemostasis valve or even a dilator as an insertion aid for the protective tube 4 to integrate into the vascular applicator system.

optical fiber 1 and fiber fixer 2 must be adjusted to each other so that the optical fiber is securely clamped in the fiber fixer, sealed in the hemostasis valve and guided in the protective tube. A particularly suitable combination for the vascular applicator system is an optical fiber with 600 μm core diameter with an outer diameter of approximately 1 mm, a 5F catheter system and a hemostasis valve with a possibility of sealing from 0 to 1 mm.

For handling with the vascular application system, it is crucial that the optical fiber terminates during the positioning phase with the protective tube or is reset in it, so that it does not come during this phase to injuries of the vessel wall. During the laser phase, the light guide must protrude from the protective tube. The distance of the free space should be kept as low as possible to allow the greatest possible protection for the light guide end. The reduction of the distance is limited mainly by scattered radiation of the laser. This scattered radiation can heat up the distal end of the protective tube to such an extent that it causes burns to the protective tube. It is therefore necessary, depending on the laser power used, to realize a distance of 5 to 40 mm from the distal end of the optical fiber to the distal end of the protective tube. If the entire protective tube or the distal end of the protective tube is made from a material which is as transparent as possible for the laser wavelength, eg PTFE or PA or similar material, the distance can be reduced and thus the handling even safer. The minimum clearance Fmin of the distal light guide can be derived from the following relationship: F min = F Max × (P / P Max ) where F _{max is} the maximum free-standing, P the laser power used and P _max the maximum possible laser power for the application. F _max is about 40 mm for optically non-transparent protective tubes and about 20 mm for optically transparent protective tubes.

The Positioning phase is using imaging techniques, z. Ultrasonic, NMR or a comparable established in medical diagnostics Procedures constantly checked. It is therefore very advantageous the light guide and or the protective tube to be designed so that he z.b. clearly visible under ultrasound control is.

In 2 a special design option is shown.

On the protective hose 4 is the fiber fixer 2 connected capable of securely clamping the inserted optical fiber. The use of the hemostasis valve 3 is possible but not mandatory. The connection points 5 can be realized with particularly suitable luer compounds or as insoluble compounds.

With this solution can be the fixation of the light guide 1 make sure. The exact positioning of the light guide to the distal end of the Protective hose can not be reached automatically.

The for the Positioning necessary distances have to also be measured with this variant or by markings on the optical fiber analogous to the patent US 2003/0078568 will be realized. In this case, the main problem is the unintentional Pulling out the light guide solved.

3 shows a further embodiment possibility. On the light guide 1 is the fiber fixer 2 already attached at the correct distance for the protective hose used.

The vessel applicator system is designed to provide a simple and secure connection 5 to the fiber fixer 2 is possible. In this case, a secure connection between fiber 1 and vascular applicator system realized without the doctor having to measure the length of the fiber.

Of the Fiber Fixer is designed so that the light guide easy to solve and to fix it. The light guide is already using the for the positioning phase necessary situation of Faserfixierers delivered. After completion of the Positioning phase, the light guide is released by the doctor and the Protective hose around the needed length compensation pushed back on the light guide and fixed again. Subsequently can be started with the irradiation.

Become Light guide refurbished changes their length. Since the fiber fixer not insoluble connected to the light guide, it is thus easily possible that necessary measure of length over the Adjust the fiber fixer and then sterilize the light guide. For the The surgeon is thus again a simple and safe treatment tool for Available.

In 4 is a concrete example of a Faserfixierer shown. This variant is a detachable fiber fixer. The clamping screw 9 is released and the light guide through the implementation 8th plugged. The light guide is placed in the fiber fixer so that it has the exact position for use. Subsequently, the clamping screw 9 locked. The clamping device 6 is made of soft silicone. By tightening the clamping screw 9 this deforms and clamps the light guide in its bore. The advantage of this clamping device is the possibility of simultaneous sealing and the fact that the clamping device made of silicone hardly exerts mechanical stress on the light guide. Further, the fiber fixer has a junction 5 which allows easy connection with the protective tube or the hemostasis valve. Due to the special type of clamping device, it is possible in contrast to conventional collet systems to lock a very large range of light guides, for example 100 μm to 1500 μm, with one and the same fiber fixer.

5 shows a special embodiment with telescopic sliding device 10 , It is particularly advantageous, the fiber fixer 13 constructive to execute so that he has the possibility with a telescopic displacement device 10 to be combined. The telescopic displacement device 10 realizes the necessary length compensation of up to 40 mm between positioning phase and irradiation phase via stop 11 respectively. 12 ,

Especially It is advantageous that it designed the attacks so constructive are that a lock in the corresponding layers are possible.

at the use of the described displacement device, it is possible the Fiber fixer with a permanent one Make connection on the light guide, since the release of the Fiber fixer for the laser phase can be omitted.

Of further it is possible the fiber fixer, the hemostasis valve or to construct the protective tube so constructively that these parts already include a displacement device.

1

optical fiber

2

Faserfixierer

3

hemostasis valve

4

Conduit

5

joints

6

clamper

7

cone

8th

execution

9

clamping screw

10

telescopic shifter

11

attack

12

attack

13

Faserfixierer

Claims (18)

Medical laser system comprising a vascular applicator, comprising a radiation source (preferably a laser), a transmission system transparent to the radiation of the radiation source, a flexible light guide and a protective tube or protective tube system for vascular surgery that can be inserted into the blood vessel, wherein the wavelength of the radiation source is between 700 and 1200 nm and preferably between 800 to 1100 nm, the irradiation duration of the radiation source is 10 ms to 10 s, the operating mode of the radiation source is continuous or pulsed, and the power of the radiation source is 0.5 to 50 W, preferably 5 to 20 W, and the diameter of the light guide is 0.1 to 2 mm, preferably 0.2 to 1 mm, characterized in that the light guides and / or the protective tube is equipped at least with the possibility of fixing the light guide to the protective tube. Arrangement according to claim 1 wherein the vessel applicator system is designed to be treated by conventional means such as ETO, plasma, Formaldehyde, gamma radiation or comparable low temperature processes is sterilizable. Arrangement according to claim 1 wherein the fixation located on the protective tube. Arrangement according to claim 1 wherein the fixation located on the light guide. The fixation consists of a fiber fixer, the preferably from a device for passing the light guide, a Clamping device and a fastening device to the protective tube or the light guide exists. The connection between fiber fixer and protective hose is preferably over realized a Luer or Luer Lock connection. The protective tube whose distal end consists of a for the Laser wavelength largely transparent material. The protective hose consists of polyethylene, Teflon, FEP or another for the wavelength of light transparent hydrofluorocarbon compound. The protective tube is a catheter system. The fixing device is such that it at the same time serves as a positioning device. Arrangement according to item 10, wherein the fixing device is such that the distal end of the light guide is not from the distal end of the protective tube looks out. Arrangement according to item 10, wherein the fixing device is such that it can be easily solved with imported vessel applicator and a defined displacement of the protective tube with subsequent refixing allows to the light guide. The fixing device is such that it simultaneously serves as a marking device. An apparatus according to claim 1, in addition to Fixing system means for relative displacement of the fixed Fiber for protection hose allows. Apparatus according to claim 14, wherein the displacement by a specified length he follows. The displacement is between 0 and 40 mm, preferably between 10 and 30 mm. Apparatus according to claim 14, wherein the displacement continuously between 0 and 40 mm, preferably between 10 and 30 mm takes place. Apparatus according to claim 14-16, wherein the amount is displacement depends on the applied laser power. The device of claim 14, wherein the fiber fixer unsolvable can be connected to the light guide.