RU2485921C1 - Method of electrochemical lysis of intraocular neoplasm - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to ophthalmology and can be applied for electrochemical lysis of intraocular neoplasm. Surface electrode -anode in form of net is applied on sclera in zone of tumor base projection. Vitrectomy, after which - retinatomy, with tumor exposure, are performed. Exchange liquid-air is carried out. Needle-shaped curved cathode, whose intratumoral part is introduced into tumor structure near base in zone of maximal blood supply by the data of ultrasonic examination, is introduced intravitreally, after that, in the similar way, but from the opposite side, introduced is second cathode in such a way, that intratumoral parts of cathodes are located inside tumor parallel to each other. After introduction of cathodes electrochemical lysis of tumor is carried out, when it is over the remnants of destructed tumor are removed.

EFFECT: method makes it possible to reduce risk of recurrences.

3 cl

Description

The invention relates to medicine, and can be used in ophthalmology and ophthalmic oncology for intraocular electrochemical lysis of intraocular neoplasms.

At the present stage of development of ophthalmic oncology, preference is given to organ-preserving methods of treatment of intraocular neoplasms.

In this regard, the method of electrochemical lysis (ECL) is of interest. The principle of ECL is based on the direct effect of direct current on the tumor: electrodes (anode, cathode) are injected directly into the tumor - with the occurrence of aseptic necrosis and delayed chemical exposure to the tumor by electrolysis products. The ECL process is not accompanied by an increase in temperature, which fundamentally distinguishes this method from radiofrequency, plasma and laser ablation.

It is known that the vessels that feed the intraocular neoplasm are located mainly near its base, closer to the sclera. Accordingly, for the effective destruction of the tumor blood supply system, the epicenter of the electrochemical destructive effect should be located in this zone, which requires a change in the traditional approach (parallel introduction of electrodes into the tumor structure perpendicular to its base) to the shape and location of the electrodes. In addition, for the targeted introduction of electrodes into the zone of interest, visual control is necessary, therefore it is advisable to introduce electrodes intravitreal.

A known method of ECL of large choroid melanomas (patent for the invention No. 2347547). In this method, needle electrodes are introduced into the tumor structure transsclerally in the area of the projection of the tumor onto the sclera. With this arrangement of electrodes, not all vessels supplying the tumor fall into the zone of their action, which significantly reduces the effectiveness of treatment. In addition, sclerotomy violates the integrity of the eyeball in this area, which can lead to the migration of tumor cells and, as a consequence, the germination of the tumor in the sclera.

The objective of the invention is to develop an effective method for electrochemical lysis of intraocular neoplasms.

The technical result is the preservation of the integrity of the sclera in the zone of projection of the base of the tumor, the electrolytic destruction of the tumor in its entirety with its complete removal, the absence of relapse and metastases in the long-term postoperative period.

The technical result is achieved due to the fact that:

1) the use of an electrode for ECL — an anode made in the form of a grid and corresponding in shape to the projection of the base of the tumor on the sclera, and smaller than the base of the tumor by 2 mm around the entire perimeter — eliminates the violation of the integrity of the sclera in the area of projection of the base of the tumor, which ensures prevention of tumor cell migration and tumor invasion into the sclera;

2) the use for ECL of two needle electrodes - cathodes that are introduced intravitreal into the tumor, through the slopes of the tumor, from two opposite sides, in the area of the highest blood supply to the tumor according to preliminary ultrasound so that the intratumoral parts of the electrodes are parallel to each other in the area of the base of the tumor , - provides complete destruction of the vascular system of the tumor while maintaining the integrity of the sclera;

3) conducting ECL with specified parameters leads to destruction of the tumor tissue, significantly reduces the risk of leaving viable tumor cells, dissemination of tumor cells during removal of the neoplasm, intraoperative bleeding;

4) intraocular removal of tumor decay products during ECL, as well as the removal of tumor residues after completion of ECL using a vitreotome, minimizes the risk of relapse and metastases in the long-term postoperative period.

To conduct electrochemical lysis by the proposed method, 3 electrodes are required: 1 anode and 2 cathodes.

The anode is made in the form of a grid of platinum wire with a diameter of 0.05 mm with a cell size in the light of 0.2 mm, in shape and size corresponds to the shape and size of the projection of the tumor base on the sclera. At an arbitrary point on the grid, a flexible electric wire is rigidly attached, the free end of which is designed to be connected to an ECL apparatus.

Each of the cathodes is intended for intraocular administration and is made in the form of a 32 G needle with a curved intratumoral part and a limiter in the form, for example, of a pin head. The radius of curvature and the length of the intratumoral part of the electrode are individually selected according to ultrasound, depending on the transverse size of the tumor at the proposed site of insertion of the electrode, so that, being introduced into the structure of the tumor on the one hand, the intratumoral part of the electrode does not come out of it on the other, but completely was inside the tumor. The electrode, with the exception of the intratumoral part, is coated with a bioinert electrical insulating material, for example fluoroplast-4. The electrode is located in a blunt cannula 23 G, containing a window to limit the stroke of the electrode stop. The length of the cannula should be sufficient so that the window to limit the stroke of the electrode stopper when using the electrode is completely extrascleral. At the extreme upper position of the limiter, the electrode is completely in the cannula; at the extreme lower position of the limiter, the electrode is advanced from the cannula by the amount of the intratumoral part. The electrode is made of a conductor that allows the intratumoral part to be in a straightened position inside the cannula and take a curved shape when exiting from it, for example, from an alloy Fe-Mn-Si or Fe-Ni, or Cu-Al, or Cu-Mn, or Co- Ni, or Ni-Al.

The method is as follows.

Preliminarily, according to the ultrasound data, the area of the greatest blood supply to the tumor and the depth of its location from the top of the tumor are determined.

At the preparatory stage for ECL, if necessary, rectus muscles are cut off to provide access. Transsclerally diaphanoscopically clarify the location and size of the tumor, determine the boundaries of the projection of the base of the tumor on the sclera and outline them with a coloring matter, for example, 1% aqueous-alcoholic solution of brilliant green. An anode is applied to the sclera in the area of projection of the base of the tumor and hemmed with 2 interrupted sutures to the sclera.

Perform a 3-port 23 G vitrectomy, after which retinotomy, exposing the tumor, conduct a fluid-air exchange. Next, a pars plana, 3.5 mm from the limb in the quadrant, which provides the most convenient access to the tumor, depending on its location, after the conjunctiva incision, sclerotomy is performed through which a 23G cannula with the cathode inside is introduced intravitreal, while the cathode limiter is in its highest position . The distal end of the cannula under visual control is brought to the tumor, the cathode limiter is moved to the lowest position and the intratumoral part of the cathode is introduced into the tumor structure in the place optimal for ECL: at the base of the tumor in the zone of the highest blood supply according to ultrasound data. In the same way, but from the opposite side, a second cathode is introduced through the opposite side of the tumor so that the intratumoral parts of the cathodes inside the tumor are parallel to each other.

After intraocular injection of cathodes, ECL of the tumor is carried out with a charge of 27-50 C. At the end of ECL, the remnants of the destroyed tumor are removed using a vitreotome, the retina is applied, endolasercoagulation of the retina is performed, and the vitreous cavity is filled with silicone oil. At the end of the procedure, the anode is removed. When cutting off the muscles, they are hemmed into place.

The invention is illustrated by the following clinical data.

ECL with intraocular introduction of electrodes by the proposed method was performed in 3 patients with large choroid melanomas (prominence - from 7.5 to 9.0 mm, maximum base diameter - from 10 to 14 mm) with a charge of 27, 38, 50 C, respectively . In all patients, according to the data of ultrasound dopplerography of the vascular system of the tumor in the regimes of energy and color Doppler mapping (EDC and CDK), a pronounced degree of vascularization (multiple color loci) with predominantly arterial blood flow in the area of the base of the tumor was determined in the projection of the neoplasm.

In all cases, the tumor was completely removed by the vitreotome. After ECL, the integrity of the sclera in the area of the base of the tumor in all patients was preserved.

By 3 months, ophthalmoscopically in all cases, a dense chorioretinal lesion with heterogeneous pigmentation, with a prominence of 0.3 to 0.5 mm, was determined at the site of the neoplasm according to the data of ultrasound B-scanning. According to the EDC and CDK, all patients had no blood flow in the projection of the focus. No relapses of the neoplasm and distant metastases were detected.

Thus, the present invention ensures the preservation of the integrity of the sclera in the zone of projection of the base of the tumor, electrolytic destruction of the tumor in its entirety with its complete removal, the absence of relapse and metastases in the long-term postoperative period.

Claims (3)

1. A method for electrochemical lysis of an intraocular neoplasm, comprising introducing electrodes into a tumor and performing electrochemical lysis, characterized in that first a surface electrode is applied to the sclera in the projection area of the tumor base in the form of a mesh — anode; then a vitrectomy is performed, followed by a retinotomy, exposing the tumor, conducting a liquid-air exchange, then a curved needle cathode is intravitreal, the intratumoral part of which is introduced into the structure of the tumor at the base in the zone of greatest blood supply according to ultrasound, after which in a similar way, but with on the opposite side, a second cathode is introduced so that the intratumoral parts of the cathodes inside the tumor are parallel to each other; after the introduction of the cathodes, ECL of the tumor is performed; after the completion of ECL, the remains of the destroyed tumor are removed. 2. The method according to claim 1, characterized in that the ECL of the tumor is carried out with a charge of 27-50 C. 3. The method according to claim 2, characterized in that after the remnants of the destroyed tumor are removed, the retina is put in place, endolasercoagulation of the retina is performed, the vitreous cavity is filled with silicone oil.