RU2536112C1 - Method for electrochemical treatment of scleral bed following endoresection of intraocular new growths - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to ophthalmology and ophthalmic oncology, and can be used for the scleral bed treatment following an endoresection of an intraocular new growth. To this effect, the endoresection of the intraocular new growth is followed by applying an active point of one needle electrode on the surface of a scleral bed in parallel to a retinotomy border at 0.5-0.7 mm therefrom. A second electrode is applied in parallel to the first one at 3-4 mm towards the centre of the scleral bed. An electrolysis is performed at current intensity 5 mA for 10 seconds. That is followed by moving the electrodes gradually along the surface of the scleral bed, first circularly in parallel to the retinotomy border, and then from the periphery to the centre. The electrolysis covers the entire area of the scleral bed at current intensity 5 mA for 10 seconds in each electrode position.

EFFECT: method enables avoiding the tumour cell survival on the scleral bed after the endoresection of the intraocular new growth and preventing developing remote postoperative recurrences and metastases.

Description

The invention relates to medicine and can be used in ophthalmology and ophthalmology for the treatment of the scleral bed after endoresection of an intraocular neoplasm.

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

Tumor endoresection, until recently, has been disputed as a treatment method because of the possibility of seeding by tumor cells, as well as the likelihood of systemic dissemination. Today it begins to be used more and more often in combination with brachytherapy, thermotherapy, photodynamic therapy. However, it is impossible to completely exclude the risk of seeding and dissemination. Therefore, it is urgent to develop a method for treating the scleral bed after endoresection of an intraocular neoplasm.

In this regard, the method of electrochemical lysis (ECL) (destruction) is of interest. The principle of ECL is based on the direct effect of direct current on tumor cells. Alkali and hydrogen are formed at the cathode, hydrochloric acid, oxygen, and chlorine are formed at the anode. The ECL process is not accompanied by an increase in temperature, which fundamentally distinguishes this method from radiofrequency, plasma and laser ablation.

The authors in publicly available sources failed to find a way to electrochemically treat the scleral bed after endoresection of an intraocular neoplasm.

The objective of the invention is to develop an effective method for the electrochemical treatment of the scleral bed after endoresection of an intraocular neoplasm.

The technical result is the exclusion of leaving viable tumor cells on the scleral bed after endoresection of an intraocular neoplasm, the absence of relapse of the tumor and metastases in the long-term postoperative period.

The technical result is achieved by the fact that after endoresection of an intraocular neoplasm, electrodes are applied to the surface of the scleral bed and electrochemical lysis is carried out, gradually moving them over the entire area of the scleral bed.

The technical result is achieved due to the fact that:

1) the use of curved electrodes allows you to freely manipulate them on the surface of the scleral bed;

2) conducting ECL in an air environment with specified parameters eliminates the risk of leaving viable tumor cells on the scleral bed and disseminating them with the subsequent development of relapses and distant metastases.

The method is as follows.

To conduct ECL, 2 electrodes are required: anode and cathode. In the inventive method, needle electrodes are used, the active part of which extends from the cannula at an angle that allows it to be freely applied to the surface of the scleral bed.

The electrode can be made, for example, in the form of a 32 G needle with a curved active part and a limiter in the form of, for example, a pin head. The radius of curvature and the length of the active part of the electrode are selected individually according to the ultrasound data depending on the size of the base of the tumor so that it can be applied to the surface of the scleral bed and moved along it, providing ECL throughout the entire area of the scleral bed. The electrode, with the exception of the active part, is coated with a bioinert electrical insulating material, for example fluoroplast-4. The electrode is located in a blunt cannula 25 G, containing a window to limit the stroke of the electrode limiter. 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 size of the active part. The electrode is made of a conductor, allowing the active part in a straightened position to be 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 electrode is platinum coated.

At the preliminary stage, the lens is removed, a vitrectomy is performed with the posterior hyaloid membrane removed, restrictive endolasercoagulation is performed around the tumor in three rows of coagulates, retinotomy is performed, the fluid is replaced with air. After that, the tumor is resected with its complete removal using the vitreotome until the scleral bed is exposed. Then, an additional illuminator (27 G or 29 G) is installed transsclerally 4 mm from the limbus, thereby freeing one surgeon's hand.

Then, through the existing sclerotomy, two 25 G cannulas with needle electrodes inside are intravitreal sequentially introduced, while the electrode stops are in the highest position. The visual end of the distal end of one cannula is brought to the edge of the retinotomy and, moving the electrode limiter to the lowest position, the active part of the electrode is placed on the scleral bed parallel to the edge of the retinotomy, 0.5-0.7 mm indent. Next, a second electrode is placed on the scleral bed, placing it parallel to the first, 3-4 mm indentation towards the center of the scleral bed. After applying two electrodes, ECL is carried out with a current strength of 5 mA for 10 seconds. By gradually moving the electrodes along the surface of the scleral bed, first in a circle parallel to the edge of the retinotomy, then from the periphery to the center, ECL is carried out over its entire area with a current of 5 mA for 10 seconds in each position of the electrodes. Upon completion of ECL, the vitreous cavity is filled with silicone oil.

The invention is illustrated by the following clinical data.

Example. Patient X., 59 years old. He entered the Kaluga branch of FGU MNTK "MG" with suspicion of the presence of an intraocular neoplasm of the right eye.

The examination was diagnosed with melanoma of the choroid (MX) OD (T ₃ N _o M _o ). The diagnosis was confirmed by fluorescence fundus angiography (FAG) and ultrasound B-scan. The neoplasm was localized in the posterior pole of the eye and had the following dimensions: base - 11 × 14 mm, height - 8 mm.

After tumor resection, the scleral bed was treated according to the proposed method.

ECL was performed using curved needle electrodes with a current strength of 5 mA for 10 seconds at each electrode position. The electrodes were moved 6 times, thus processing the entire area of the scleral bed. Upon completion of ECL, the vitreous cavity was filled with silicone oil.

In the remote postoperative period (3 years), when examining the fundus at the site of the removed MX, an atrophic lesion was detected with no signs of peripheral pigmentation. No relapses of the neoplasm and distant metastases were detected.

According to the proposed method, after endoresection of the tumor, the scleral bed was treated in 3 patients with large intraocular neoplasms. ECL was performed using curved needle electrodes with a current strength of 5 mA for 10 seconds at each electrode position. The electrodes were moved 3 to 6 times, thus processing the entire area of the scleral bed. Upon completion of ECL, the vitreous cavity was filled with silicone oil.

In the long-term postoperative period (from 1.5 to 3 years), in all cases, when examining the fundus at the site of a remote intraocular neoplasm, an atrophic lesion without signs of peripheral pigmentation was determined. Relapses of neoplasms and distant metastases were not detected in any case.

Thus, the claimed invention ensures the exclusion of leaving viable tumor cells on the scleral bed after endoresection of an intraocular neoplasm, the absence of relapse of the tumor and metastases in the long-term postoperative period.

Claims (1)

The method of electrochemical treatment of the scleral bed after endoresection of an intraocular neoplasm, which consists in the fact that after endoresection of an intraocular neoplasm, the active part of one needle electrode is placed on the surface of the scleral bed parallel to the edge of the retinotomy, 0.5-0.7 mm indent, and the second parallel to the first, indent 3-4 mm in the direction to the center of the scleral bed, and conduct electrochemical lysis with a current of 5 mA for 10 seconds, gradually move the electrodes on the surface of the scleral l Ms first circle, retinotomy parallel to the edge, then toward the center from the periphery, conducting ECL throughout its area with a force current of 5 mA for 10 seconds at each position of the electrodes.