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The authors made a morphological study of the early proposed and clinically tested revascular optic nerve decompression operation developed to improve blood supply to the initial portion of the optic nerve in glaucoma-induced optic neuropathy. An experiment was carried out on 11 rabbits. The operated and control eyes were enucleated 1, 4, and 6 months after surgery. The experiment has established that muscle autografting into the retroscleral and paraneural space of the optic nerve is followed by a number of cellular reactions with the active participation of satellite cells, some of which may be associated with regenerative processes and presumably regarded as one of the cell autotherapy modalities.

A total of 45 patients (45 eyes) were operated on by using the technique of non-perforating deep sclerotomy (NDST). A conclusion on the action mechanism, efficiency and indications for NDST was made on the basis of determining the retention degree and of the intraoperative monitoring of tonometry and tonography parameters. Perforations of various scopes were proven to have an impact on the surgical hypotensive effect; finally, intraoperative measures were suggested in case of NDST inefficiency.

The visual functions and hemodynamics of the optic-nerve and retina were examined before and after decompression surgeries in the optic nerve. The methods of ophthalmodynamometry and ultrasound dopplerography were used to study the optic-nerve hemodynamics. The results showed an essential improvement in the visual field and blood circulation of the optic nerve in 80.7% of operated patients. The obtained data are indicative of that a disturbed blood circulation in the optic-nerve initial portion plays an important role in the development and progressing of glaucomatous optic neuropathy. Decompression surgeries in the optic nerve in cases of a progressing worsening of the visual functions are pathogenetically substantiated for glaucomatous patients.

Retrospective analysis of the efficiency of optic nerve decompression in progressive glaucomatous optic neuropathy in patients with normalized intraocular pressure showed widening and/or stabilization of the visual field in remote periods (6-11 years) in 83.3% patients. Study of the hemodynamics after optic nerve decompression showed a significant improvement of the hemodynamic parameters in the orbital artery-central retinal artery system: increased bloodflow velocity in the central retinal artery, increase of ophthalmic blood pressure and perfusion pressure, dilatation of the arteries, and constriction of veins, which indicates improvement of hemoperfusion in the initial portion of the optic nerve and retina after decompression surgery on the optic nerve. Extension and stabilization of visual field correlated with positive changes in circulation.

The technique of decompression surgery on the optic nerve in vascular atrophy has been developed. Optic disk staining grew more intensive, visual field widened, and vision acuity improved after such surgery. Results of fluorescent angiography of the fundus oculi and ultrasonic dopplerography evidence an essential improvement of the blood stream in the central retinal artery after the operation. The positive effect of surgery persisted over the entire follow-up period (8 months). The authors consider that enlargement of the inner diameter of the posterior scleral ring permits a more loose disposition of the vessels and fibers of the optic nerve in this ring, this being conducive to better circulation in the optic disk and retina.

The authors give theoretical grounds and experimental validation for surgery on the optic nerve to eliminate its atrophic changes in glaucoma. They suggest a technique of the direct intervention at the site of the optic disk, approaching it from the side of the eye cavity. A method for the optic nerve decompression at the site of its stem portion via an extraocular approach is suggested. Experimental studies have demonstrated the possibility of enlarging the volume of the optic nerve scleral canal by discission of its narrowest section, the scleral ring; this operation essentially decreases twisting and deformation of the nerve fibers and main vessels of the retina. Clinical results of decompression surgery in 32 patients with far-progressed glaucoma are analyzed. Improvement of the visual function and stabilization of the glaucomatous process were observed in all the patients both in the immediate and late postoperative periods. The retinal and optic nerve blood microcirculation were found to improve after the suggested decompression surgery.

Lymph microcirculation in the bulbar conjunctiva at the site of surgery was studied by fluorescent lymphangiography in 217 patients with primary glaucoma before and in various periods after trabeculectomy. Lymph vessels are changed after the operation; the pattern and intensity of these changes reflect the activity of cicatrization at the site of the operation and are closely related with the hypotensive effect in remote periods postoperation. In cases with the complete compensation of ophthalmic tone without extra hypotensive therapy a moderate narrowing of the lymph vessels was observed, parallelled by a compensatory increase of their quantity and of the volumic rate of the lymph flow. If the hypotensive effect of surgery was insufficient, an essential decrease of all the lymph flow parameters was observed, the most manifest in the patients with intraocular pressure still increased after extra drug therapy. A regular lowering of the lymph flow in 2-4 years after surgery was recorded; this lowering anticipated the deterioration of the hydrodynamic parameters. Noteworthy that ophthalmic tone failed to normalize when the mean diameter of the lymph vessels decreased more than twofold vs. the preoperative value. A conclusion is made that fluorescent lymphangiography holds good promise as a method for the assessment of the intensity of cicatrization processes after antiglaucoma surgery in order to timely prescribe preventive anticicatricial therapy. Administration of cytostatics in the postoperative period helps considerably increase the number of satisfactory outcomes of surgery due to suppression of cicatrization processes at the site of intervention. A lesser rate and intensity of cicatricial deformations of the lymph vessels was recorded in the patients administered cytostatics.