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Bearing in mind that the pathological process in keratoconus starts with anterior corneal layers and is gradually progressing into inner corneal parts we put a question whether a pathological process can be stopped by affecting the anterior layers of the cornea. This paper presents the results of 5-year experience excimer laser surgery, a combination of photorefractive and phototherapeutic keratectomy (PRK + PTK) in the treatment of the initial keratoconus. The diagnosis of early keratoconus was based upon computed tomographic data, pachymetry in 5 points, and biomicroscopy of the cornea. The "firework" symptom a stromal ramification area that corresponds to the future apex of the keratoconus is described. PRK was performed with an ablation zone of 6 mm, and the transitional zone of 7 mm. The ablation zone in PhTk was dislocated towards the most ectasia--conical apex, topography and the apex site were predetermined of computed tomography. The PTK was performed with ablation zone of 8.00 mm and transitional zone of 9 mm. The described method allowed the authors to increase average uncorrected acuity of vision from 0.07 +/- 0.003 to 0.76 +/- 0.03. At the same time the acuity of vision was 1.0 in 69.2% of the eyes to enhance the mean corrected acuity of vision from 0.70 +/- 0.03 to 0.83 +/- 0.04. 2 by gradually progressing significantly to decline the degree of ametropia. The spherical component of refraction--myopia--decreased from 5.32 +/- 0.62 to 1.55 +/- 0.3 D. The cylindrical component of refraction myopic astigmatism reduced from 3.25 +/- 0.53 to 1.75 +/- 0.25 D. 3 to stop the progression of keratoconus in 91.3% of cases at a follow-up of 40.8 +/- 1.5 months (3 years 4 months) and at the maximal follow-up of 5.5 years. Thus, PRK + PTK with pathogenetically based, effective method in the treatment of the patients with initial keratoconus.

The paper is devoted to the actual problem of ophthalmology--removal of cysts and retinal detachments caused by cystoid retinal lesions. 3 stages of treatment are identified: stage 1 used YAG-laser dissection of the external wall of the retinal cyst with drainage of its contents. Stage 2 involved extrascleral filling reinforced by argon coagulation of the zone of the emptied cyst or by endolaser coagulation. Laser intervention was performed by the laser combine "Visulas-YAG II" produced by the firm "Karl Zeiss" (Germany) and fitted up by endolaser output. Coagulation energy was 0.2-0.7 W, the power of YAG-laser was 0.1-5.7 mJ with impulses of 120. Almost in all of the cases laser action was realized during one session. The laser's action was associated with hemorrhage in 11 cases (57.9%), and within 1 year of observations 2 relapses were noted (10.5%). YAG perforation of the external wall of a retinal cyst brings on its drainage and evacuation that is a perspective factor in subsequent surgical interventions during operations for retinal detachment due to cystoid degeneration.

The paper discusses the results of 28 laser operations carried out by bitoric nomograms and 18 operations carried out by monotoric nomograms for correction of high astigmatism (3 and more diopters) by laser in situ keratomileusis (LASIK). The patients' ages varied from 21 to 38 years. Eximer photokeratectomy was carried on a EC 5000 Nidek laser, lamellar section of the cornea was made with a Hansatome microkeratome. Bitoric keratoablation was carried out by an original method. Clinical refraction, visual acuity, and incidence of reoparations were evaluated in both groups 6 months postoperation. Differences in refraction and visual acuity were negligible. The incidence of reoparations in bitoric keratoablation was 25%, in monotic one 44%. Visual acuity with correction was higher after bitoric keratoablation of astigmatism. Hence, bitoric keratoablation is preferable for correction of high astigmatism by LASIK.

In this summing-up paper the authors discuss the results of surgical prevention and correction of progressive myopia carried out at Department of Ophthalmic Diseases of Russian University of Peoples' Friendship during two recent decades. Remote results of bandaging scleroplastic and reduced chondroplastic operations recommend scleroplastic interventions for prevention of myopia progress. Combined scleroplasty and cataract extraction stabilized the elongation of the antero-posterior axis of the eye and essentially improved visual acuity of 18-20 diopters. New variants of interlamellar operations are presented: tunnel-circular and fragmented circular, which are protected by patents of the Russian Federation. These operations are recommended for patients with stable myopia of 8-15 diopters after scleroplasty. Their advantage is low traumatism, absence of deep incisions on the cornea, wide optic center, possibility of regulating the refraction effect by replacing the implants or their complete removal without serious consequences for the cornea.

The paper for the first time presents statistically processed data on the cyclofusion reserves of subjects with normal binocular vision (25) for different age groups: adolescents aged 12-14 and adults aged 18-35 years. Two types of tests for evaluating cyclofusion under conditions of haploscopy (sinoptophore) are offered. The results can be used as a criterion for evaluating cyclofusion in various oculomotor abnormalities: squint, diplopia, and cyclotropia.

Research activities of Department of Ultrasound are carried out in cooperation with other departments of the institute. This paper sums up 30-year activities of the department on the utilization of ultrasound in ophthalmology with diagnostic and therapeutic purposes. Ultrasound is a highly informative diagnostic and effective treatment modality in various ocular diseases.

Reviews the results of correction of complex myopic astigmatism with asymmetric form of disposition on the cornea by two methods, with centered and decentered photokeratoablation. Analyzes the results of 80 laser keratomileusis operations for medium and high myopia. Describes a method of calculations and keratotopographic detection of asymmetric astigmatism and a method for transferring it into symmetrical form in computer-aided keratotopography. Two types of interventions brought about a good refraction result (sphere equivalent -0.66 +/- 0.54 diopters) and high resolving capacity of the eye (0.88-0.99). Decentered keratoablation led to a significant increase in visual acuity without correction, this indicating a better adequacy of this method, discussed in this paper.

The paper deals with progress of myopia during active growth of children. The strategy of treatment is developed and efficacy of surgical fortification of the sclera in children with an unfavorable course of myopia (early acquired myopia, rapid progress of the condition) is assessed. The proposed method stabilizes myopia for 3 years sclera fortification carried out in several stages in the patients with the most grave condition. Practical recommendations are offered concerning a certain order of exposures and indications for them.

The paper deals with the problem of treating ischemic diseases of the organ of vision by crossing the external branches of the carotid arteries. Methods based on the results of objective studies and verified in numerous operations are proposed. Experience gained in more than 250 indirect revascularizations of the eye demonstrates a high efficacy of the methods for defining the indications for ligature or crossing of the facial branches of the external carotid artery, thus recommending these methods for practical application.

The informative value of a method for assessing the degree of amblyopia, developed by the author, was assessed in examinations of 16 children (29 eyes) with ametropic amblyopia caused by high myopia and 41 healthy controls. The method consists in recording the pattern-reversal visual evoked potentials (VEP) evoked by 4 patterns of different checksize and contrast. A relationship has been revealed between the VEP types detected by the proposed method and the degree of amblyopia (degree of vision acuity loss). The author came to a conclusion that in ametropic amblyopia, similarly as in stimulus deprivation amblyopia, changes of VEP develop that reflect the deterioration of contrast sensitivity function in low spatial frequencies. The developed VEP method with the modifications described in this paper may be useful in the diagnosis and objective evaluation of the degree of amblyopia.

The paper deals with the treatment of severe congenital upper lid ptosis. In cases with the minimal mobility of the upper lid suspending operations are usually resorted to, those with suspending to Whitnall's ligament, among other things. Maximal resection of the levator muscle brought about encouraging results. The present paper describes the results of a modified operation: maximal resection of the levator with transposition of the muscle through Whitnall's ligament. A peculiar feature of surgical technique consists in preserving the intactness of the transverse ligament of the upper lid, crossing the lateral horns of the levator through the entire height, and transposition of the resected levator above Whitnall's ligament, this followed by suturing to the tarsal plate. The results of surgery were good. A better cosmetic and functional effect was attained than after common maximal resection of the levator; moreover, a lesser resection of the levator is needed in cases with the same degree of ptosis.

Trabeculodialysis, a new antiglaucoma surgical technique, developed at the Chair for Ophthalmic Diseases of the Yaroslavl Medical Institute, is described. Trabeculodialysis is aimed at recovery of intraocular fluid discharge via Schlemm's channel and then through orifices into intra- and episcleral vessels; this technique is indicated for patients with open-angle glaucoma in trabecular form of retention. Since 1990 this operation was performed in 50 glaucoma patients. The results will be presented in another paper.

The paper in devoted to a rare condition difficult to diagnose, intraocular lymphoma. Five patients with a disease history of 2 to 6 years were examined. The authors describe clinical features of the condition and histologic and electron microscopic findings. The clinical pattern of malignant intraocular lymphoma in polymorphous, therefore virtually every case with a sluggish uveitis or posterior scleritis resistant to common therapy has to be verified. A hematologist should take part in examination of such patients. Since the involvement is local, as our findings evidence, a course of polychemotherapy is necessary for such patients.

Gliomas of the optic nerve are more often in childhood and adolescence. The present paper analyzes the clinical features and diagnosis of optic nerve gliomas in 41 adult patients aged 15 to 56. Comparative analysis of the clinical picture and diagnostic specificities in optic nerve gliomas in adults and children has revealed a longer duration of the disease, less manifest exophthalmos and dilatation of the optic canal on the side of the tumor in adults. Analysis of computerized tomography data has prompted singling out 2 types of optic nerve glioma images: (1) spindle-shaped dilatation of the optic nerve in the orbit and (2) even thickening of the optic nerve along its whole length in the orbit. Each of these glioma tomographic images is associated with specific clinical features. Differential diagnosis between optic nerve gliomas and meningiomas in adults in described.

The paper concerns the studies into astigmatism development after penetrating wounds of the cornea depending on subjective and objective surgical factors. The attempt is made to design a set of measures aimed at the prevention of refractive complications upon the treatment of penetrating wounds of the cornea.