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A total of 78 patients (143 eyes) with low, medium and high degree myopia were assessed. Apart from standard ophthalmological tests, flowmetry and duplex ultrasound of ocular vessels were performed in all cases to evaluate volumetric and velocity parameters of ocular blood flow in relation to the length of anterior-posterior axis and the degree of myopia. It is found that both parameters of regional blood flow progressively decrease as the anterior-posterior axis increases.

The article observes the results obtained by different electrophysiological methods in a variety of diseases: cataracts (192 eyes with different lens density measured objectively), antiphospholipid syndrome (50 patients with primary and secondary forms of the disease), different non-glaucomatous optic neuropathies (188 eyes), visual analyzer impairment of unknown etiology (85 eyes). Threshold of electrical sensitivity, lability of visual analyzer, and retinocortical conduction time can be measured regardless of cataract maturity and lens opacification intensity. The appearance of Ganzfeld electroretinogram, high-frequency rhythmical electroretinogram, macular electroretinogram, and flash visual evoked potentials alters with cataract development, thus complicating their interpretation. Different electrophysiological methods can be successfully combined to facilitate recognition of antiphospholipid syndrome, its differential diagnostics and monitoring. Evaluation of visual evoked potentials is crucial for an immediate and accurate diagnosis in patients with optic neuropathies. In complicated cases multifocal electroretinography and registration of multifocal visual evoked potentials can help differentiate retinal pathology with involvement of more proximal visual structures and, for the purpose of precise diagnosis, develop the most rational algorithm of further examination.

Characteristics of ocular blood flow (OBF) in primary open-angle glaucoma (POAG) in eyes with optic disc drusen have been investigated. The study enrolled 21 patient (35 eyes) with optic disc drusen, of which 7 (8 eyes) were diagnosed with POAG. Besides the standard tests, the ophthalmological assessment included evaluation of OBF (flowmetry) and an individual normal range of intraocular pressure (IOP). The results showed that optic disc drusen are not associated with OBF changes. Concomitant POAG might be suspected in a patient with optic disc drusen whose OBF is significantly decreased and IOP is above the individual normal range. Differentiation of morphofunctional changes in chronic optic neuropathy, which might be due to either glaucomatous optic neuropathy or optic disc drusen, is complicated when actual IOP lies within the average normal range. Ocular blood flow evaluation by means of flowmetry with calculation of an individual normal range of IOP has been demonstrated as a highly effective predictor of concomitant POAG in patients with optic disc drusen.

Characteristics of ocular hemodynamics in ischemic optic neuropathy (ION) outcome and normal tension glaucoma (NTG), the conditions that are difficult to be differentially diagnosed, have been investigated. The study enrolled 32 patients (40 eyes) with ION outcome, 26 patients (46 eyes) with NTG, and 20 patients (32 eyes) with no ocular pathology. Besides the standard ophthalmological examination, color Doppler imaging of ocular vessels, evaluation of ocular blood flow volume and individual normal range of intraocular pressure (flowmetry) were performed in all cases. The results showed that an excess of the actual intraocular pressure (IOP) over the individual normal range was much higher in patients with NTG than in patients with ION (39% and 14.5% correspondingly). It was also found that NTG is associated with a more significant decrease of ocular blood flow volume (30.1% in average) in comparison to ION outcome (11%). In both conditions a decrease in velocity parameters of the blood flow in main ocular vessels was registered, however, ocular hemodynamics changes appeared to be more severe in patients with glaucomatous optic neuropathy. A statistically reliable correlation between volumetric and velocity parameters of ocular blood flow has been discovered.

Retinal morphometric parameters received using confocal scanning laser ophthalmoscopy and optic coherent tomography (OCT) are compared. OCT was performed using Stratus OCT 3000 ("Carl Zeiss Meditec"), and for confocal scanning laser ophthalmoscopy we used Heidelberg retinal tomography HRT 3.0 ("Heidelberg Engineering"). A total of 81 patients (158 eyes) were enrolled into the study: 34 patients (64 eyes) with suspected glaucoma (diagnosis of early open angle glaucoma was proven after ophthalmologic examination) and 47 healthy adults aged from 38 till 72 years old. OCT was found to reveal significant decrease of retinal nerve fiber layer (RNFL) thickness in peripapillary zone in patients with suspected glaucoma as compared with healthy subjects, whereas no significant difference in morphometry of neuroretinal rim and PNFL was found using confocal scanning laser ophthalmoscopy (HRT).

132 patients (188 eyes) with proven optic neuropathy of non-glaucomatous origin were examined using static perimetry, visual evoked potential (flash and pattern types), optic coherent tomography of papilla and thickness of peripapillary nerve fiber layer. Sensitivity/ specificity of methods for identification of optic nerve diseases in acute stage were 92/75%, 92/84%, 90/92% respectively. Combination of these three methods let us identify optic neuropathy in 100% of cases, including latent forms.

In this article the results of practical use of central retinal zone (CRZ) tomography in primary open-angle glaucoma (POAG) measured with RTA (Retinal thickness Analyzer, Talia Technology Ltd., Israel) are presented. 460 patients (790 eyes) aged 45-85 years old were included into the study. Significant decrease of CRZ minimal thickness and perifoveal region thickness (p < 0.05 and p = 0.01 respectively) was revealed in patients with POAG compared with control group. Morphometric data showed correlation with decrease of light sensitivity and visual field defects detected with static perimetry. This fact confirms information value of central retinal morphometric changes for glaucoma diagnosis.

The results of 257 combined, pathogenically oriented operations were analyzed in 181 patients with cataract concurrent with open-angle glaucoma (OAG). A system of pathogenically oriented combined surgical interventions was shown to be highly effective in patients with cataract concurrent with OAG. The proposed procedure for intraoperative determination of the retention of intraocular fluid allows a pathogenically oriented antiglaucomatous component of combined surgery to be chosen in patients with cataract and OAG. Increased visual acuity and stable stabilization of the glaucomatous process were achieved in all cases during a follow-up of less than 3 years.

Thirty-four patients (53 eyes) with suspected optic nerve and retinal diseases were examined. For differential diagnosis, the authors used current studies of the ocular neurosensory apparatus, such as retinal tomography, computer static perimetry, and electrophysiologial techniques, including multifocal electroretinography. The complex use of structural and functional studies of the retina and optic nerve established the valid diagnosis in all difficult clinical cases.

Twenty-six patients (45 eyes) (median age 55 years) with optic disc drusen (ODD) (a study group) and 24 healthy volunteers (47 eyes) (median age 53 years) (a control group) were examined. Nerve fiber layer thinning determined by optic coherence tomography (OCT) was found in 65% of the ODD. In 20% of the patients with ODD, nerve fiber layer thinning, as evidenced by OCT, was observed with the normal field of vision, which suggests the higher sensitivity of a morphometric study of the retinal nerve fiber layer. According to OCT data, 11% of the patients with pathological changes in the field of vision had increased retinal nerve fiber layer thickness in some quadrants or from the mean value. These changes may be associated with the large-sized optic disc in these patients.

The authors proposed a new screening for determining individual tolerant intraocular pressure (TIOP). The investigation covered 107 individuals (167 eyes). All the examinees were divided into three groups. Groups 1 and 3 comprised healthy volunteers without the signs of vascular changes and glaucoma; Group 2 included patients with new-onset glaucoma with uncompensated intraocular pressure (IOP). There was a regression relationship of ocular blood flow (OBF) to the length of the anteroposterior ocular axis (APOA), which showed a high correlation between OBF and APOA. To determine TIOP, the authors proposed the calculation formula: TIOP = P x K/K(n), where P is the tonometric IOP (mm Hg); K is the flowmetric value of OBF (microl/sec); K(n) is the individual normal OBF value (microl/sec) determined by the nomogram developed by the authors, by taking into account the value of APOA (mm). It is suggested that the eye has a certain buffer range of excessive tolerant pressure within which increased ophthalmotonus results in abnormal sequels. The patients with TIOP that is lower than the existing IOP in the absence of glaucoma symptoms should be classified as a risk-group.

This paper presents an analytical survey of the Russian and foreign literature dealing with the current idea on the pathology of a glaucomatous process and methods for the early diagnosis of glaucoma. It gives data on the impact of intraocular pressure, central corneal thickness and ocular biomechanical properties on the pathogenesis of primary open-angle and normotensive glaucoma. The results of electrophysiological, psychophysiological, ultrasound, and morphometric studies were assessed in the diagnosis of primary open-angle glaucoma.

The paper describes the first experience in using multifocal electroretinography (mfERG) in patients with antiphospholipid syndrome (APS). In the latter, thrombogenesis is mosaic in most cases so the techniques providing a spatial imaging of the pathological process is of interest in the examination of patients with this disease. These techniques include mfERG. The quadrant mfERG analysis that reveals pathological changes in relation to the vascular involvement area is of the greatest informative value in patients with APS-associated retinal vascular occlusions.

Based on the analysis of the data of a multifocal electroretinography FOK response and the retinal thickness in 38 patients with suspected glaucoma, the paper shows the inhibition of the external retinal biopotential and the lower retinal thickness in the posterior ocular pole. There is a correlation of these changes with light sensitivity alterations, as evidenced by quadrant analysis. It is stressed that monitoring of patients with suspected glaucoma must comprise a morphofunctional assessment using the current techniques.

The paper considers the possibilities of using multifocal electroretinography (mfERG) to examine patients with primary glaucoma. Forty-seven patients underwent mfERG that established that as the disease progressed, there were reductions in the mfERG wave amplitude, when the first flash response, and in biopotential density, when the quadrant analysis was made. Biopotential changes in glaucoma can be analyzed in relation to the first flash response and a pattern response. Monitoring of changes in primary glaucoma may use mfERG.

Morphometric studies using a laser retinal thickness showed great differences in the impact of hydromonitoring phacofragmentation and ultrasound phacoemulsification on the thickness of the central retinal region. Unlike ultrasound phacoemulsification, hydromonitoring phacofragmentation caused no transient increase in the thickness of the central retinal area. The performed studies revealed no correlation between the equivalent time of ultrasound and ultrasound phacoemulsification and the changes in the thickness of the central retinal region and fovea.

The purpose of the study was to assess the results of photodynamic therapy (PDT) for subretinal neovascular membranes (SNM) in age-related macular degeneration (ARMD), by using the Russian drug Photosens. According to the treatment performed, all the patients were divided into 2 groups: 1) 18 patients with the neovascular form of ARMD who received a course of PDT; 2) 14 patients with the same form who had drug therapy. Photosens (aluminum phthalocyanine) was intravenously injected in a dose of 0.05 mg/kg. The irradiation conditions were as follows: a session was carried out, using a laser at a wavelength of 675 nm, in an exposure light dose of 120 J/cm2. The number of sessions ranged from 3 to 5 a week, depending on the clinical picture of SNM. The total light dose was not greater than 500 J/ cm2. PDT showed a higher efficiency, as compared to drug therapy. PDT using Photosens increases and stabilizes visual acuity in 50% of cases, improves retinal functional activity (an increase in the mean value of a b-wave amplitude), and causes positive changes in the morphometric values of the mean neuroepithelial thickness above SNM and in the foveola.

The efficiency of photodynamic therapy (PDT) versus drug therapy was evaluated in patients with subretinal neovascular membranes (SNM) in complicated myopia (CM). Photosens (aluminum phthalocyanine) was intravenously injected in a dose of 0.05 mg/kg. The irradiation conditions were as follows: a session was carried out, using a laser at a wavelength of 675 nm, in an exposure light dose of 120 J/cm2. The number of sessions ranged from 3 to 5 a week, depending on the clinical picture of SNM. The total light dose was not greater than 500 J/cm2. Twelve months after drug therapy and a course of PDT, reduced visual acuity was observed in 50% and only 20.8% of cases, respectively. Stabilization or increase of visual functions occurred in the remaining patients receiving a course of PDT.

The authors studied the effectiveness of photodynamic therapy (PDT) with Photosence, a Russian photosensitizer, in treatment of chorioid neovascularization (CNV) in cases of age-related macular degeneration (ARMD) and pathological myopia (PM). The subjects were 73 patients with CNV suffering from ARMD and PM. The efficiency of PDT and complex conservative therapy was compared using vision acuity measurement, retinal morphometry, and fluorescent eye ground angiography (FEGA), performed before treatment, immediately after treatment, and 1, 3, 6, and 12 months later. The study showed that PDT in patients with CNV, ARMD and PM was more efficient than pharmacotherapy. Vision acuity improved or stabilized, and the parameters of retinal morphometry and FEGA improved as well. The results of the study evidence high efficiency of PDT with Photosence in treatment of CNV with ARMD and PM.

The paper presents the comparative data of retinal tomography in the presence of choroidal neovascularization. In all patients, life-time morphometry of a 6x6-mm central retinal area (at 20 degrees from the point of fixation) was made on a retinal thickness analyzer (Talia, Israel). During the study, the authors analyzed the most significant indices: mean retinal posterior pole thickness; mean retinal paracentral region thickness; mean retinal central region thickness; mean neuroepithelial thickness above the subretinal neovascular membrane (SNM). Statistical analysis showed that the increase in neuroepithelial thickness was directly related to that in the intensity of SNM fluorescence. The mean neuroepithelial thickness above SNM, intra- and subretinal hemorrhages, intraretinal microcysts in patients with age-related macular degeneration and the presence and extent of thinning and fibrotic area permitted evaluation of the magnitude of activity and presumptively the duration of choroidal neovascularization.

Retinal functional activity was studied in 11 patients with different stages of senile macular degeneration (SMD), by computer-aided perimetry (Pericom) and multifocal electroretinography (EP-1000 Multifocal Tomey). The scotomas of a quadrant of the visual field were analyzed. Both methods were shown to complement each other. In the classical dry form of SMD, less pronounced changes in the objective perimetry may correlate with more pronounced changes in the subjective perimetry; in its moist form, changes may be reversible. The combined use of two methods can increase the level of monitoring retinal diseases.

Eighty volunteer computer operators were examined experimentally under the conditions of working with different-type video monitors, i.e. electron-beam (EB), liquid-crystal (LC), including different visual loads (typing, computer games, and gaze fixation). Experiments lasted for as long as 6 hours. The absolute accommodation volume (AAV), relative accommodation reserve (RAR) and ergograms were comparatively evaluated. A lower AAV was registered in all types of visual loads under the conditions of using different-type monitors, and it made up 0.27-1.08 diopters. A maximum reduction of AAV was detected for gaze fixation and while working with liquid-crystal monitors. The RAR reduction ranged from 0.31 to 0.63 diopters. A maximum RAR reduction was noted for gaze fixation and while using the electronic-beam monitors. The nature of changed ergography curves occurred within the interval between I and IIb types of ergograms. In case of typing, the ergogram deviations were registered to a greater extent for the liquid-crystal monitors. The value of deviations for computer games was bigger, at the experiment end, for EB rather than for LC.

Due to a number of reasons, the traditional methods of cataract extraction, i.e. through 8-12 mm limbic incisions, are still widely used in the clinical practice. A frequent occurrence of a high postoperative astigmatism, even if the operation is successful, is the main shortcoming of different variations of the traditional method of cataract extraction. Possibilities of how to neutralize the induced "suture-like" corneal astigmatism were investigated in this study by using two methods: A. a modified technique of applying a continuous corneal Pirs' suture with elements of an accentuated impact in the projection of the horizontal meridian. B. Meridian keratorraphia--application, in the cornea, of an additional compensatory suture in the projection of the horizontal meridian. Studies were made in two groups of patients after extracapsular cataract extraction (ECE) with intraocular lens (IOL) implantation--a total of 30 patients, 30 eyes. The main group was divided into two subgroups--A and B--(10 patients and 10 eye in each) in accordance with a used method of compensating the induced astigmatism. 10 patients were in the control group. A comparative evaluation of changes of a degree of the original astigmatism, which occurred under the influence of the sealing suture, showed that the parameters of induced astigmatism in the control group essentially and reliably (p < 0.001) exceeded the similar parameters registered in both subgroups of the main group; finally, the efficiency of method B in respect to neutralizing the "suture" astigmatism out did the possibilities of method A (p < 0.01).