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This article reviews pseudo-accommodative intraocular lenses (IOLs), providing an analysis of the terminology used in this field of ophthalmology and describing the design of modern IOLs, the technological features used to achieve pseudo-accommodation that meets the needs of patients, particularly the new extended depth of focus (EDOF) IOL technology. The article presents the main types of extended depth of focus IOLs, their description, advantages and disadvantages, as well as comparison with multifocal and monofocal IOLs based on clinical studies conducted in different countries.

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Studying clinical and functional outcomes of femtosecond laser-assisted posterior lamellar keratoplasty is an actual problem in endothelial keratoplasty. PURPOSE: To compare the values of corneal densitometry (CD) as measured by the Scheimpflug camera (Pentacam) following femtosecond laser-assisted Descemet stripping endothelial keratoplasty (DSEK) vs microkeratome-assisted Descemet Stripping Automated Endothelial Keratoplasty (DSAEK). MATERIAL AND METHODS: The prospective single center randomized study included 37 eyes of 37 patients with Fuchs endothelial dystrophy and cataract. 20 patients underwent cataract phacoemulsification combined with Femto-DSEK; 17 patients of the control group underwent cataract phacoemulsification combined with DSAEK. Outcome measurements included optical coherence tomography of the anterior segment of the eye, endothelial microscopy and densitometry. Optical density of the cornea and its various layers: anterior layer (AL), central layer (CL), posterior layer (PL) and interface zone was assessed in the 0-2 and 2-6 mm zones. The follow-up period lasted 1 year. RESULTS: Comparative analysis did not reveal statistically significant differences in AL, CL, and CCT values between the groups (p>0.05). In the Femto-DSEK group, densitometry indices of the posterior layers of the cornea and the interface zone were significantly higher than in the DSAEK group (p<0.05). Postoperative uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) differed significantly throughout all follow-up period with DSAEK group having better results (p<0.05). Endothelial cell density (ECD) at 12 months was higher in the Femto-DSEK group compared with the DSAEK group (65.7±7.7% and 58.5±8.1%, p=0.02, respectively). CONCLUSION: After one year, corneal density values (AL, CL, PL) and CCT were comparable between the groups. UCVA, BSCVA and ECD were significantly better after DSAEK.

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Corneal collagen cross-linking (CXL) is a procedure that aims to halt the progression of corneal ectasia in keratoconic eyes. It is achieved by inducing cross-links in the corneal stroma and extracellular matrix by exposing it to ultraviolet-A (370 nm) irradiation while it is filled with photosensitizer (riboflavin). According to the conventional protocol, the recommended de-epithelialized corneal thickness should be higher than 400 µm in order to avoid radiation damage to the corneal endothelium. However, in progressive keratoconus, corneal thickness is often close to or lower than this threshold of 400 µm, which limits the application of cross-linking for these patients. The present article reviews the different protocols of cross-linking for thin corneas, their advantages and disadvantages. At present, clinical research on modified cross-linking protocols is still limited due to the methodology and a low number of patients involved. Thus, comparative randomized controlled studies with long-term follow-up are necessary to confirm the safety and effectiveness of several CXL protocols and identify the most efficient one.

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AIM: to perform comparative evaluation of intra- and postoperative clinical RESULTS in patients with complicated cataracts (grade I-II lens subluxation, pseudoexfoliation syndrome, or surgically treated glaucoma) undergoing either standard or femtosecond laser-assisted phacoemulsification. MATERIAL AND METHODS: A total of 197 patients (245 eyes) aged 32-85 years (58.5 years on average) with complicated cataracts were divided into two groups by the technique used for phacoemulsification. Group 1 (main group, 120 eyes of 105 patients) underwent femtosecond laser-assisted phacoemulsification. Group 2 (controls, 125 eyes of 92 patients) received standard procedures. Subjective and objective measures of ocular structure and function were evaluated in 1, 3, and 7 days and 1 month after the surgery. RESULTS: In the femtosecond laser-assisted group, all lenses were well-centered in the capsular bag as documented by ultrasound biomicroscopy. During the whole follow-up period the studied parameters were stable. No dislocations occurred. In group 2 (standard phaco), all parameters demonstrated high changeability over the follow-up period. CONCLUSION: The improved technique of femtosecond laser-assisted phacoemulsification offers many advantages to surgical management of complicated cataracts. Not only does it allow to reduce ultrasound time, but also to perform precise capsulorhexis with preset parameters, decrease intra- and postoperative complications rates, and improve refraction outcomes in such patients.

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Effect of sunlight transformed by luminophore-containing materials on cell viability and functional state of the retina was assessed using the photodamage model. Exposure to the luminescent component of light improved viability of NIH 3T3 cells and promoted recovery of electric activity in rabbit retina after photodamage.

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Three hundred and fifty-four LASIK surgeries made in myopia were analyzed. The share of epithelium-related complications made up 3.1%. Persistent irregular astigmatism and impaired visual acuity with correction shaped up in 5 cases. All patients underwent laser photoablation of the epithelium in the phototherapeutic keratectomy (PTK) regimen by using an original technique. The "Keracor 217 C" laser (2 mm spot, 120 mlJ./cm2 energy and 25 Hz frequency) was applied. The treatment resulted in a reliably improved visual acuity and normalized anterior corneal surface.

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A total of 4810 laser keratomilase surgeries (LASIK) in myopia and hypermetropia were analyzed. The spherical equivalent of clinical refraction in myopia amounted to -6.56 +/- 1.34 diopters, in hypermetropia it amounted to +3.97 +/- 1.74 diopters. The refraction parameters in myopia ranged from 1.5 diopters to 12.0 diopters; in case of astigmatism they ranged from 0.5 diopters to 2.75 diopters, and in hypermetropia they varied from 1.5 to 6.25 diopters. The age of patients ranged from 18.5 to 52; there were 49.3% male patients and 50.7% female patients. The observation period was up to 2 years. The lamellar corneal incision was implemented by three types of microkeratomes: "Hansatome" (Germany), "Moria" (France) and "Nidek" (Japan). Photoablation was carried out by Keracor Techlas 217 (Germany) of the "flying dot" scanning type and by "Profil 500" (Russia). The primary DLK reaction of the dystrophic nature amounted, during the first year of using the method, to 1:75 cases, during the second year it was 1:350 cases. The share of secondary DLK manifestations ranged from 0.1 to 17% with regard for a type of complications. DLK can be characterized by various forms, phases and stages. The reaction can be primary (early) and secondary (delayed). Basically, it is a universal inflammatory response of keratocytes to a prolonged malfunction of lamellar flap due to disadaptation. It is described as a complication of the lamellar surgery as a whole and is, most probably, a response to the sutureless surgery. There are factors, which diminish the frequency of such complication. A new working classification of the DLK response is presented. A new clinical classification of DLK and DLK-like conditions in the corneal lamellar surgery is offered. Finally, notion "lamellar malfunction" is offered for a comprehensive usage in refraction surgery.

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A general phenomenological theory of hydrodynamic waves in regions with smooth loss of convexity of isentropes is developed, based on the fact that for most media these regions in the p-V plane are anomalously small. Accordingly the waves are usually weak and can be described in the manner analogous to that for weak shock waves of compression. The corresponding generalized Burgers equation is derived and analyzed. The exact solution of the equation for steady shock waves of rarefaction is obtained and discussed.

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The parameters of the ophthalmic artery bed of a patient were reconstructed from X-ray tomography data. Based on these parameters and additional information on the morphology and mode of blood circulation in the choroid and retinal artery, a mathematical model of blood circulation in the eye, oxygen transfer in blood stream, and oxygen consumption in the enzymic reaction was constructed. Using the model, the steady-state oxygen distribution in the vicinity of the bed is shown and the kinetic parameters of the enzymic reaction of oxygen consumption were estimated.

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The investigation of 26 acromegalic patients long after irradiation of the pituitary body with a proton beam showed clinical and hormonal improvement in 38% of the patients, clinical improvement without complete growth hormone normalization in 46%, and the absence of any effect in 15%. The latter was mainly a result of partial irradiation of pituitary adenoma. Some patients after proton irradiation demonstrated signs of adenohypophyseal functional insufficiency, more marked in patients with a decreased level of Gy (over 5 ng/ml). A conclusion is that proton beam therapy is effective (provided all criteria for patients' eligibility are observed) and can be used as an independent method for the treatment of acromegalic patients.

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Computerized tomography has been used to examine 10 patients with cranial injuries aftereffects presenting as optic nerve atrophies (Group 1), 24 patients with nontraumatic optic nerve atrophies (Group 2), and 89 subjects without optic nerve abnormalities. Density asymmetry in the projection of the optic nerve canal cranial openings has been the computerized tomography sign that indicated the involvement of the optic nerve in Group 1 patients. Increased pneumatization of the main bone sinus has been detected 2 times more frequently in Group 2 patients.

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Comprehensive examinations of the optic nerve anatomy and function in atrophies of various origins have revealed a correlation between computerized tomography data and clinical and functional characteristics in 67 patients. A staged pattern of the development of anatomic shifts corresponding to CT data on the changes in the optic nerve diameter and density in accord with the length of the disease has been determined, as well as a relationship between these shifts and the patients' age and the degree of the calcification of the internal carotid arterial walls. CT signs of the optic nerve atrophy are related to functional disorders. Impaired circulation in the internal carotid arteries augments the atrophic process in the optic nerve. These data may be useful for the selection of a method for the management of optic nerve atrophy and for assessment of the treatment efficacy.

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Method of computer tomography with variable radiant energy is described. It permits to compensate the distortions in computer-tomographic sections in case of change in tube operating conditions and in visualization of information about tissue composition within the sectional limits. The developed method increases the efficacy of computer tomography.

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The paper is devoted to analysis of the results of CT in 1000 patients examined in the Multibranch Research and Technology Complex "Eye Microsurgery". The specific feature of CT in this institution is that 52% of all investigations of ophthalmological patients fall to the share of eyeball abnormality and 40%--to a study of the other parts of the organ of vision. CT indications are extended for low tension glaucoma, complicated high myopia, and for monitoring the position of microsurgical implants. The use of CT in such a highly specialized medical institution as the MRTC "Eye Microsurgery" is considered indispensable.

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Reducing the scanning time and the X-ray tube anode current to 80-100 mA is the main way of reducing the radiation dose without noticeably lowering the tomogram image quality in examination of the eye area using the USA QUAD-1 X-ray computer tomograph of the fourth generation. The optimum tube voltage is 140 kW. Narrowing the collimator slit and reducing the number of sections can also lower the total radiation dose, but these measures are less universal for they are determined by clinical situation.

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The adhesive activity of several polymers as regard to vitreous body (VB) was examined by drying out the vitreous body on the surface of the materials under study. 3 types of polymers were compared with glass (silicon, polyurethan, polymethylmetacrilate). According to the reduction in adhesive activity as regard to VB the substances were ranged from silicon to glass. The authors believe that the mechanism of VB adhesion to polymers is linked to the absorption of gialuronic acid on their surface, which is part of VB. The above method is suggested for the selection of polymers used in the manufacturing of intraocular lenses.

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