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Currently, there is a significant shortage of donor materials for replacing corneal tissue that is why it is relevant to create xenomaterials, which are able to replace a donor cornea with various types of keratoplasty. “Corneoplast” is a new medical device, which is a devitalized, fixed by the method of double crosslinking (dehydrothermic + UV), pork cornea.Purpose: to assess the biocompatibility and ability to integrate with the recipient cornea of implants based on the xenomaterial “Corneoplast”.Materials and methods. The experiment was based on biomicroscopy examination, high-resolution optical coherence tomography and histological examination of the experimental rabbits’ corneas (group I–IV: total of 8 eyes were examined), where keratoplasty was performed with the “Corneoplast” material.Results. High biocompatibility and ability to integrate with the recipient’s cornea were observed in all types of keratoplasty: penetrating, superficial lamellar and intralamellar keratoplasty. On the next day, the implant was transparent with slight swelling of the recipient’s corneal stroma. A week later, the slight swelling of implant was recorded without cornea edema. Its transparency decreased. The recipient’s cornea was reactive. A month later, the moderate neovascularization was noted towards the sutures. After 6 months, the recipient’s cornea was clear, transparent. The implant was translucent and neovascularization was absent. The entire surface of cornea and implant was epithelialized. On the series of optical coherent tomograms, a normal thickness of the epithelium continuous layer was determined in 6 months after the surgery. The complete integration of material with the recipient’s cornea was noted. The layered structure characteristic of corneal tissue was preserved. The cornea retained a layered structure and the endothelium was preserved. On histological examination, there were no differences in the intact cornea and implanted material.Conclusion. The “Corneoplast” material is sufficiently biocompatible and capable of integration with the recipient’s cornea in an animal experiment. This allows, at a certain stage of preclinical trials completion, to use it for replacing corneal tissue in penetrating keratoplasty, intralamellar and superficial anterior layer-by-layer implantations and to cover purulent corneal ulcers of various depths.

PURPOSE. To conduct a comparative study of the balance of macro- and microelements in scleral biopsy samples taken from patients with various clinical forms of glaucoma.METHODS. The content of macro- and microelements was analyzed in scleral biopsy samples of 16 patients with primary open-angle glaucoma (POAG), 13 patients with normal tension glaucoma (NTG) and 15 patients with pseudoexfoliative glaucoma (PEG). The mean age of the patients was 79.5±2.5 years. For control, fragments of the sclera of 14 cadaveric eyes without a history of glaucoma were used. Concentration of macroelements — K, Mg, Ca, Fe — was determined by inductively coupled plasma atomic emission spectrometry, the level of microelements — Zn, Cu, Al, Mn — by inductively coupled plasma mass spectrometry.RESULTS. A statistically significant shift in the balance of Cu/Zn compared with controls was found in all forms of glaucoma: NTG (p=0.008), PEG (p=0.006), POAG (p=0.03); while no differences between NTG and POAG in this indicator were detected (p=0.609), with PEG the difference was significant (p=0.0001). The Cu/Fe ratio in the scleral samples of glaucomatous eyes also significantly differed from controls in both NTG (p=0.009) and PEG (p=0.006), as well as in POAG (p=0.006). This parameter in patients with POAG significantly differed from the corresponding parameter in the groups with NTG (p=0.0001) and PEG (p=0.016). A shift in the balance of Mn/Cu compared with controls was detected only in the sclera of patients with NTG (p=0.0064), there were no corresponding differences with controls in PEG (p=0.157) and POAG (p=0.773), but a significant difference was found between NTG and POAG groups (p=0.0001). The balance of Mn/Fe in comparison with the control group was disturbed in all forms of glaucoma: NTG (p=0.0066), PEG (p=0.00034), POAG (p=0.0027). At the same time, in patients with NTG and PEG, the balance of Mn/Fe differed significantly from this indicator in POAG (p=0.078 and p=0.0485, respectively). The most pronounced imbalance of Mg/Ca compared with controls was found in the sclera of patients with PEG (p=0.01) and POAG (p=0.0254).CONCLUSION. In all studied forms of glaucoma, disturbances in the ratios of Cu/Zn, Cu/Fe, Mn/Cu, Mn/Fe and Mg/Ca of varying severity in the sclera were revealed in comparison with the sclera of eyes without glaucoma. Differences in the indicated ratios between NTG, POAG and PEG have also been established, which may define the features in the pathogenesis and clinical course of these forms of glaucomatous lesions.

Glaucoma is a socially significant disease and ranks first among the causes of visual impairment and blindness. Glaucoma is a chronic disease with progressive course, and the entire treatment and diagnostic process is associated with the need for constant monitoring of the structural and functional components of the visual system to assess the progression of glaucomatous optic neuropathy. With adequately chosen treatment tactics, it is possible to stabilize the glaucomatous process and successfully reverse the structural and functional changes thanks to the links between functional defects of the visual fields and topographic damage in the optic nerve with the stage of the disease. This statement emphasizes the need to choose the correct treatment tactics, as well as to closely monitor the structural and functional characteristics of patients with glaucoma. In this regard, the issue of studying the safety and effectiveness of various glaucoma surgeries depending on observation time remains relevant.

Purpose. To evaluate the efficacy and safety of femtolaser-assisted phacoemulsification in glaucomatous eyes in the long-term follow-up. Materials and methods. A retrospective analysis of the results of the surgical treatment of patients with combined cataract and glaucoma pathology was analyzed. The patients were divided into groups depending on the method of surgical intervention: 1) phacoemulsification with femtolaser support (26 eyes, 23 patients); 2) phacoemulsification (36 eyes, 30 patients); Results. Before surgery, there were no statistically significant differences in IOP and corneal hysteresis (СН) between groups 1 and 2. The mean values of IOP cc, IOP g and СН of group 1 before surgery were 22.7±6.1 mm Hg, 20.9±6.9 mm Hg, 8.5±1.6 mm Hg; 2 group – 22.9±8.7 mm Hg, 21.6±8.9 mm Hg, 8.9±1.6 mm Hg respectively. Average values of IOP cc, IOP g and CН 5 years after the surgical treatment in group 1 were 15.3±1.2 mm Hg, 14.4±3.4 mm Hg, 9.6±4.2 mm Hg; in group 2 – 18.0±4.2 mm Hg, 16.1±4.2 mm Hg, 8.8±2.2 mm Hg respectively. In both groups, stabilization of IOP and CH indices was noted, which remained throughout the entire observation period, which shows the normalization of the biomechanical properties of the corneoscleral membrane of the eye in the long-term postoperative period. Conclusion. Femtolaser accompaniment of phacoemulsification is an effective and safe method of cataract surgery for combined pathology. Key words: femtolaser, cataract, glaucoma, phacoemulsification.

Objectives: To present and validate the novel grading system for objective classification of corectopia.Subjects and Methods: We evaluated 28 eyes of 28 patients with or without corectopia and validated the grading and classification system for corectopia according to three major criteria: (i) direction, (ii) extent, and (iii) alteration of mydriasis. Intraclass correlation coefficient (ICC) and inter-rater agreement between 7 inexperienced and 1 experienced ophthalmologist against a golden standard (GS) were calculated.Results: The ICC for the 7 inexperienced ophthalmologists regarding the grading of direction and centration of the pupil was 0.83 (95% confidence interval (CI), 0.74 to 0.90; p

To investigate the long-term effectiveness of non-penetrating deep sclerectomy (NPDS) with xenogenically derived cancellous bone collagen glaucoma implant (XCB-CGI) implantation in patients with primary open-angle glaucoma (POAG). Retrospective chart review of patients with POAG stages 2 and 3 was treated with NPDS and XCB-CGI. Follow-up was at 6 months, 1, 2, 3, 4 and 5 years after surgery. Main outcomes were intraocular pressure (IOP) and medication burden. Secondary outcomes were visual acuity, corneal hysteresis (CH), visual field (VF) and optical coherence tomography (OCT) parameter analysis. Among 71 patients (71 eyes), the mean age was 72.7 ± 9.8. Average initial IOP was 27.7 ± 7.9 and average initial med load was 2.36 ± 0.99. At 6 months, 1, 2, 3, 4 and 5 years, the average IOP was 14.9 ± 3.3 mm Hg (46.2% reduction), 15.3 ± 4.0 mm Hg (44.7% reduction), 14.2 ± 3.8 mm Hg (48.7% reduction), 15.2 ± 3.3 mm Hg (45.0% reduction), 15.5 ± 3.3 mm Hg (44.0% reduction) and 14.2 ± 2.8 mm Hg (48.7% reduction), respectively. In 5 years, the success rate was 34% and 67%, without, and with medications (1.8 ± 0.8 meds required), respectively. Visual acuity was not significantly different (P > .05) at all follow-up visits from baseline. Mean CH increased by 2.1 ± 0.8 (P = .05). No glaucomatous deterioration of the VF and OCT parameters was detected in 56 eyes at the 5-year follow-up. NPDS with XCB-CGI implantation is an effective procedure to normalize the level of IOP, stabilize glaucomatous changes and decrease the number of meds needed for glaucoma control.

The results of studies of mass transfer through a polyamide composite reverse-osmosis membrane in the demineralization of dilute solutions of six strong electrolytes are summarized. The relation of the electrolyte concentration at the surface of the reverse-osmosis membrane, at which its true selectivity tends to zero, to the specific water flux and the sum of the hydration numbers of the cations and anions of this electrolyte has been revealed. It has been shown that at a low salinity of the feed solution, the product of the molar electrolyte flux and the sum of the hydration numbers of its cations and anions for the test membrane is almost independent of the electrolyte type. An analysis of the dependence of the solute flux on the transmembrane pressure, concentration, and temperature in the electrolyte concentration range of 0.2 to 20 mol/m3 in the feed solution, as well as the experimentally determined activation energy of the NaCl flux, has led to the conclusion that there is an additive component of the electrolyte flux, whose contribution to the total flux is insignificant at high concentrations and becomes determining at concentrations below 2–5 mol/m3.

Aim The aim of this study is the development and evaluation of clinical significance methodology for determining mech­anical stress (MS) and elasticity of the cornea comparable to its topographic settings. Materials and methods Combining the data of optical pachymeter, keratotopography, and pneumotonometry through our special software allows us to get Lokolink MS distribution in the cornea in the form of maps, which we propose to call keratotensotopogram (KTT). Results Normal KTT has the form of concentric, uniform, and symmetrical zones. In keratoconus (KC), the corneal center is more tense than peripheral part of cornea. The focus zone of KC may coincide with the region of maximum MS or may be out of this area. In the process of vacuum-compression test, the reaction of profile of the cornea was markedly different in patients with healthy corneas and in patients with KC. In all cases of healthy cornea, the curvature increased in the center. In KC, the cornea became more flat in the center under high intraocular pressure (in 100% of cases). Conclusion The KTT ineyes with the cornea without pathology differs from KTT in the different cases of KC. The KTT can be used for the diagnosis and prediction of cornea's state to perform the plan of UV irradiation areas for corneal collagen cross-linking. How to cite this article Anisimov SI, Anisimova SY, Mistryukov AS, Anisimova NS. Technology of the Local Cross-linking (Part 1): Keratotensotopography and Vacuum-compression Topographic Test—New Diagnostic Possibilities for Studying the Local Biomechanical Properties of Cornea. Int J Kerat Ect Cor Dis 2017;6(1):14-16.

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.Кросслинкинг роговицы (КЛР) — это операция, направленная на стабилизацию прогрессии кератэктазии за счет образования новых ковалентных связей в структуре коллагеновых волокон стромальной части роговицы и экстрацеллюлярном матриксе под воздействием ультрафиолетового излучения (УФ, 370 нм) и фотосенсибилизатора (рибофлавина). Согласно традиционному протоколу, рекомендуемая толщина роговицы после удаления эпителия должна составлять не менее 400 мкм, так как ее меньшая толщина может привести к повреждению эндотелиальных клеток. Однако при прогрессивном течении кератоконуса толщина роговицы нередко достигает пороговых значений либо имеет размер менее 400 мкм, что ограничивает применение КЛР у данных пациентов. Настоящая работа посвящена обзору различных протоколов и методов проведения КЛР при тонких роговицах с описанием их преимуществ и недостатков. В настоящее время исследования модифицированных протоколов КЛР по-прежнему ограничены методологией и тем, что в них участвует небольшое количество пациентов. Таким образом, для подтверждения безопасности и эффективности модифицированных протоколов кросслинкинга тонких роговиц, а также для выявления наиболее эффективного протокола необходимо проведение сравнительных рандомизированных контролируемых исследований с долгосрочным наблюдением.

Studying clinical and functional outcomes of femtosecond laser-assisted posterior lamellar keratoplasty is an actual problem in endothelial keratoplasty.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).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.Comparative analysis did not reveal statistically significant differences in AL, CL, and CCT values between the groups (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.Зучение клинико-функциональных результатов фемтосекундной лазерной задней послойной кератопластики (ФЛ-ЗПК) является актуальной проблемой эндотелиальной кератопластики.Провести сравнительный анализ данных оптической плотности роговицы у пациентов после ФЛ-ЗПК и задней автоматизированной послойной кератопластики с использованием микрокератома (ЗАПК).В проспективное одноцентровое рандомизированное исследование включено 37 пациентов (37 глаз) с эндотелиальной дистрофией роговицы Фукса и сопутствующей катарактой. В первой группе 20 пациентам (20 глаз), проведена ФЛ-ЗПК и факоэмульсификация (ФЭ) с имплантацией интраокулярной линзы (ИОЛ). В группе контроля 17 пациентам (17 глаз) выполнена ЗАПК одномоментно с ФЭ и имплантацией ИОЛ. В ходе исследования применяли: оптическую когерентную томографию переднего отрезка глаза, эндотелиальную микроскопию и денситометрию. Проводили оценку общей оптической плотности роговицы и различных ее слоев (передний слой, центральный слой, задний слой и зона интерфейса) в зонах 0—2 и 2—6 мм. Максимальный срок наблюдения составил 1 год.Сравнительный анализ не выявил статистически значимых различий параметров общей оптической плотности роговицы, денситометрии передних и центральных слоев роговицы между группами (Показатели общей оптической плотности роговицы, денситометрии передних и задних слоев роговицы были сопоставимы между группами с двумя исследуемыми хирургическими техниками. Отмечено преимущество техники ЗАПК на всех сроках наблюдения по параметрам НКОЗ, МКОЗ и ПЭК.

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.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.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.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.Цель данной работы - сравнительная оценка клинических результатов во время и после проведения факоэмульсификации (ФЭ) с фемтолазерным сопровождением (ФЛС) и ФЭ по стандартному методу у пациентов с осложненной катарактой в сочетании с сублюксацией хрусталика I-II степени, псевдоэксфолиативным синдромом и глаукомой после ранее проведенной гипотензивной операции. Материал и методы. Всего исследовано 197 пациентов (245 глаз) с осложненной катарактой. Возраст больных составил от 32 до 85 лет (в среднем 58,5 года). В зависимости от использованного метода ФЭ пациенты были разделены на 2 группы: 1-ю группу (основную) составили 105 человек (120 глаз), которым была выполнена ФЭ с ФЛС; 2-ю группу (сравнения) - 92 пациента (125 глаз) после ФЭ, проведенной по стандартному методу. Через 1, 3, 7 дней и 1 мес после операции оценивали субъективные и объективные показатели структурно-функционального состояния органа зрения. Результаты. По данным ультразвуковой биомикроскопии, в группе ФЭ с ФЛС интраокулярная линза занимала центральное положение в капсульном мешке. На протяжении всего периода наблюдения все показатели оставались стабильными, не отмечены случаи смещения или девиации хрусталика. Во 2-й группе (стандартный метод) отмечалась большая лабильность показателей на протяжении всего периода наблюдения. Заключение. Сравнительный анализ обоих методов ФЭ выявил ряд существенных преимуществ ФЭ с ФЛС. Использование данного метода является важным моментом в лечении осложненной катаракты. ФЭ с ФЛС позволяет сократить время использования ультразвука, произвести точный капсулорексис заданных размеров, снизить процент операционных и послеоперационных осложнений и улучшить рефракционный результат артифакии у пациентов с осложненной катарактой.

A system for ultrafiltration of viscous solutions for biological and medical applications was developed based on track membranes. The system includes a filtering cell and a set of calibrated removable filters with pores of different diameter. The advantages of this system are strictly controllable filtration parameters, virtually 100% selectivity with respect to object size, and high performance. Filtration modes were studied; feasibility of obtaining filtrates of cellulose derivatives with given parameters was demonstrated. A developed system of metrological monitoring makes it possible to adapt this filtration technology to any non-aggressive highly viscous polymer solutions. Application of track membranes with given characteristics is a promising approach to medical engineering and biological research.

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.

The non‐linear analysis of the plane shock wave stability in media with arbitrary equation of state has been carried out in a systematic way. The one and multi‐dimensional computations have been conducted in the inviscid and viscous formulations. The real and properly constructed model equations of state have been used. The behavior of shocks in the regions of their ambiguous representation overlapping the Hugoniot segments that meet the linear criteria of the shock wave instability has been studied. The evolution of shock waves being neutrally stable in keeping with the results of the linear analysis has been also simulated. The results obtained indicate basic distinctions from the linear theory predictions.

The mathematical model of interaction the energy meridian of human organism for optimization of influence during doing extremely-high frequencies therapy is presented. This mathematical model made with using mathematical methods of automatic control theory

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.

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.

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.

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.

A new method for the quantitative estimation of the vitreous body colloidal state has been suggested. For realization of the method a fragment of the vitreous body and an equal volume of water are dried out, and the drying time is registered. The higher is the ratio between the drying time of the vitreous body fragment and water, the higher is the density of the vitreous body gel. The drying out of the vitreous body fragment and water on the analytical balance cups permits the registration of the drying out process in the time course. Thus some additional parameters are obtained that characterize the object studied more completely. The method can be used in experimental and clinical investigations of the vitreous body and other biological liquids.

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.

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.

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.

A new method for the quantitative estimation of the vitreous body colloidal state has been suggested. For realization of the method a fragment of the vitreous body and an equal volume of water are dried out, and the drying time is registered. The higher is the ratio between the drying time of the vitreous body fragment and water, the higher is the density of the vitreous body gel. The drying out of the vitreous body fragment and water on the analytical balance cups permits the registration of the drying out process in the time course. Thus some additional parameters are obtained that characterize the object studied more completely. The method can be used in experimental and clinical investigations of the vitreous body and other biological liquids.

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.