Search

Objective: To determine clinical value of the use of the upper limit of individual normal range of intraocular pressure (IOP) in glaucoma diagnosing., Material and Methods: The study enrolled 229 conditionally healthy participants (229 eyes) with no ocular complaints after a basic ophthalmic assessment. Ocular blood flow and IOP were measured with Ocular Blood Flow Analyzer (Paradigm Medical Industries). An original formula was further used for calculation of the upper limit of normal range of IOP. All patients were divided into two groups depending on whether or not their IOP fell within the statistically normal range, i.e. was less than 21 mmHg. Thus, group 1 included 193 patients (193 eyes) with IOP from 6.7 to 21.0 mmHg, group 2 -36 patients (36 eyes) with IOP from 21.7 to 30.8 mmHg. Glaucoma diagnosis was made from automated perimetry (Humphrey Visual Field Analyzer) and retinal tomography (HRT3, Cirrus HD-OCT) findings., Results: In group 1, the IOP was found to exceed the upper limit of individual normal range in 38 eyes, thus indicating the probability of glaucoma; of them, in 23 patients (60.5%) the diagnosis was confirmed by further examinations. In the rest 155 eyes from group 1 the IOP matched the individual normal range; of them, glaucoma was ruled out in 154 eyes (99.35%). In group 2, a risk of glaucoma was determined in 27 eyes, of which 24 (88.9%) were further diagnosed. In 9 eyes the IOP exceeded the statistically normal values and yet was within the individual normal range. In none of those 9 cases glaucoma was found., Conclusion: The upper limit of individual normal range of IOP is a personalized diagnostic criterion, which is more significant for evaluation of the risk of having or developing glaucoma than the upper limit of statistically normal range (21 mmHg).

Objective: to investigate intraocular pressure (IOP) and ocular blood flow (OBF) changes as well as the individual normal range of IOP in patients with age-related macular degeneration (AMD) with or without concomitant glaucoma after intravitreal anti-vascular endothelial growth factor (VEGF) therapy., Material and Methods: Group 1 included 34 patients (34 eyes) with AMD and no glaucoma, group 2-34 patients (34 eyes) with both AMD and glaucoma. In all patients the IOP and OBF were measured (with Ocular Blood Flow Analyzer) and the individual normal range of lOP calculated before the treatment, on the third day after the injection and at the 1-month follow-up visit. Statistical analysis was performed by STATISTICA 10., Results: In group 1 there were no significant changes in ocular blood flow at different times after ranibizumab injection. In group 2 a considerable decrease in OBF was detected 1 month after the injection (p<0.001). In group 1 the intraocular pressure was at the same level before and after the treatment. In group 2 the IOP significantly decreased on the third day after the anti-VEGF injection (p=0.03) but was back to the initial level in 1 month. The individual normal range of lOP, when calculated on the third day after the injection, appeared to be much lower than before due to a moderate decrease in both IOP and OBF. At the 1-month follow-up the individual normal range of IOP was back to initial values in non-glaucoma patients but remained low in the glaucoma group due to reduced OBF., Conclusion: The established decrease in the individual normal range of IOP in the late period after an anti-VEGF injection should be taken into account when managing patients with both AMD and glaucoma.

A clinical case of bilateral retropupillary implantation of iris-fixated lenses (Worst iris-claw intraocular lenses) in a patient with bilateral complete native lens dislocation into the vitreous body is presented. Despite native lens in the vitreous, the patient did not develop ocular hypertension in either eye after the surgery during a long-term follow-up period. Visual acuity significantly improved and there was no necessity in removing the dislocated lenses.

Purpose: To evaluate the early results of femtosecond laser application in phacoemulsification of cataracts of different density., Material and Methods: Femtosecond laser-assisted phacoemulsification cataract surgery was performed on 277 patients (390 surgeries) with II-IV degree lens nuclear density., Results: The use of femtosecond laser for capsulorexis and lens nucleus fragmentation enables forming of a well-shaped, properly sized, and accurately centered aperture in the anterior lens capsule, reduces the equivalent time of ultrasound exposure (by 30% in average) and decreases the total time of nuclear fragments emulsification by a third., Conclusions: Femtosecond laser-assisted phacoemulsification is a highly effective and safe surgical technique that takes the surgery to a new level. By analogy with cardiovascular surgery this direction of improvement of cataract treatmentmay be called "hybrid phacoemulsification". Hybrid approach in cardiovascular surgery is promising and progressive. It combines the possibilities of conventional and minimal invasive endovascular surgery, considerably reducing intraoperative trauma during open-heart procedures. In cataract surgery the use of femtosecond laser in combination with classical ultrasound phacoemulsification enables closed-eye performance of certain technical stages that are usually fraught with complications.

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 presents the results of an experimental and morphological study of combined antiangiogenic effect of photodynamic therapy with Photosens photosensitizer and Avastin (bevacizumab) on neovascularization process in corneal stroma. The combined approach has demonstrated an advantage over separate application of these methods, what, however, has to be proved clinically.

Currently accepted selective principle of modern therapeutic-optical keratoplasty is based on well-known advantages of target substitution of the damaged corneal layers. This article covers the variety of selective keratoplasty methods for different anatomical levels of corneal involvement. Major advantages of up-to-date keratoplasty methods involving high end surgical technologies have been analyzed.

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.

Outcomes of different modifications of top-hat keratoplasty were assessed in 48 patients (48 eyes) with bullous keratopathy. In the 1st group manual top-hat keratoplasty was performed in 7 patients. 30 patients of the 2nd group underwent manual half-top-hat keratoplasty. In the 3rd group femtosecond laser-assisted top-hat keratoplasty was performed in 11 patients. All keratoplasty techniques used in the study provide high rate of clear graft retention. Manual half-top-hat keratoplasty is technically easier compared to manual top-hat keratoplasty though having similar outcomes and does not require the use of any additional equipment. Femtosecond laser-assisted top-hat keratoplasty allows to achieve superior optical results, trephination is performed promptly and with minimal tissue trauma. This new keratoplasty technique is a promising procedure and requires further detailed investigations.

The results of different techniques of automated endothelial keratoplasty (EKP) performed in 72 patients with bullous keratopathy are estimated. Automated EKP with superficial flap was performed in 18 patients (1st group), Descemet stripping automated EKP (DSAEK) - in 26 patients (2nd group), Descemet stripping automated EKP (DSAEK) with thin grafts - in 20 patients (3rd group), Descemet membrane automated EKP with stromal rim (DMAEK) - in 8 patients (4th group). According to our results DSAEK with thin grafts is indicated to elderly patients with severe ocular disease (ocular comorbidities, repeated surgery, advanced keratopathy). DSAEK is a promising surgical technique allowing to achieve the best functional results. Nevertheless this procedure is technically challenging and is good for relatively functionally "preserved" patient groups.

Comparative analysis of functional results of contact lens correction and penetrating keratoplasty (PKP) in keratoconus are presented. To assess resolution ability we considered visual acuity and contrast sensitivity. 117 patients (219 eyes) with stage I-IV keratoconus, wearing rigid gas-permeable contact lenses (RPCL), and 60 patients (64 eyes) after PKP were examined. In 69% patients after PKP non-corrected visual acuity (NCVA) was 0.1 or more and mean best corrected visual acuity (BCVA) was 0.63, that is similar to efficacy of contact lens correction in stage III-IV keratoconus. In 31% patients NCVA after PKP was less than 0.1 due to significant refractive arrow, visual rehabilitation of these patients required use of RPCL or refractive surgery. Contrast sensitivity in medium frequencies after PKP was almost similar to that of contact lens correction in stage III keratoconus, and in high frequencies it was close to that of stage IV.

Comparative analysis of optic aberrations in contact lens correction and after penetrating keratoplasty (PKP) in keratoconus are presented. 117 patients (219 eyes) with stage I-IV keratoconus, wearing rigid gas-permeable contact lenses (RPCL), and 60 patients (64 eyes) after PKP were examined using OPD Scan (NIDEK, Japan) to assess aberration characteristics. Total optic aberrations and higher-order aberrations of ocular and corneal wavefront were significantly increased after PKP compared to those in patients with I-III stage keratoconus wearing RGCL. Astigmatic aberrations after surgery are increased compared to that in patients wearing RGCL regardless of keratoconus stage. Generally, according to objective aberrometry efficacy of PKP is similar to that of contact lens correction in IV stage keratoconus.

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).

Detailed analysis of copper compounds migration in the corneal stroma are presented. The biochemical conditions of the middle periphery of the cornea is found to inhibit copper ions movement to the center in patients with keratoconus due to increased tear alkalinity. Low concentration of dichlorocuprate (I) ion in the center of cornea results in inactivation of lysyl oxidase, an enzyme that catalyzes collagen cross-linking, and thus promotes keratoconus. Revealed association of tear acidity and copper distribution in cornea offers new opportunities in pathogenic treatment of keratoconus.

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.

New technical elements of complete corneal stromoplasty were practiced in an experiment on 25 isolated cadaver eyes; then 7 operations were clinically performed on 7 eyes according to the same procedure. The results have shown that the experimentally tested new technique may be successfully applied in the clinical setting.

The paper presents the results of practical application of a new screening method for determining tolerant intraocular pressure (TIOP) on a Blood Flow Analyzer (Paradigm, USA). Studies were conducted on 331 eyes (205 subjects). Group 1 consisted of 80 patients (126 eyes) without glaucoma being found, with intraocular pressure (IOP) in the average normal range, but with a TIOP excess of 1-8 mm Hg (a risk group); Group 2 included 15 subjects (20 eyes) without glaucoma with normal IOP in whom TIOP exceeded the existing IOP by 1-7 mm Hg; Group 3 comprised 110 patients (185 eyes) with Stage I-III primary open-angle glaucoma (POAG) with compensated IOP. Morphofunctional studies revealed glaucoma in 95 (75%) eyes in the risk group: Stages II and I in 61 and 30%, respectively; and advanced glaucoma in 9%. At the same time, there was a close correlation of the probable detection of glaucoma with the existing degree of a TIOP excess. No cases of glaucoma were observed in Group 2. The determination of TIOP and morphofunctional changes over time in Group 3 revealed a stable glaucomatous process in 99% of cases in which IOP was lower than or equal to TIOP, as well as progressive glaucomatous neuropathy in 91% in which compensated LOP exceeded TIOP. The results of the study in Group 3 suggest that the index TIOP may be used as a guide of IOP in the treatment and monitoring of POAG. The presented data indicate that the determination of the level of TIOP is a required element of both standard ophthalmological examination and monitoring of glaucoma.

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.

The effects of two 5-membered (SP5, SP6) endogenous synthetic peptide fragments of protein S100b on the course of regenerative-reparative processes in the corneas of Wistar rats were morphologically studied after making a graduated injury. Conjunctival or endonasal injection of the peptides was made at two concentrations of 10(-6) and 10(-8) M. The study peptides were found to have a modulating effect on regenerative-reparative processes regardless of the route of administration and to induce accelerated and qualitative corneal wound healing as compared with the controls. The specific feature of SP5 was the formation of a fibroblastic membrane. When SP5 was injected at a concentration of 10(-6) M, the membrane was more pronounced and occupied the whole area of keratectomy whereas when this peptide was administered at a concentration of 10(-8) M, its formation was observed in the deep and middle corneal layers. The most marked effect of SP6 revealed during the study was the formation of newly-formed vessels over the entire wound surface independently of the concentration of the injected substance. Of the two study peptide fragments, SP5 is, in the authors' opinion, promising for clinical application. Significant keratocytic proliferation noted in the use of SP5 at a concentration of 10(-6) M may be used to accelerate scarring when the sclera and cutaneous covering are damaged. The effects detected with administration of SP6 at two concentrations were regarded as negative as they did not answer the purpose set during the study performed.

Ultrasound and optical coherent biometries were used to study the influence of the biometric parameters of the anterior segment of the eyeball on the precision of calculation of the focal power of an intraocular lens (IOL). A clinical study has demonstrated that among the biometric parameters of the anterior segment of the eyeball, there is a close correlation of miscalculation of IOL focal power with the diameter of the cornea "from white to white" and accordingly with the diameter of the floor of the corneal segment. Based on the findings, the authors have developed a procedure for calculating the focal power of an IOL for cases of the disproportion of the corneal segment to the IOL length of the eyeball.

In 40 patients with terminal neovascular glaucoma of various genesis (visual acuity 0 to wrong light projection), 4 rectus muscles were tightly ligated at the insertion site of their strings to the sclera of the eyeball with silk threads under local anesthesia. The threads were not postoperatively removed and left under the conjunctiva (Invention Patent No. 2286752 of November 10, 2006). The proposed procedure for blocking the anterior ciliary arteries may be used as the method of choice in patients with terminal neovascular glaucoma. It makes it possible to achieve a steady-state reduction in intraocular pressure, by improving humor outflow from the corner of the anterior chamber, to diminish or completely eliminate pain syndrome and corneal edema, by maintaining the mobility of the eye in corpore, and to avoid enucleation.

This comparative clinical study has indicated the importance of correctly choosing a formula to calculate the focal power of an intraocular lens (IOL) in the short ocular anteroposterior axis (APA). The most accurate and comparable formulas SRK II and SRK/T at the mean ocular APA values have significant errors at an APA of less than 21 mm. The new empirical formula allows the accuracy of calculation of the focal power of IOL to be increased in the short ocular APA as compared with other currently used formulas.

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 paper presents the results of studying the photofungicidal activity of a photosens (octacationic phthalocyanine) in the in vitro and in vivo systems. Cultured Candida guilliermondii were employed in in vitro investigations. The single combined action of octacationic phthalocyanine at a concentration of up to 1 microM and laser irradiation at a wavelength of 675 nm were established to allow the high activation (up to 100%) of yeast fungi to be achieved in the in vitro system. In vivo investigations were performed on 14 rabbits (28 eyes) with induced keratomycosis. In the first series, fluorescent diagnosis of photosens accumulation in the pathological corneal areas was made in 9 (18 eyes). Based on the data obtained in the second series of experiments, the authors examined the feasibilities of photodynamic therapy for corneal mycotic lesions with the above photosensitizer in 5 rabbits (10 eyes).

The impact produced by incisions of 2 examined types on the corneal refraction was studied in 40 patients (40 eyes) shared between 2 groups according to an incision type. 5 mm tunnel self-sealing incisions of 2 types, i.e. temporal corneal one longer by 3 mm, and upper linear sclerocorneal one stabilized by horizontal suture, were made use of. The obtained refraction was evaluated on week 1 and then in 1 and 3 months after surgery. Group 1 (surgical approach: 5 mm linear sclerocorneal tunnel incision): the mean value of induced astigmatism made 0.68 D during the initial 3 postoperative days, 0.62 D in 1 month after surgery and 0.73 D in 3 months after surgery. Group 2 (surgical approach: 5 mm temporal corneal tunnel incision): the above value made 1.1 D during the initial 3 postoperative days, 0.7 D in one month after surgery and 0.52 D in 3 months.

We conducted a study for the purpose of developing a phacoemulsification technique for patients with high myopia optimized for the specificity of myopic eye. The study involved 124 (165 eyes) patients with high myopia and cataract. The lens density in operated patients was of degrees II-IV according to Buratto. The anterior-posterior axis of the eyeball ranged from 26.5 to 34.00 mm. the patients were shared between the experimental (92 eyes) and control (73 eyes) groups with respect to a used surgical technique. A modified procedure was applied in the experimental groups and the basic technique was used in the control group. The time of lens extraction, the volume of used irrigation liquid and the frequency rate of intra- and postoperative complications were the criteria in efficiency evaluation. The study showed the modified surgical procedure of phacoemulsification to ensure a better visualization, to reduce the load on the lens ligamentous apparatus and to facilitate, as much as possible, manipulations made on the lens nucleus of myopic eye; it also cuts the time of cataract lens extraction, which ensures a less volume of used irrigation liquid.

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.

The study results showed a principle possibility to fragmentize the most dense lens nuclei by means of a nylon cutting loop. The safety and efficiency of applying a loop fragmentizer in phacoemulsification of high-density cataract were equally demonstrated. The method advantages are conditioned by that a preliminary splitting of the nucleus into fragments without trenches being shaped cuts essentially the total capacity and duration of ultrasound impact, thus, the irrigation time and the needed volume of balance salt solution also decrease intraoperatively: it, naturally, diminishes the generally-known traumatic aftermaths of surgical intervention.

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).

The parameters characterizing the mechanical properties of the cornea and of the adjoining scleral parts as well as the influence produced by radial keratotomy and excimer laser kerato-ablation on the rigid corneal features were studied. The conclusion is that such keratorefractive surgeries (radial keratotomy and excimer laser photo-ablation) worsen the resistant corneal properties. Although the corneal thickness remains unchanged after radial keratotomy, "conditionally weak" sections take shape in the zone of keratotomic scars, in which the probability of ruptures of the cornea at damages to the eyeball increases.

Clinical estimation of different modifications of phacoemulsification revealed the formation of the second tunnel in the nucleus for its division into quadrants in "four-quadrant phaco" increases the required duration of ultrasonography (US) and irrigation, which causes greater endothelial losses associated with the use of nuclear breakdown by means of a chopper tunnel. When the authors used their own methods of "extracapsular half-nuclei" fragmentation, endothelial losses are rather greater than those with the similar method "stop & "chop", which is associated with closer disposition of the US tip to the posterior corneal surface. At the same time nuclear breakdown by means a chapper in the capsular sac by the "stop & chop" method causes dilation of Zinn's ligaments, fraught by their rupture, particularly if latent derangement or defects of the zonular apparatus, and increases the risk of damage to the posterior capsule by the chopper.

A new method for cataract removal by phacoemulsification in impaired lenticular joints consists in fixation during surgery of the anterior lenticular chamber along the edge of the capsulorrhexis by 4 retractor hooks and subsequent implantation of a soft intraocular lens. The operation was performed in 6 patients with cataracts of different types complicated by subluxation of the lens. The operation did not involve such complications as vitreous prolapse or displacement of the incompletely dislocated lens. All operations were finished with complete evacuation of lenticular mass and implantation of soft silicone intraocular lenses. The proposed method widens the category of patients in whom modern phacoemulsification can be used.

A new form of refractive keratoplasty for the correction of myopia was developed using a new approach to the problem. The midperipheral annular area of the recipient cornea was deepithelialized, and Bowman's layer was removed using a special bore coated with diamond crumbs. A cryolathed annular graft was placed on this prepared midperipheral area of the recipient cornea concentrically with its center. As a result of subsequent reepithelialization inside the transplanted ring, a regular optically active surface was formed. The refractive effect gradually appeared eight to ten weeks after surgery This new optically active surface acted as a lens, consisting of epithelial cells on top of the host cornea. The method required neither cutting of the stroma nor any manipulation in the optical zone of the cornea. A new term "keratoepitheliomileusis" was coined for this new procedure. Eleven patients (12 eyes) with high myopia ranging from 7.5 to 22.0D underwent keratoepitheliomileusis. The refractive and visual results found after four to 16 months of follow-up are presented. Emmetropic refraction occurred in three patients. In the other nine eyes, the deviation from emmetropia ranged from 0.75 to 2.5D. In all patients, uncorrected visual acuity was improved considerably (up to 0.3 to 1.OD) without loss in their best-corrected vision.

The results of 48 surgeries (refraction epikeratoplasty) for aphakia, high ametropia, and keratoconus evidence the efficacy of such operation in the afore-said conditions. Further studies are necessary to elucidate the pathogenesis of complications, improve the technique of surgery and technology of the transplant preparation in order to make it more safe and improve its functional results.

The technique of refraction keratoplasty for correction of myopia has been developed. On the deep epithelial surface of the cornea a ring-like layer transplant made of frozen donor cornea has been transplanted. The mechanism of the refraction effect of the operation which developed in 2.5 months after the operation is based on the specific properties of the corneal epithelium. Re-epithelialization of the transplant and the central zone of the cornea after the operation leads to the formation of a new optically active surface acting as a negative lens from the epithelial tissue. Clinical assessment of a new technique has been made in 8 patients with high myopia (from 7.5 to 22.0 diopters).

The results of keratometry of 13 allotransplants have confirmed the rightfulness of the employed methods for calculation of the parameters of biolenses for epikeratophakia. For clinical application the initial intumescence should be taken into consideration, as well as the donor tissue thickening during its freezing for working on a lathe.