[Endocapsular fixation of intraocular lens in patients with ectopia lentis and Marfan syndrome (case study)]. / Endokapsulyarnaya fiksatsiya intraokulyarnoi linzy pri ektopii khrustalika na fone sindroma Marfana (klinicheskoe nablyudenie).

Modern trends in advancement of phaco surgery techniques in patients with ectopia lentis (including patients with Marfan syndrome) are characterized by the transition from complete removal of the lens (lensectomy) to aspiration of the lens substance and attempts to preserve and reposition the capsular bag. This case study analyzes the results of surgical treatment of bilateral ectopia lentis in a 6-year-old patient with Marfan syndrome. The specifics of microinvasive phaco surgery consisted in capsular bag preservation and endocapsular fixation of the intraocular lens. The article presents the results of ophthalmological observation over a seven-year period.

[Clinical and morphological characteristics of corneal epithelial dystrophy (clinical observations)]. / Kliniko-morfologicheskie kharakteristiki epitelial'noi distrofii rogovitsy (klinicheskie nablyudeniya).

This paper presents clinical observations that can be regarded as degeneration of the basement membrane of the corneal epithelium. Difficulties in identifying such forms of corneal dystrophies, on the one hand, are associated with limitation and polymorphism of the clinical picture, and, on the other hand, with insufficient information content of the basic diagnostic methods (i.e. the methods used during the initial examination). The presented clinical cases allow singling out the alarming and pathognomonic signs of the disease in the diagnostic algorithm. In the first case, attention should be paid to biomicroscopic changes in the superficial layers of the cornea and the optical defects, which can be regarded as a manifestation of an irregularity of corneal refraction. Identification of pathognomonic signs of the disease is possible on the basis of a detailed, close-to-morphological study of the structure of superficial corneal layers using confocal microscopy and optical coherence tomography. At the same time, the localization of the detected changes at the level of epithelial basement membrane and its basal sections is of crucial significance for substantiating the diagnosis. In addition, according to the literature data, recurrent erosions of the cornea of unclear etiology should be attributed to presumptive signs of degenerative changes in the basement membrane of the epithelium.

[Compensating the Descemet's membrane defect (a clinical case study)]. / Kompensatsiia defekta destsemetovoi membrany (klinicheskoe nabliudenie).

The article describes a clinical case of Descemet's membrane detachment that occurred during cataract phacoemulsification with implantation of intraocular lens. Significant corneal edema developed in the early post-op period. Considering the ability of endothelium to close its own defects even with large injury area, the patient was followed-up for 2 years. Corneal edema was treated during 4 months and concluded with instillations of osmotic and anti-inflammatory drugs. At 1.5-2 months of therapy, the edema was gradually decreasing, and by the 4th month of the follow-up the cornea was practically transparent. Density of endothelial cells in central cornea, where the Descemet's membrane was absent, comprised 1000 cells/mm2. Further observation revealed cornea staying transparent for 2 years after the surgery. Complete optical recovery of patients with Descemet's membrane defect in this case study is supported by similar clinical cases briefly described in the article, and evidence that structural functional recovery of the corneal endothelial layer is possible even when it has large defects (more than 2.5 mm in diameter).

[Corneal transparency: anatomical basis and evaluation methods]. / Prozrachnost' rogovitsy: anatomicheskaia osnova i metody otsenki.

Being just a relatively small part of the fibrous tunic of the eyeball, the cornea is, nevertheless, unique in terms of the variety of its functions. Because the cornea differs significantly from other protective frames in its structure, it provides the possibility of light transmission and strong refraction that largely contributes to the total refraction of the eye. The development of ophthalmology is impossible without improving methods of adequate anatomical and functional assessment of the eye not only as a whole, but also as a collection of interacting structures.In this regard, examination methods of the cornea have undergone significant advances in recent years. So far, the level of corneal transparency has been judged by biomicroscopy findings or indirect characteristics (thickness, structure, etc.). Confocal microscopy of the cornea and wave-based examinations involving one of the available laser interferometers (OCT or HRT) are also used. However, the data obtained with these methods resembles that of layer-specific reflectometry, i.e. the magnitude of directed reflection of the light beam from corneal corpuscles, which does not completely agree with the classical idea of transparency.

[Clinical results of aphakia correction with multifocal intraocular lenses]. / Klinicheskie rezul'taty korrektsii afakii mul'tifokal'nymi intraokulyarnymi linzami.

AIM: to assess visual functions and ergonomics after bilateral versus unilateral implantation of Lentis Comfort LS-313 MF15 multifocal intraocular lenses (MIOL) in aphakic eyes. MATERIAL AND METHODS: A total of 20 patients with М LENTIS LS-313 MF15 MIOLs were followed up. Group 1 consisted of 12 patients after bilateral symmetric implantation, group 2 - of 8 patients after unilateral procedure. The following parameters were examined: uncorrected binocular visual acuity at far, near, and intermediate distances under photopic and mesopic conditions, the range of pseudoaccommodation, spatial contrast sensitivity to achromatic sinusoidal gratings, lens stability with account to its optical design, and patient satisfaction with the resultant vision. RESULTS: In both groups, distance visual acuity was high under any lighting conditions. At near and intermediate distances as well as at 5-6 m, binocular visual acuity in group 1 was higher than in group 2, regardless of the lighting conditions. The range of pseudoaccommodation was 3.5 D and 3.25 D in groups 1 and 2, respectively. Spatial contrast sensitivity function appeared typical, with maximum values at intermediate frequencies and lower values at higher frequencies. None of the patients required distance correction. Of 32 eyes, 7 exhibited MIOL rotation of 10-25 degrees at 1 month after surgery, however, none of the patients presented complaints characteristic of IOL decentration. CONCLUSION: Bilateral symmetric implantation of М LENTIS LS-313 MF15 MIOLs has the advantage over a unilateral procedure, since it enables a wider range of pseudoaccommodation and less dependence on lighting conditions with no compromise of high visual acuity at far and intermediate distances.

[Reasons to reconsider interpretation of densitometry for corneal transparency]. / O neobkhodimosti peresmotra interpretatsii dannykh densitometricheskoi otsenki prozrachnosti rogovitsy.

AIM: To assess the effect of light scattering in the corneal epithelium on densitometric brightness of the stroma through mathematical modeling of the interaction between a light beam and the two-layer epithelium-stroma system. MATERIAL AND METHODS: In order to study the scattering behavior of a plane-parallel non-coherent beam at the epithelium-stroma interface, a multi-age group was formed (87 patients, 174 eyes) that comprised two subgroups with equal number of assign participants: healthy patients with no systemic changes and mixed patients with undisturbed corneal transparency that, nevertheless, were under instillation therapy. In the first subgroup, the assessment of light scattering was done at random times, while in the second subgroup - within the first 200 seconds after the instillation in order to avoid a reaction of the ocular surface structures, including epithelium (rapid response of epithelial cells to instillations). Light scattering intensity was measured with Pentacam (USA). The densitometric curve and brightness maxima of the epithelium and neighboring stroma as well as the mid and upper stroma were recorded for each patient. RESULTS: A physico-mathematical model of the interaction between a light beam and the two-layer epithelium-stroma system was created. The study confirmed our theoretical CONCLUSION: on the effect size of light scattering intensity on the apparent densitometric brightness of the stroma. CONCLUSION: Direct densitometry of multilayered spherical objects, of which each layer possesses its own optical properties, has been proved inaccurate. Complex optical interactions in a multilayered model cause a false increase in brightness of more transparent layers that lie behind those with pronounced light scattering properties. The function that describes the false increase in scattering ability of the layer that is more transparent rises sharply at the border between the layers.