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Purpose. Determining the functional state of the outer and inner retina’s layers in patients with diabetes mellitus (DM) type 1 and 2 before the clinical manifestations and in the early stages of diabetic retinopathy (DR) using the methods of multifocal electroretinography (mfERG) and microperimetry (MP).Patients and methods. 91 patients were examined (182 eyes). The patients were divided into 4 groups: 1st — 23 people (46 eyes) with diabetes without DR (the duration of the disease is up to 2 years); 2nd — 22 people (44 eyes) with diabetes without DR (diabetes from 2 to 8 years); 3rd — 24 people (48 eyes) with NPDR on the background of diabetes; 4th — 22 people (44 eyes) of the control group (healthy eyes). In addition to the standard ophthalmologic examination, all patients were registered mfERG (FOK1) on the diagnostic equipment EP-1000 Multifocal (Tomey, Germany) and carried out MP using the device “MAIA” (CenterVue, Italy).Results. According to mfERG, it has been established that the components of mfERG, the biopotential density and the amplitude of P1, are most sensitive to diabetic changes. In groups with type 1 and type 2 diabetes, there is a significant decrease in the density of P1 in comparison with the control group (p < 0.005, Mann-Whitney test), as well as a decrease in the amplitude of P1 on almost all tested rings (p < 0.005). In all groups, there is an increase in the latency of P1 in the central ring (0–2.3°). According to MP data, it was found that patients with type 1 and type 2 diabetes showed a decrease in the average light sensitivity in comparison with the control group, however, our data are within the reference values, regardless of the presence or absence of clinical manifestations of PD.Conclusion. As a result of the study, early functional and morphological disorders of the neurosensory apparatus of the eye in diabetes were identified. It is proved that mfER and MP allow to detect violations at the preclinical stage of DR and are necessary studies for the dynamic control of the progression of DR.

Purpose: creation of working classification of morphologic variations of postoperative lens capsule opacity after Micro-Invasive cataract surgery. Material and methods. Morphologic study of the lens capsule (LC) has been conducted on 4 artiphakic cadaveric eyes. A specimen of an isolated anterior lens capsule, obtained during the repeated operation with changes characteristic for anterior capsular contraction syndrome has been studied too. The obtained specimens have been researched with the method of semithin sections. Results. The analysis of the morphologic cadaveric LC specimens revealed the polymorphism of secondary cataract (SC). Besides well known “classic” SC forms, which were caused by fibroplasias processes or pseudo-regeneration a new type of postoperative LC opacity not represented in the available literature before has been revealed. The given variant of opacities was called “pseudo-hyaloid” form and characterized by the absence of clear LC borders, changes of its normal structure, the appearance of loose fibrillar structure with microslit spaces and exfoliations, that possibly was the consequence of acustic cavitation, arising in the result of ultrasonic effect. As a result the LC lost characteristic for it the role of the dense bed and made impossible adhesion and migration on its changed surface the proliferative fibrocellular elements characteristic for “classic” SC forms. The microscopy results of the isolated anterior LC specimen in the area of capsulotomic aperture showed the presence of altered abundant loose fibrillar tissue with microporous structure and expressed forming of folds. Making layers of fibrous tissue exceeded the thickness of the normal anterior LC in 10 and more times and considerably reduced the diameter of capsulotomic aperture. Conclusion. The variety of postoperative LC opacities confirmed by the results of morphologic studies afforded to suggest a new working classification in which all possible morphologic variants and the stages of the secondary pathologic changes forming of anterior LC. The suggested classification is convenient for the understanding and must promote to make a right algorithm in the choice of optimal and safe technology of laser reconstructive interventions.

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Bioinorganic chemical composition of the lens of human and experimental animals (cows, dogs, rats, rabbits) have been analyzed in various studies. In most cases, the studies employed different methods to determine the gross (total) composition of chemical elements and their concentrations in the examined samples. Less frequently, they included an assessment of the distribution of chemical elements in the lens and correlation of their concentration with its morphological changes. Chemical elements from all groups (series) of the periodic classification system were discovered in the lens substance. Despite similar investigation methods, different authors obtained contradicting results on the chemical composition of the lens. This article presents data suggesting possible correlation between inorganic chemical elements in the lens substance with the development and formation of lenticular opacities. All currently employed methods are known to only analyze limited number of select chemical elements in the tissues and do not consider the whole range of elements that can be analyzed with existing technology; furthermore, the majority of studies are conducted on the animal model lens. Therefore, it is feasible to continue the development of the chemical microanalysis method by increasing the sensitivity of Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS) with the purpose of assessing the gross chemical composition and distribution of the elements in the lens substance, as well as revealing possible correlation between element concentration and morphological changes in the lens.