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This report gives a general overview of embryological features of the human eye. Key literature sources published during the last century on evaluation of congenital changes in the vitreous body and identification of signs of its 'underdevelopment' in certain types of congenital cataracts have been studied. The said changes were analyzed in terms of general pathology of the human body as well as local morphological manifestations. According to the authors, such an approach justifies the need for comparison of clinical manifestations of congenital lens and vitreous changes with possible embryonic defects.

Aim: To analyze changes and identify specific signs of underdevelopment of the vitreous body in certain types of congenital cataracts., Material and Methods: A total of 26 patients (52 eyes) with congenital changes in the lens and vitreous were examined by means of digital spatial ultrasound imaging., Results: On the basis of multiplanar ultrasound examination and three-dimensional virtual modelling of the eye, spatial ultrasonographic characteristics of combined congenital involvement of the lens and vitreous have been determined. The changes revealed are shown to be morphologically related., Conclusion: The results suggest three-dimensional digital ultrasound virtual modelling useful for studying combined congenital changes in the lens and vitreous and, thereby, it enables 'decoding' of some elements of their normal morphology.

Aim: to study the nature of intraocular lens (IOL) opacification depending on the patient's ocular status and general condition., Material and Methods: A total of 9 patients (9 eyes) with 3-6 year history of progressive IOL opacification were enrolled. All the IOLs were acrylic (either hydrophilic--7 cases, or hydrophobic--2 cases). Two patients had their IOLs exchanged due to opacification. Six patients earlier underwent glaucoma surgery. Two patients were type 2 diabetic. Slit lamp biomicroscopy and optical microscopy were used for IOL examination., Results: The surface of hydrophilic acrylic lenses appeared bumpy because of multiple variously shaped translucent granules separated by a chaotic network of furrows and microfractures and located predominantly in the optic zone. In a more severe case, a bowl-shaped impression was observed in the area of opacification. Surface changes of hydrophobic acrylic lenses were in the form of isolated and confluent glistening formations (microcavities)., Conclusion: Signs of IOL degradation develop over a long period of time (3-6 years, in our experience) and mostly involve the anterior surface of the lens optic. Ocular comorbidity, glaucoma in particular, as well as other surgery and/or therapeutic treatment following IOL implantation may contribute to its opacification. Analysis of published data and own observations suggest that hydrophobic IOLs should be preferred in patients with concomitant diseases, especially diabetes mellitus. Granular deposits, if accumulate, may lead to deformation of the lens optic, as confirmed by the bowl-like impression in one of the explanted hydrophilic IOLs.

Comparative study of lens biomicroscopy in cataract of different etiology (senile, ultraviolet, radioactive and combined ultraviolet- radioactive exposure) is performed in experiment on animals (mice). Lens opacification pattern was showed to be similar in aging as an endogenous factor and ultraviolet (UV) and radioactive exposure as exogenous physical factors. Specificity of these factors is expressed in degree of damage only. Depending on damaging potential the factors may be arranged in a following way (in increasing manner): aging, ultraviolet irradiation, gamma-irradiation, gamma+UV-irradiation.

Microscopic lens changes are studied in mice (F1C57B1XCBA) depending on age and after ultraviolet (UV), gamma-irradiation and their combination. In all animals compared to young 3-months animals nonspecific changes due to aging were revealed: microvacuoles in cytoplasm of fiber cells, flattening of epithelial cells and nuclei fragmentation, swelling and confluence of cortical layer cells in anterior and posterior subcapsular zones. In epithelial cells the following changes were noted: nuclei polymorphism, cavities in a cell layer formation of multilayered structures of fibroblast-like cells and cell desquamation. Degree of nuclei vacuolization was significantly lower in groups with gamma- and gamma+UV-irradiation but higher in a group of UV exposure. The number of cells per unit area was significantly decreased in a group of gamma-irradiation after 7 and 10 months of exposure. Aging and UV exposure caused decrease of nuclei area, whereas affect of gamma-irradiation depended on proliferative capacity of cells: size of central cells increased and of peripheral cells reduced. Specific changes were not revealed for any of the factors.

Using differential electrophoresis protein composition of lens major proteins in hybrid mice F1 (C57B1XCBA) with cataracts of different etiology (senile, ultraviolet, radioactive and combined ultraviolet-radioactive exposure) was studied Changes that may be specific for cataract caused by aging, ultraviolet and/or gamma-irradiation were not revealed in water-soluble and water-insoluble protein fractions.

Four randomized groups of male mice F1 (C57Black/CBA) were investigated: a) UV-irraidated (UV-A, 15 min daily during 9 months, dose 5.6 + 1.2 W/m2), b) gamma-rays irradiated (2 Gy), single, c) influence for combination of UV- and gamma-rays treatment, d) aging. The lens opacities were measured on 7th and 10th month. The expert method based on six grade scale was used for cataract measure. On 7th month the median of lens opacities were Aging group = 0; UV-irradiated group = 2.5; gamma-irradiated group = 4.75; gamma- and UV-irradiated group = 6.0. The difference between all groups was significant (p < 0.004, Kruskall-Wallis ANOVA test). The Conover post hock test has shown the significant difference for all comparison pairs (p < 0.002) with the exception of UV-irradiated group, gamma-irradiated group, gamma- and UV-irradiated group. On 10th month the lens opacities were strongly increased: Aging group = 2.5; UV-irradiated group = 5.0; gamma-irradiated group = 6.5; gamma- and UV-irradiated group = 7.5 (median). The difference between groups was significant (p < 0.0001, Kruskall-Wallis ANOVA test). The Conover post hock test has shown the significant difference for all comparison pairs (p <0.003) with the exception ofthe UV-irradiated group and gamma-irradiated group. The formation of the specific lens opacities for any group was not found. Morphology and protein composition have been investigated on 10th month. The results of morphological changes study show destructive and degenerative impairments of capsule, epithelium cells and lens fibers. However, no specific changes related to some particular actions have been found. In addition, there were no specific changes of protein composition of both water-soluble and water-insoluble fractions estimated with Differential Gel Electrophoresis technique. Obtained data mean that aging, UV-treatment, and gamma-radiation causes the similar changes of lens. It was supposed that UV-treatment or/and gamma-radiation act as an aging factor on the lens.

There is a potential of therapeutic action on certain stages of caractogenesis, in particular on the aggregation of water-soluble proteins of cytoplasmic lens fiber cells, giving rise to insoluble protein complexes. The effect of a combined preparation (N-acetyl carnosine and D-patethine), acting by the chaperon-like mechanism, was studied in vivo on a prolonged rat model of UV-induced cataract. The use of the combined preparation consisting of a mixture of peptides of N-acetyl carnosine and D-patethine in a ratio of 1:1 as ocular instillations and intraperitoneal injections could slow down the development of UV-induced cataract in vivo. Pathomorphological studies suggest that the combined preparation has a protective effect on lens tissue when the rat model of UV-induced cataract is employed.

To study the mechanisms of action of new-generation anticataract drugs, it is necessary to have an accessible and adequate model of age-related cataract. A model of UV-induced cataract is pathogenetically closest to that of age-related cataract. A prolonged rat model of UV-induced cataract developing within 10 months is proposed; the clinical features of UV-induced cataract have been established at different stages of its development. A moderate homogeneous cloud-like lenticular opacity was observed at the end of the experiment; a less pronounced homogeneous opacity was seen in the anterior and posterior cortical layers. Cataract development was assessed by the appraisal method using the developed rat lenticular transparency scale, as well as by microdensitometry of biomicroscopic lenticular optical sections. Within the proposed model, the pathomorphological lenticular changes are largely similar to the histological pattern of age-related cataract.

Lenses from patients with glaucoma and senile cataract (control) were examined under electron microscope. Ultrastructural changes in the lenses of glaucoma patients differ from changes in senile cataract by a more pronounced thinning of the capsule and development of microdefects in it and in many cases by accumulation of amorphous material on the surface of the posterior capsule adjacent to the vitreous body. This material may be pseudo-exfoliate or a manifestation of stratification of the posterior capsule proper. Development of a pseudomembrane on the surface of posterior capsule is a manifestation of proliferative processes in glaucoma. These features in a certain measure reflect the mechanism of cataract development in glaucoma, which helps plan the measures for preventing it. The status of posterior lenticular capsule in glaucoma is to be taken into consideration when implanting intraocular lenses.

Eighteen cases (28 eyes) with congenital cataracts are analyzed. Transciliary lensectomy technique was used for cataract extraction (the ages of the infants at the moment of surgery varied from 3.5 to 16 months), aphakia was corrected by highly hydrophilic soft contact lenses worn during the daytime. The limbic vessels, corneal epithelium, endothelium, and thickness were examined. No changes in the epithelium were revealed. Only in one case a trend to a moderate dilatation of a limbic vessel in the upper segment was seen in the presence of microphthalmia. Analysis of endothelial morphometry data has revealed a universal tendency in all the cases: cell square increased and their density reduced (by 45 and 19%, respectively) immediately after surgery. Wearing of contact lenses was associated with a somewhat rise of the cell count, this count persisting below the norm by 10% on an average. Corneal thickness increased by 0.05 mm after surgery and by 0.03 mm during lens correction.