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Introduction. Primary angle-closure glaucoma (PACG) remains one of the leading causes of irreversible blindness. Up to date, a significant amount of data has been accumulated concerning the biometric parameters of the eye in PACG, however, there is a lack of information on the dynamic characteristics of these parameters.Objective: to evaluate the dynamic biometric characteristics of the structures of the anterior segment of the eye in PACG.Patients and methods. The results of optical coherence tomography were analyzed in 40 patients with PACG and in 40 patients without signs of hydrodynamic disorder. The studies were carried out under photopic and mesopic illumination conditions. The scanned images were obtained using an RTVue-100-2 optical coherence tomograph device (Optovue, USA). Biometric measurements were performed using standard tomograph software; volumetric studies were carried out based on the Pappus-Guldinus theorem with additional constructions. When analyzing the obtained images, 13 different linear and volumetric parameters were evaluated.Results. A decrease in the parameters reflecting the features of the configuration of the anterior chamber of the eye was noted in the presence of PACG (width of the ACA, depth and volume of the anterior chamber). From the point of view of the possible influence on the state of the anterior chamber angle, it is necessary to highlight changes in such indicators as the area, volume and thickness of the iris. Regardless of the conditions of the examination, these indicators, on average, were significantly higher in the PACG and practically did not change with a decrease in the level of illumination. At the same time, in the absence of disturbances in hydrodynamics under mesopic conditions, despite an increase in the thickness of the iris, a significant decrease in its area and volume was noted.Conclusion. Biometric changes in the structures of the anterior segment of the eye in the case of PACG relate not only to linear, but also to volumetric indicators. As a certain component of hydrodynamic disorders in the case of PACG, the revealed preservation of the iris volume during pupil dilation under mesopic illumination conditions should be considered, while in the absence of hydrodynamic disorders, this indicator decreased. Therefore, not only static changes in the biometric characteristics of the structures of the anterior segment of the eye, but also their dynamic fluctuations, should be considered as a risk factor for clinical manifestations of PACG, which determines the practical significance of dynamic biometric studies in the examination of patients with suspected PACG.

Introduction: penetrating keratoplasty (PK) is an effective method for the surgical treatment of corneal failure and its layers and low visual acuity. It is well-known that the graft degrades over time, it is associated with “chronic immune destruction”. Rekeratoplasty is conducted in case of rapid decrease of transplant functions, but even with multiple rekeratoplasty iterations, the result can be unstable.Patient and methods. Patient D., 42 years old, complaints to low vision of left eye — arm movement 10 cm on face. Both eyes have been previously surgically operated for the last 10 years. Two iterations of an artificial iris transplantation in combination with IOL implantation, and Ahmed drainage implantation and five rekeratoplasty on the left eye were conducted. Corneal graft failure with transplant thickness — 802 μm. The patient suffers from Mediterranean fever and polyarthritis. We conducted a course of conservative therapy, which increased visual acuity to 0.05. Then we performed a surgical procedure for hybrid type of keratotransplantation. The following procedures were gradually conducted: mechanical removal of epithelium, femto-laser formation in a recipient’s replaceable corneal disk formation with 500 μm thick and a diameter of 7.0 mm, removal of disk, femto-laser formation of a central penetrating hole with a diameter of 3 mm opposite the artificial pupil, placing of the hydrogel graft 60 μm thick on the bottom of the bed. Hydrogel graft was covered by a donor corneal graft, which was fixed by interrupted sutures and soft contact lens.Results: Visual acuity of the left eye after 1 day after keratoplasty — 0.2; after 1 month — 0.3, the transplant was transparent; after 4 months — 0.4 with complex correction — 0.7, the transplant was transparent, the thickness of the donor disc — 275 μm.Conclusion. After multiple rekeratoplasty iterations the presented method of combined keratotransplantation allows to obtain a non-permanent effective result. At the same time, the polymer metabolism is preserved, since it has a circulation with the front camera. The case requires further observation.

The article substantiates the feasibility of studying the issue of seed germination of iris species under conditions of introduction. The viability of iris seeds from the subgenus Limniris (Iris ensataThunb.,Iris pseudacorusL.,Iris sanguineaDonn ex Hornem.,Iris setosaPall. ex Link,Iris versicolorL.) andXyridion(Iris carthaliniaeFomin,Iris gramineaL.,Iris orientalisThunb.) was estimated during long-term storage. Morphological and biological parameters of experimental seeds were descripted. The literature data on fast and one-time germination of seeds in representatives of the subgenusLimniriswas confirmed. The seeds of this group began to germinate after 21-36 days from sowing them in pots. In theXyridiongroup, seedlings appear after 2-4 months. The shortest period of seed germination (30 days) was observed forIris pseudacorus, the longest (2 years 7 months) - forIris graminea. The germination of iris seeds in moist habitats (subgenusLimniris) lasts for 4-6, the steppe species (subgenusXyridion) - 9-11 years.

The purposeof the study was to examine the effect of the intraocular lens (IOL) position in the probability of occurrence of the phenomenon of light reflection from its surface and to justify the method of its reduction from the standpoint of the optics laws and eye anatomical parameters.Methods.Based on the laws of physical optics, the reflection of light from the surfaces of the IOL was calculated. The phenomenon of light reflection from the IOL was analyzed, in particular, influence such factors as the lens position in the eye and pupil diameter on its occurrence.Results.It was found that with increasing of distance from the iris to posterior chamber IOL, the angle of appearance of the phenomenon of light reflection from the lens decreases significantly, with the most significant change (angle narrowing from 80° to 19°, i.e., 4.21 times) with increasing of the distance from 1 to 3 mm, which is quite achievable at the present stage of intraocular correction. It was shown that the pupil diameter is less influences by appearance of the phenomenon of light reflection from the lens: it is significant only at a minimum distance from the iris to the IOL (the position of the standard posterior chamber IOL) and insignificant when the IOL is removed from the iris. The obtained results demonstrate the optimality of the method for preventing the appearance of the phenomenon of light reflection from the IOL by removing the intraocular lens from the iris at a distance corresponding to the position of posterior capsule of native lens.Conclusions.In this study, on the basis of the laws of physical optics and mathematical calculations, the leading role of such factor as the IOL position in the eye in appearance and intensity of the phenomenon of light reflection from the lens is substantiated for the first time. The proposed method for reducing the appearance of the phenomenon of light reflection from the IOL, which manifests itself in the form of glare in the eye, visible to others, on the basis of increasing the distance from the iris to the IOL is the optimal solution to the important problem of improving the quality of life of patients with pseudophakia.