№2, 2020, volume 16

The purpose of the study is to develop an objective method for calculating the square of the iris defect area. Material and Methods. Clinical and functional surgical treatment results for 98 patients (98 eyes) with the consequences of traumatic damage of the eyeball's anterior part were analysed. The uncorrected visual acuity (UCVA) was 0.12±0.05, and the best corrected visual acuity (BCVA) was 0.41±0.15. Results. In orderto objectively assess the iris defect area, we developed a grid palette. We calculated the square of iris defect area using this palette in percent, after this surgical algorithm was determined. The visual functions in all patients after the treatment were increased and by the seventh day after the surgery were as follows: UCVA0.58±0.28; BCVA0.71±0.15. Conclusion. Using the designed palette for objective assessment of the iris defect area helps to choose the correct algorithm of surgery. In cases when the iris defect square is less than 30%, it is possible to use the technique of closed iridoplasty with patients own eye tissues. If the iris defect area is more than 30%, implantation of the iris-lens diaphragm is recommended.

The purpose of the study is to investigate the distribution of the amplitude and time parameters of visually evoked potentials and their relationship with the psychophysiological indicators of the visual analyzer in visual acuity "hand motion". Material and Methods. Data from 85 eyes were analyzed: 36 eyes with predominant impairment of retinal functions, 36 eyes with predominant impairment of the optic nerve, and 13 eyes with the predominant impairment of the optical media of the eye. The LED flash response was registered on the Neuro-MVP-4 device. The severity of detection was assessed using the CAMEL software. The threshold of electrical sensitivity was measured on the ESOM-Comet device. Results. All the parameters under study had a significant variation. The latency of flash VEP components had statistically significantly higher values in the group with predominant dysfunction of the optic nerve (p<0.01). The amplitude of the VEP was significantly higher in the group with the impairment of the transparency of optical media of the eye (p<0.01). There were no close correlations between the amplitude-time parameters of the flash VEP and the psychophysiological parameters of the visual system (т<0.20, p>0.05). Conclusion. The methods under study can be used with different efficiency in monitoring the functional state of the visual analyzer. The obtained data indicate the need for comprehensive assessment of visual functions in the non-visible area for effective monitoring of residual visual functions.

Choroidal melanoma refers to malignant tumors characterized by high aggressiveness in terms of local distribution, the occurrence of loco-regional and distant metastasis, which determines its high social value. The risks of metastatic disease depend on the size of the tumor, timing of observation, clinical and morphological characteristics and genetic factors. This review presents data on the study of aspects of the development and growth of choroidal melanoma, in terms of neoangiogenesis and the phenomenon of vasculogenic mimicry, the capabilities of indocyanine green angiography in identifying abnormal vascular network of the tumor. The relevance of this question is determined by the characteristics of the development of choroidal melanoma, which can occur as de novo or by malignant transformation of pigmented nevi and the critical point for its development is the tumor thickness of more than 2 mm, which starts the process of neoangiogenesis. Indocyanine green angiography, which is aimed at the identification of vascular network of choroidal melanoma plays an important role not only in the differential diagnosis of this pathological condition, but is of considerable practical interest in planning treatment, assessing its effectiveness and predicting the risk of metastatic process development. Methods used to find, select, obtain information and synthesize data: search for information on the Internet: Google Scholar, PubMed, eLibrary. The number of sources is 39 (from 1974 to 2019).

The purpose of the study was to conduct comparative analysis of the accuracy of IOL optical power calculation for eyes with an axial length of 20-22 mm and 22-24 mm. Material and Methods. 147 eyes of 104 patients were included in the study. The study group (I) included 56 patients (81 eyes) with short eyes (average axial eye length 21.17±0.56 (20.02-21.98 mm). Comparison group (II) consisted of 48 patients (66 eyes) with a normal axial length of 22.75±0.46 (22.0-23.77) mm. The IOL optical power was calculated using the SRK/T formula, and the retrospective comparison was made using the Hoffer-Q, Holladay 2, Olsen, Haigis and Barrett Universal I formulas. Results. Group I was characterized by statistically insignificant (p<0.05) differences in the average estimation error for Holladay 2, Hoffer-Q, SRK/T, Olsen and Barrett Universal II formulas (0.19±0.14, 0.23±0.08, 0.15±0.09, 0.21±0.13 and 0.17±0.21 D respectively). When using the Haigis formula, the smallest average estimation error was obtained (0.11±0.02), the differences are significant at the trend level (0.05

The purpose of the study is to assess the effect of vitreoretinal interface changes in patients with diabetic macular edema as far as the effectiveness of anti-VEGF therapy is concerned. Material and Methods. The study included 198 patients (198 eyes) with diabetic macular edema (DME). Two groups were formed: group 1 — patients without pathological changes in vitreoretinal interface (VRI); group 2 — patients with pathological changes in VRI. We studied the best-corrected visual acuity according to the Snellen table, central retinal thickness and VRI condition according to optical coherence tomography before the intravitreal administration and 1 month after. Results. Significant differences in best-corrected visual acuity were observed before and 1 month after intravitreal administration in both groups (p<0.05). A significant decrease in central retinal thickness in both groups was revealed (p<0.001). A statistically significantly larger average decrease in the thickness of the central retinal in group 1 was obtained (p<0.001). Conclusion. Improvement in visual acuity is significant in anti-VEGF therapy of DME with normal VRI, while with the pathological VRI it is not significant. The degree of improvement in average visual acuity and the degree of decrease in the average thickness of the central retina during anti-VEGF therapy of DME is significantly lower in the presence of VRI pathology. Presence of the vitreoretinal interface pathology reduces the effectiveness of antiangiogenic therapy of DME.

The purpose of the study is to evaluate the efficiency of combined operations with the use of allogeneic biomateri-als in patients with eyelids cicatricial entropion. Material and Methods. The group under study included 45 patients (50 eyes) aged from 5 to 71 years with cicatricial entropion and trichiasis of eyelids. The patients underwent reconstructive operations with the use of the allograft for eyelid plasty, allotendinous sututres and automucous membrane of lip. The efficiency of the performed operations was evaluated according to the following criteria: the position of the eyelid margin; the width of the palpebral fissure, the degree of the eyelids closure and presence of lacrimation. Results. In the early postoperative period (up to 14 days), all patients had correct position of the eyelids margin and narrowing of the palpebral fissure (up to 7-8 mm, absence of lagophthalmus. 9 patients still had lacrimation. In the long-term follow-up period (up to 3 years), we observed complete elimination of entropion, restoration of the palpebral tissue size and complete closure of eyelids in all patients. Conclusion. The use of the allogeneic biomaterials in the reconstruction of the eyelids with cicatricial entropion allows to eliminate eyelids deformation, lacrimation and lagophthalmus; to restore anatomical position and lost functions of the eyelid. The results of the study showed that it is possible to use the combined surgical intervention with simultaneous use of allogeneic grafts and automucous membrane of lip for complex cases of eyelids entropion.

The purpose of the study is to analyze clinical and functional treatment outcomes and usefulness of visual rehabilitation in patients implanted with IOL Lentis Comfort. Material and Methods. 64 patients were examined. Patients of group one underwent cataract phacoemulsification with IOL Lentis Comfort implantation, patients of group two were implanted with IOL Acrysof Restor. Non-corrected and corrected distance visual acuity, for intermediate distance (70 sm) and near visual acuity (30-40 sm) were examined on the 2nd day, in a month and in 6 months postoperatively. In 6 months after surgery subjective assessment of patients' satisfaction with the quality of vision was conducted using a questionnaire. Results. High distance visual acuity was revealed in both groups, visual acuity for intermediate distance was significantly higher in patients of group one, near visual acuity was higher in patients of group two. According to the questionnaire results patients of both groups did not experience difficulties in working and driving during the day, at night, patients of group two were much more likely to report difficulties in driving a car and undesirable light phenomena. Conclusion. Implantation of IOL with low-addition power and asymmetric optics provides high quality vision at various distances. The low level of undesirable light phenomena contributes to rapid adaptation of patients in the postoperative period.

The purpose of the study is to reveal the morpho-functional relationship dynamics of allografts and the recipient's nervous system based on the experimental model of the mimic musculature reinnervation. Materials and Methods. The experiments were carried out on Chinchilla rabbits (n=36). Facial nerve transection has been performed on all animals. No other manipulations were performed in the control group (n=9); in the 1st experimental group (n=12) an autograft fragment of the masseter muscle with a neurovascular bundle was fixed to the denervated cheek muscle. In the second experimental group (n=15) a complex of allogeneic biomaterials namely, "Regeneration stimulator" and "Vasculogenesis stimulator" was inserted between specified muscles. The animals were removed from the experiment on the 10-th, 30-th, 60-th and 180-th days. Tissue pieces from the operation zone were analysed with the use of transmission electron microscopy method. Results. It was established that compensatory-restorative processes in the control and 1st experimental group ended in scarring of the border zone and contracture of the mimic muscles. In the second experimental group we revealed a mimic musculature revascularization, as well as ingrowth of axons into the muscle and restoration of the neuromuscular synapses. Conclusion. Allogeneic biomaterial transplantation creates adequate conditions for restorations of the organic vascular bed and innervative apparatus of the denervated mimic muscles. The obtained results of the experiment can be regarded as one of the examples of the interlevel relationship restoration in the system following the use of allogeneic biomaterials.

The purpose of the study is to estimate the results of deep anterior keratoplasty in the treatment of keratoconus during the period of time from 2016 to 2020 based on Tambov branch data. Material and Methods. The main group included 26 patients (28 eyes) diagnosed with III-IV degree keratoconus and undergone deep anterior lamellar keratoplasty (DALK). The control group included 11 patients (12 eyes) with penetrating keratoplasty (PK). All patients underwent ophthalmologic examination before and after surgery, including routine and special (keratotopography, keratopachym-etry, endothelial biomicroscopy) methods of examination. Results. The prevalence of keratoconus in Tambov region is 0.59%, moreover keratoconus occurs in men 2 times more often than in women. Transparent engraftment of the transparent cornea was obtained in 100% of DALKs and only in 84% of PKs. In the group of patients with PK all changes in corrected visual acuity were statistically insignificant, while in the group of patients with DALK they were significant at all stages of examination. One year after surgery the corrected visual acuity was 0.64±0.23 and 0.57±0.27 in the main and control groups correspondingly (p<0.05). The endothelial cell loss one year after surgery was 10.5 and 5.1% following DALR and PK correspondingly (p<0.05). Conclusion. The analysis of DALK and PK outcomes in patients with keratoconus shows that DALK is characterized by shorter period of rehabilitation, absence of rejection reaction, stable visual acuity restoration, and lower rate of endothelial cell loss.

The purpose of the study is to identify morphological aspects of replacement of xenogenic decellularized elastin matrix (DXEM) transplanted into a bone defect of the upper wall of the rat's eye socket. Materials and Methods. The experiment was performed on 60 Wistar rats, which produced a 7x4 mm defect in the upper edge of the orbit. DXEM was placed in the defect zone, in the experimental group (n=30). The size was similar to the defect and was fixed with a suture material-silk 50 microns. Soft tissues were sutured in layers in the control group (n=30). Tissue excision was performed after 1, 3 and 12 months. Histological, immunohistochemical and electron microscopic methods were used. Results. DXEM was gradually replaced by bone tissue against the background of a pronounced reaction of CD68+/MMP-9+ macrophages. This indicated its resorption and lysis. Osteogenesis occurred endesmally, periostally, which was preceded by centripetal migration of endothelial kidneys with subsequent differentiation into hemocapillaries and growth of loose fibrous connective tissue with progenitor cells. The microenvironment could contribute to differentiation of progenitor cells in the osteogenic direction and osteogenesis represented by reticulin fibers, TGFb, sulfated glycosaminoglycans in the control group, the defect remained open throughout the experiment. Conclusion. Decellularized biomaterial based on elastin matrix has osteoconductive and osteoinductive characteristics and can serve as an adequate biomimetic for bone defects restoration.