[Intraoperative optical coherence tomography in vitreoretinal surgery]. / Intraoperatsionnaya opticheskaya kogerentnaya tomografiya v vitreoretinal'noi khirurgii.

This article reviews literature on the use of intraoperative optical coherence tomography (iOCT) in vitreoretinal surgery, describes the historical aspects of the development of this technology from portable devices to optical coherence tomographs integrated into the surgical microscope, considers the advantages, limitations and disadvantages of this technology, which are now becoming obvious due to the accumulated experience. The review also explores the prospects for the development of iOCT and possible ways to solve its problems. In addition, the review presents and systematizes clinical findings that can be revealed with iOCT in such diseases as rhegmatogenous retinal detachment, complications of proliferative diabetic retinopathy, macular pathology, etc.

[The development of laser technologies in vitreoretinal surgery (publications review)].

The article presents review of scientific publications on development of laser treatment methods in vitreoretinal surgery. The use of photo-therapy in medicine dates back to ancient times, when people began to use sunlight as treatment of various diseases. The heyday of photo-therapy falls on the second half of the XIX century, which was associated with the invention of first electric lamps. In 1960, T. Maiman developed the world's first laser, revolutionizing precision and control of light delivery. This was the beginning of heyday of laser surgery primarily in ophthalmology, where potential of lasers was instantly recognized. The subsequent discovery of argon laser in 1964 by W. Bridges (USA) marked new era in retinal photo-coagulation. Then new types of lasers with various systems of delivering laser radiation appeared that significantly expanded range of application of laser technologies in ophthalmology and vitreoretinal surgery. Currently, the lasers are applied in oculoplasty, refractive and corneal surgery, in laser support of phacoemulsification of cataract, in treatment of glaucoma, in laser coagulation of retina and thermotherapy. In vitreoretinal surgery laser technologies remain at the level of the XX century. Thus, they are still applied only for endolaser coagulation of retina. And this despite the fact that there is immense potential for applying lasers as "laser scalpel" to remove vitreous humor, epiretinal fibrosis, retinotomy and choroidotomy.

[Modern concepts of pathogenesis of diabetic retinopathy]. / Sovremennye kontseptsii patogeneza diabeticheskoi retinopatii.

This literature review presents modern view on the pathogenesis of diabetic retinopathy (DR) paying particular attention to the molecular mechanisms leading to its development, as well as the manifestations of retinal neurodegeneration in such patients. Assessment of this condition and its clinical manifestations makes it possible to diagnose DR at the stage of absent initial vascular changes. Investigating the neurodegeneration mechanisms could supplement the existing understanding of the disease pathogenesis and could possibly help find new ways of treatment and prevention of DR.

[The role of neurodegeneration biomarkers in the management of patients with diabetic retinopathy]. / Rol' biomarkerov neirodegeneratsii pri diabeticheskoi retinopatii.

This literature review focuses on the role of disease biomarkers in the management of patients with diabetic retinopathy (DR) investigating in detail the problem of retinal neurodegeneration in such patients. Identification and assessment of the significance of qualitative and quantitative biomarkers of DR and neurodegeneration can complement screening examination, as well as help predict the course of the disease and the response to therapy. A comprehensive analysis of these factors allows for effective treatment and prevention of complications in patients with DR based on prognostic models and dynamic monitoring of these indicators.

[Viscodissection with staining of epiretinal membranes in surgery of proliferative diabetic retinopathy]. / Viskodissektsiya s kontrastirovaniem epiretinal'nykh membran v khirurgii proliferativnoi diabeticheskoi retinopatii.

PURPOSE: To develop a method of viscodissection involving staining of epiretinal membranes, and to evaluate its efficacy and safety in surgical treatment of proliferative diabetic retinopathy (PDR). MATERIAL AND METHODS: The study included 30 patients with type 1 diabetes mellitus and PDR with tractional retinal detachment (TRD). All patients were divided into two groups. In the first (main) group, at the initial stages of the operation, viscodissection with staining of epiretinal structures was performed, followed by segmentation and removal of membranes; in the second (control) group, segmentation and removal of membranes was performed using a vitreotome and endovitreal forceps. RESULTS: During the follow-up, all patients showed positive trends of morphological and functional indicators. While the number of intraoperative stages was the same in both groups, the total operation time in patients of the main group was significantly lower (p≤0.001) than in patients of the control group (main - 41.3±2.8 min; control - 53.8±6.2 min). With equal number of posterior hyaloid membrane to inner limiting membrane (PHM to ILM) fixation points in both groups, iatrogenic retinal rupture occurred significantly less frequently in patients of the main group (main - 0.6±0.7, control - 3.1±2.9) (p≤0.001). In this regard, among the patients of the control group, in the overwhelming majority of cases, it was necessary to use a silicone oil tamponade (60%) or gas-air mixture (33%), while in the first group the main postoperative media were sterile BSS solution (73%) and gas-air mixture (27%).

[Modern understanding of structural and biochemical characteristics of the vitreous in eyes with normal and increased axial length]. / Sovremennye predstavleniya o strukturnykh i biokhimicheskikh svoistvakh steklovidnogo tela v norme i pri uvelichenii aksial'noi dliny glaza.

The review highlights the features of molecular, morphological and anatomical organization of the vitreous body in normal human eyes and in eyes with elongated anterior-posterior axis. The molecular structure of the vitreous consists of various types of collagen, glycosaminoglycans, glycoproteins and proteoglycans. The lowest concentration of collagen fibrils is in the central vitreous, so the structural changes of vitreous gel associated with attenuation of the vitreous body happen there much earlier and to a greater degree. Increased aggregation of collagen fibrils with age casuses an increase of liquid fractions of the vitreous with a concomitant decrease in gel volume. Similar processes occur earlier in eyes with axial myopia. Destructive processes in myopia increase progressively with axial elongation. As a result of vitreous collapse, vitreoretinal adhesion weakens and posterior vitreous detachment occurs.

[Neurodegenerative biomarkers of the response to diabetic macular edema treatment]. / Neirodegenerativnye biomarkery otveta na terapiyu diabeticheskogo makulyarnogo oteka.

There are currently no reliable biomarkers for predicting the response to treatment of diabetic macula edema (DME). PURPOSE: To asses the predictive role of neurodegenerative biomarker of the response to anti-VEGF therapy of DME. MATERIAL AND METHODS: Examination and treatment was carried out on 14 patients (20 eyes) with DME. The eyes were divided into 2 groups by the type of diabetes: 6 eyes with type 1 diabetes and 14 eyes with type 2 diabetes. The duration of diabetes was 16.5±7.9 years, the level of glycated hemoglobin was 8.4±2%. A number of indicators were evaluated using optical coherence tomography (OCT) in order to determine the neurodegenerative biomarkers of the response to anti-VEGF treatment. All patients underwent standard loading course of Aflibercept (5 intravitreal injections). RESULTS: Significant improvement in Best Corrected Visual Acuity (BCVA) and decrease of central retinal thickness (CRT) was seen after the treatment course. Data analysis revealed a correlation between functional outcomes of the treatment, and the following pathological changes in the retina: thickness of retinal nerve fiber layer (RNFL), thickness of the complex of ganglion cell and inner plexiform layers in the macular region (GCL+), thickness of the RNFL and GCL+ complex (GCL++) in the macular region, ΔCRT, as well as BCVA, patient age, and type of diabetes. Anatomical outcomes correlate with the stage of diabetic retinopathy, RNFL, GCL+, GCL++, violation of the integrity of the ellipsoid zone before treatment. CONCLUSION: The course of intravitreal administration of the Aflibercept drug has been established to be an effective method of treating patients with clinically significant DME. Neurodegenerative biomarkers of the response to the anti-VEGF drug therapy have been determined: thickness of the peripapillary RNFL, GCL+ and GCL ++, as well as integrity of the ellipsoid zone.

[Current possibilities in visualization of retinal periphery in diabetic retinopathy]. / Sovremennye vozmozhnosti vizualizatsii perifericheskikh otdelov setchatki pri diabeticheskoi retinopatii.

Diabetic retinopathy (DR) is an important, socially significant complication of diabetes mellitus that leads to irreversible loss of vision. This article reviews the studies of peripheral changes in DR, different methods used in its diagnostics, monitoring and assessment of therapeutic effects. The article contains detailed examination of the modern widefield imaging methods that allow studying the middle and extreme periphery of the retina and help obtain a wide range of DR biomarkers. Of greatest interest in this matter is optical coherence tomography angiography due to possibility of detailed non-invasive assessment of the condition of retinal microvasculature, precise determination of the area and visualization of the sites of neovascularization and non-perfused regions of the retina. Quantitative characteristics of these changes serve as important diagnostic and prognostic visual biomarkers of DR.

[Current trends in the screening for diabetic retinopathy]. / Sovremennye tendentsii skrininga diabeticheskoi retinopatii.

The incidence of diabetes in the world is steadily increasing, and so is growing the number of cases of vision loss and blindness resulting from diabetic retinopathy (DR). This pathology is asymptomatic in the initial stages, but only the early treatment can be effective. In this regard, DR screening is an important and actual problem. This article reviews the principles, criteria, and problems of the currently run DR screening programs that are based on digital photography of the fundus. Special attention is paid to the displayed biomarkers and their role in DR screening. Various research methods are described, such as fluorescence angiography, optical coherence tomography, optical coherence tomography agniography, laser scanning ophthalmoscopy, which can be used to visualize pathological changes in the retina associated with DR. These changes were considered as potential screening biomarkers for DR. The review also describes new areas of screening based on telemedicine, artificial intelligence, and mobile photo-registering devices.

[Biomarkers of diabetic retinopathy on optical coherence tomography angiography]. / Biomarkery diabeticheskoi retinopatii, poluchennye pri pomoshchi opticheskoi kogerentnoi tomografii v rezhime angiografii.

Pathogenesis of diabetic retinopathy (DR) is complex and multifactorial, giving rise to a wide range of potential biomarkers - quantitatively and objectively measurable indicators of the biological, pathological processes or pharmacological response to therapy. This non-systemic review is devoted to a vital problem - possibility of using biomarkers acquired with optical coherence tomography angiography (OCTA-biomarkers) in DR. The review examines the qualitative and quantitative indicators obtained using OCTA as potential biomarkers of DR. Of greatest interest is the assessment of diabetic microvascular abnormalities such as microaneurysms, intraretinal microvascular abnormalities, neovascularization and non-perfusion (ischemia) zones. A separate section is devoted to currently well-studied indices reflecting the area and regularity of the foveolar avascular zone, and microcirculation indices such as capillary perfusion density, blood flow indices, fractal dimension of retinal microcirculation vessels, etc. The relationship of OCTA-biomarkers and diabetic macular edema is also discussed. Biomarkers obtained with wide-field OCTA, such as indices quantitatively reflecting ischemia and neovascularization are paid special attention in the review. The problems and solutions associated with the use of OCTA-biomarkers in DR are also considered. In general OCTA-biomarkers in DR are becoming an important tool for screening, diagnosis, monitoring of DR, and for predicting and preventing patients' clinical response to treatment.

[The role of internal limiting membrane peeling in the treatment of diabetic macular edema]. / Rol' pilinga vnutrennei pogranichnoi membrany setchatki v lechenii diabeticheskogo makulyarnogo oteka.

Analysis of the current understanding of the role of internal limiting membrane in the pathogenesis of diabetic macular edema and the feasibility of its surgical removal is based on data from domestic and international literature on pathogenesis, clinical manifestations, outcomes of multicenter studies of treatment and prognosis of this disease. The advantages and disadvantages of both peeling and preservation of the inner limiting membrane are described. The limitations and inconsistencies of data provided by the authors of each theory requires more complete functional studies in the pre- and postoperative periods, increasing the selection of patients, modifying the criteria for inclusion in groups, and microscopic examination of removed membranes. Thus, this issue requires further study due to the ambiguity of the conclusions and the lack of comparative data on the long-term prospects of each of the methods.

[On classification of diabetic retinopathy]. / K voprosu o klassifikatsii diabeticheskoi retinopatii.

The article analyses current state of the problem of diabetic retinopathy classifications based on the data from Russian and foreign literature on pathogenesis, clinical manifestations, results of multicenter studies on treatment and prognosis of the disease. Every existing classification was found to be limited in applications; attempts had been made to unify and complement them with the aim of achieving more complete and better-detailed description of the processes of diagnostics and determination of treatment algorithms. In conclusion, none of the existing classifications can be considered consistent in both clinical and practical aspects with respect to diabetic retinopathy.

[Modern approaches to predicting the development of active type 1 retinopathy of prematurity]. / Sovremennye podkhody k prognozirovaniiu aktivnoi retinopatii nedonoshennykh (1-i tip).

PURPOSE: To develop a mathematical model for predicting the development of threshold stages (type 1) of active retinopathy of prematurity (ROP) based on neonatal risk factors in premature infants. MATERIAL AND METHODS: The study observed 69 premature infants from a perinatal center with gestation age of 22-31 weeks and birth weight of 499-1500 grams. Patients were divided into 2 groups depending on the type of ROP: the main group - 40 infants with a threshold stage (type 1) of ROP, requiring laser treatment; the control group - 29 children with spontaneous regression of the initial (1-2) stages (type 2) of the disease. A model for predicting the development of ROP threshold stage was built using mathematical justification. RESULTS: The study established potential predictors of type 1 ROP: staying in the intensive care unit for more than 30 days (p=0.011); duration of child's staying on mechanical ventilator more than 30 days (p=0.002); parenteral nutrition for more than 13 days (p=0.013); presence of respiratory distress syndrome of 3rd degree (p<0.001); presence of bronchopulmonary dysplasia (p=0.034). These predictors were used to design a mathematical model for predicting the development of threshold stages of ROP. CONCLUSION: The proposed prognostic model of type 1 active ROP is characterized by high information content and can be recommended for use in clinical practice of neonatal medical institutions.