Allele-specific PCR with fluorescently labeled probes: criteria for selecting primers for genotyping.

Single-nucleotide polymorphisms (SNPs) can serve as reliable markers in genetic engineering, selection, screening examinations, and other fields of science, medicine, and manufacturing. Whole-genome sequencing and genotyping by sequencing can detect SNPs with high specificity and identify novel variants. Nonetheless, in situations where the interest of researchers is individual specific loci, these methods become redundant, and their cost, the proportion of false positive and false negative results, and labor costs for sample preparation and analysis do not justify their use. Accordingly, accurate and rapid methods for genotyping individual alleles are still in demand, especially for verification of candidate polymorphisms in analyses of association with a given phenotype. One of these techniques is genotyping using TaqMan allele-specific probes (TaqMan dual labeled probes). The method consists of real-time PCR with a pair of primers and two oligonucleotide probes that are complementary to a sequence near a given locus in such a way that one probe is complementary to the wild-type allele, and the other to a mutant one. Advantages of this approach are its specificity, sensitivity, low cost, and quick results. It makes it possible to distinguish alleles in a genome with high accuracy without additional manipulations with DNA samples or PCR products; hence the popularity of this method in genetic association studies in molecular genetics and medicine. Due to advancements in technologies for the synthesis of oligonucleotides and improvements in techniques for designing primers and probes, we can expect expansion of the possibilities of this approach in terms of the diagnosis of hereditary diseases. In this article, we discuss in detail basic principles of the method, the processes that influence the result of genotyping, criteria for selecting optimal primers and probes, and the use of locked nucleic acid modifications in oligonucleotides as well as provide a protocol for the selection of primers and probes and for PCR by means of rs11121704 as an example. We hope that the presented protocol will allow research groups to independently design their own effective assays for testing for polymorphisms of interest.

[Optical coherence tomography in the diagnosis of multiple sclerosis]. / Opticheskaya kogerentnaya tomografiya v diagnostike rasseyannogo skleroza.

Multiple sclerosis (MS) is a chronic autoimmune-inflammatory and neurodegenerative disease. PURPOSE: This study explores the main structural changes in patients with MS and their relationships with the activity and type of disease course. MATERIAL AND METHODS: This prospective study included 159 patients (318 eyes) with an established diagnosis of MS: group (44 eyes; 13.84%) - relapsing-remitting type MS (RRMS) lasting up to 1 year without a history of optic neuritis (ON); group 2 (30 eyes; 9.43%) - RRMS up to 1 year with ON; group 3 (56 eyes; 17.61%) - RRMS lasting from 1 to 10 years without ON; group 4 (38 eyes; 11.95%) - RRMS from 1 to 10 years with ON; group 5 (49 eyes; 15.41%) - RRMS >10 years without ON; group 6 (37 eyes; 11.63%) - RRMS >10 years with ON; group 7 (34 eyes; 10.69%) - secondary progressive multiple sclerosis (SPMS) without ON; group 8 (30 eyes; 9.43%) - SPMS with ON. Patients underwent standard ophthalmological examinations, including optical coherence tomography. RESULTS: A decrease in structural parameters was diagnosed, progressing with the duration of the disease and the presence of ON: the minimum values of mGCL+IPL (65.83±9.14 µm) and mSNFL (76.37±14.77 µm) were detected in the group with SPMS with ON. High inverse correlations of EDSS with mGCL+IPL and mRNFL were demonstrated, with maximum in the group with the longest duration of MS without ON (-0.48 and -0.52 (p=0.01), respectively). CONCLUSION: Changes in the thickness of the structural parameters of the retina, measured by OCT, can be considered as a predictor of the course of MS.

[Optical coherence tomography angiography in the diagnosis of multiple sclerosis]. / Opticheskaya kogerentnaya tomografiya-angiografiya v diagnostike rasseyannogo skleroza.

PURPOSE: This study analyzes the main changes in retinal microcirculation in patients with multiple sclerosis (MS) and their relationship with the type of disease course. MATERIAL AND METHODS: 159 patients (318 eyes) were examined. The groups were formed according to the type of course and duration of MS: group 1 - 37 patients (74 eyes; 23.27%) with relapsing-remitting MS (RRMS) less than 1 year; group 2 - 47 patients (94 eyes; 29.56%) with RRMS from 1 year to 10 years; group 3 - 44 patients (86 eyes; 27.05%) with RRMS >10 years; group 4 - 32 patients (64 eyes; 20.12%) with secondary progressive MS (SPMS). Subgroups A and B were allocated within each group depending on the absence or presence of optic neuritis (ON). Patients underwent standard ophthalmological examination, including optical coherence tomography angiography (OCTA). RESULTS: A decrease in the vessel density (wiVD) and perfusion density (wiPD) in the macular and peripapillary regions was revealed, progressing with the duration of the disease and with its transition to the progressive type. The minimum values were observed in patients with SPMS (group 4), with the most pronounced in the subgroup with ON (wiVD = 16.06±3.65 mm/mm2, wiPD = 39.38±9.46%, ppwiPD = 44.06±3.09%, ppwiF = 0.41±0.05). CONCLUSION: OCTA provides the ability to detect subclinical vascular changes and can be considered a comprehensive, reliable method for early diagnosis and monitoring of MS progression.

[Three-year follow-up study of clinical effectiveness of antiangiogenic therapy for neovascular age-related macular degeneration]. / Klinicheskaya effektivnost' antiangiogennoi terapii neovaskulyarnoi vozrastnoi makulyarnoi degeneratsii po rezul'tatam trekhletnego nablyudeniya.

PURPOSE: The study analyzes long-term (three years) clinical effectiveness of anti-VEGF treatment of neovascular age-related macular degeneration (nAMD) and attempts to identify the most clinically significant associations between the functional and structural parameters. MATERIAL AND METHODS: The study included 122 patients (122 eyes) diagnosed with nAMD, mean age -73.4±6.6 years old. Prospective follow-up lasted 144 weeks. All patients were treated with angiogenesis inhibitor (aflibercept 2 mg), and most of them (72.9%) - according to the Treat-and-Extend protocol. RESULTS: The average number of injections was 7.39±1.28, 4.63±0.97 and 4.06±0.81 during the first, second and third years of the follow-up, respectively. The mean baseline best-corrected visual acuity (BCVA) was 0.24±0.21. After three loading doses, BCVA increased to 0.33±0.26 (+0.09; 37.5%), by the end of follow-up BCVA was 0.35±0.27 (+0.11; 45.8%). Central retinal thickness (CRT) decreased from 314.89±88.07 µm to 234.4±42.8 µm (a 25.5% decrease) by the end of the follow-up. After three loading injections baseline functional and anatomical parameters had the most significant correlations (r≥0.7, p<0.05) with intraretinal fluid, ellipsoid zone integrity and the area of macular atrophy. CONCLUSIONS: Analysis of the morphological and functional outcomes by the end of the first year demonstrates the feasibility of preserving the results while reducing the number of visits and injections according to the Treat-and-Extend protocol. Achieving maximum improvement of functional parameters most significantly correlated with changes in such biomarkers as central retinal thickness, area of macular atrophy and integrity of the ellipsoid zone.

[Diagnosis and clinical features of non-exudative macular neovascularization]. / Diagnostika i klinicheskie osobennosti neekssudativnoi makulyarnoi neovaskulyarizatsii.

Macular neovascularization (MNV) is the process of new abnormal blood vessels formation in the choroid and/or retina. The widespread adoption of optical coherence tomography angiography (OCTA) has significantly expanded the possibilities of not only detecting pathological blood flow before the development of exudation and deterioration of visual acuity, but also determining its characteristics. The purpose of this review is to substantiate the criteria for choosing terminology and diagnostic markers of MNV. The term "non-exudative MNV" refers to type 1 neovascularization without intraretinal or subretinal exudation detected on repeated OCT scans in the course of at least 6 months. This type of MNV may include previously untreated, non-exudative membranes with a low tendency to exudate, as well as previously treated membranes that have become inactive or dormant and no longer require anti-angiogenic therapy. The criterion for dividing the non-exudative form of MNV into inactive (with a low growth rate and vascular density (VD) at baseline) and subclinical (with a high growth rate and VD) is the time of its activation, generally recognized as 6 months. The diagnostic criteria is the visualized "double layer" sign on OCT scans (retinal pigment epithelium and Bruch's membrane), as well as patterns of neovascular membranes of varying sizes, morphology and localization on OCTA scans. The cumulative risk of conversion from subclinical to exudative at two years of follow-up is 13.6 times higher than in eyes without detectable neovascularization, which highlights the importance of frequent monitoring in this healthy eye population for early detection of MNV signs.

[Prognosis criteria of optical coherence tomography angiography for the long-term efficacy of anti-VEGF therapy of neovascular age-related macular degeneration]. / Prognosticheskie kriterii opticheskoi kogerentnoi tomografii-angiografii v otsenke dolgosrochnoi effektivnosti anti-VEGF-terapii neovaskulyarnoi vozrastnoi makulyarnoi degeneratsii setchatki.

PURPOSE: The study aimed to determine the most significant optical coherence tomography angiography (OCTA) parameters in terms of predicting anti-VEGF therapy effectiveness during long-term (3-year) follow-up of patients with neovascular age-related macular degeneration (nAMD). MATERIAL AND METHODS: The study included 122 patients (122 eyes) with mean age of 73.4±6.6 years who were diagnosed with nAMD. Subgroup analysis included 50 patients (50 eyes) with detailed OCT angiography examination of macular neovascularization (MNV) characteristics and their changes in the course of the follow-up, which lasted 144 weeks. All patients were treated by angiogenesis inhibitor (aflibercept 2 mg), most of them - according to Treat-and-Extend protocol. RESULTS: Treatment response (either 'good' or 'partial') was achieved in all patients, and the proportion of the response types was similar in both types 1 and 2 MNV. Key OCTA parameters associated with the number of injections, as well as morphological and functional response (best-corrected visual acuity, retinal neuroepithelium and pigment epithelium detachment), were vascular network area and MNV area assessed at baseline and three months after treatment initiation. Both of these parameters were closely related in both MNV types during the follow-up. Key parameter with maximum number of clinically significant correlations ('very high' strength, p<0.05) in eyes with 'good' response was MNV area, in eyes with 'partial' response - vascular density and greatest vascular caliber. CONCLUSIONS: Vascular network area and MNV area assessed at baseline and after three loading doses were determined as the most significant OCTA characteristics for predicting the number of injections and treatment response based on functional and morphological parameters. MNV area was found to be the most clinically significant marker in 'good' response, vascular density and greatest vascular caliber - in 'partial' response.

[Choroidal microvascular dropout as a biomarker of glaucoma progression in patients with diabetes mellitus]. / Mikrososudistye narusheniya khorioidei kak biomarker progressirovaniya glaukomy pri sakharnom diabete.

PURPOSE: To study the occurrence, features of the development of choroidal microvascular dropout (CMvD) as a possible marker of the severity of the glaucoma process and to assess the impact of diabetes mellitus (DM) on the progression of these changes. MATERIAL AND METHODS: The study included 258 eyes (258 patients), which were divided into groups: 1st - 58 patients (58 eyes) with stage I POAG and DM; 2nd - 50 patients (50 eyes) with stage I POAG; 3rd - 50 patients (50 eyes) with stage III POAG and DM; 4th - 50 patients (50 eyes) with stage III POAG; 5th - 50 patients (50 eyes) with DM. The observation period lasted 24 months. The occurrence and dynamics of the development of CMvD, their relationship with structural and functional indicators of the optic disc in the course of observation were evaluated in patients with POAG and DM. RESULTS: CMvD was detected in stage I POAG in 17 eyes (34%), in patients with DM - in 27 eyes (54%), in the combined course of stage I POAG and DM - in 46 eyes (79.31%), in patients with stage III glaucoma - in 100% of cases. In patients with stage III glaucoma, the CMvD area indicators exceeded the values in other groups and practically did not differ regardless the presence of DM (0.59±0.13 mm2, p=0.005) and its absence (0.57±0.14 mm2, p=0.005). In the first year of follow-up, the increase in the area size of microvascular disorders in patients with POAG I was 5.88%, in comorbid patients - 3.84%, but by the end of the follow-up it increased by 19.23%, and in the group of patients with a high rate of progression - by 31.25%. Strong reliable correlations of CMvD with mean deviation (r=0.89) were revealed, as well as moderate correlations - with structural indicators of the optic disc (r=0.59) and with hemodynamic indicators (r=0.54 and r=0.52). CONCLUSION: Development of CMvD is both a result of glaucomatous damage to the optic nerve and a consequence of a disruption of its hemodynamics at the level of the deep capillary plexus. The results of the study demonstrate the adverse effect of DM on the course of glaucoma, which determines the initiation of microvascular disorders that aggravate the severity of the glaucoma process and the rate of its progression.

[Features of structural and microvascular changes of the choroid in angioretinopathy of various etiologies]. / Osobennosti strukturnykh i mikrovaskulyarnykh izmenenii khorioidei pri angioretinopatii razlichnoi etiologii.

PURPOSE: To study structural and microvascular changes in the choroid in patients with chronic kidney disease (CKD), diabetic retinopathy (DR) and arterial hypertension (AH), and their relationship with the level of renal function, carbohydrate metabolism and blood pressure. MATERIAL AND METHODS: The study involved 172 patients (325 eyes): 56 patients with CKD (109 eyes); 66 patients with DR (121 eyes); 50 patients with AH (95 eyes). All patients underwent comprehensive ophthalmological examination including visometry, biomicroscopy, ophthalmoscopy, optical coherence tomography (OCT) and OCT angiography. RESULTS: In patients with DR and CKD, a decrease in the thickness of the ganglion cell complex and the inner plexiform layer (GCL+IPL) was noted: in proliferative DR (PDR) - 62.45±4.25 µm, in stage 4-5 CKD - 75.23±6.43 µm; a decrease in choroidal thickness (CT) of minimal values in stage 4-5 CKD (179.9±37.72 µm) and PDR (211.0±40.7 µm). The decrease in choroidal vascularity index (CVI) depended on the stage of CKD and PDR (in PDR - 63.47±1.37, in stage 4-5 CKD - 65.93±2.01). Maximum decrease in perfusion density and vascular density was found in patients with DR (37.22±9.00% and 15.11±3.39 mm, respectively). An increase in the area, perimeter of the foveolar avascular zone (FAZ), and a decrease in the circularity index were noted in all groups, with most pronounced changes in PDR and stage 4-5 CKD. Patients with CKD were found to have strong correlations of CT and CVI with creatinine, urea, proteinuria and glomerular filtration rate (GFR). Patients with diabetes mellitus and PDR were revealed to have strong relations of CT, CVI, GCL+IPL, the area and perimeter of FAZ with creatinine levels and the duration of diabetes mellitus. CONCLUSION: Choroidal thickness and choroidal vascularity index are important diagnostic markers of disorders of chorioretinal microcirculation that allow stratifying individual assessment of risk factors for progression of both chronic kidney disease and diabetic retinopathy.

[New findings on pathogenetic mechanisms in the development of age-related macular degeneration]. / Novye dannye o patogeneticheskikh mekhanizmakh razvitiya vozrastnoi makulyarnoi degeneratsii.

Age-related macular degeneration (AMD) is a complex multifactorial disease that occurs due to disfunction and degeneration of retinal pigment epithelium (RPE) and choriocapillaris, as well as death of photoreceptors. The exact pathogenetic mechanism remains uncertain. The aging process is the main and the clearest risk factor of AMD. In the development of this condition, a special role belongs to the secretory phenotype of aging spreading from one cell to another and mediated by the secretion and release of growth factors, cytokines, chemokines, proteases, and other molecules. Another major contributor is oxidative stress caused by violations in the recirculation of vitamin A in the vision cycle and accompanied by accumulation of lipofuscin, which mediates the formation of iron-based oxidants that are toxic for mitochondria. Furthermore, prolonged oxidative stress and constant light exposure induce the development of inflammation in the retina. Accumulation of metabolic products and cellular defects with age can induce an inflammatory reaction that amplifies the damage. The inflammatory processes including innate immune response, activation of microglia and parainflammation that occur locally in the vascular membrane, pigment epithelium and neuroretina are very significant contributors to the age-related changes, their progression, and the development of advanced stages of AMD. Various growth factors play a special role in the development of choroidal neovascularization (CNV). Vascular endothelial growth factor A (VEGF-A) has traditionally been considered the main factor of neoangiogenesis and, consequently, the main therapeutic target, but in recent years various studies have determined the role of other factors - VEGF-B, C, D, PGF, Gal-1, angiopoietins. This article describes the main underlying mechanisms in the development of choroidal neovascularization including retinal aging, impaired metabolic activity, mitochondrial dysfunction, inflammatory reactions and genetic variations, as well as the role of various growth factors.

[Structural and microvascular changes in the retina and choroid in patients with chronic kidney disease]. / Osobennosti strukturnykh i mikrovaskulyarnykh izmenenii setchatki i khorioidei pri khronicheskoi bolezni pochek.

PURPOSE: To study the main structural and microvascular changes in the retina and choroid in patients with diabetic retinopathy (DR) and chronic kidney disease (CKD), and their relationship with impaired renal function. MATERIAL AND METHODS: The study included 158 patients (304 eyes). The 1st group consisted of 50 patients with CKD (97 eyes); group 2 - 65 patients with DR (119 eyes), group 3 - 43 patients with CKD and DR (86 eyes). All study patients underwent complete ophthalmological examination, including optical coherence tomography (OCT) and OCT angiography (OCTA) of the macular region. RESULTS: The analysis of structural parameters in groups of patients showed a decrease in the thickness of the ganglion cell layer and the inner plexiform layer of the retina in patients with DR (70.85±14.49 µm), with the lowest value in the CKD+DR group (65.84±15.34 µm) in comparison with the CKD group (75.64±10.32 µm). In the groups of patients with CKD, the thickness of the choroid (207.3±40.36 µm) was significantly reduced in comparison with the group of patients with DR (258.8±26.63 µm) and correlated with the stage of the disease. Patients in the CKD+DR group had the lowest perfusion and vascular density in the macular region (31.23±10.91% and 13.15±2.73 mm), an increase in the area and perimeter of the foveal avascular zone (0.55±0.26 mm2, 3.30±0.84 mm). Pronounced correlations of decrease in choroidal thickness, vascular density, and perfusion volume with low glomerular filtration rate and CKD stage, as well as urea and creatinine levels were determined. An increase in the area of the foveal avascular zone correlated with lower retinal capillary density, decreased perfusion volume, and the stage of both DR and CKD. CONCLUSION: Structural and hemodynamic disorders of the retina and choroid can be recognized as significant biomarkers for non-invasive diagnosis of microvascular complications of diabetes mellitus and impaired renal function.

[Optical coherence tomography angiography in the diagnosis of retinal microvascular changes in chronic kidney disease (clinical observations)]. / Opticheskaya kogerentnaya tomografiya-angiografiya v diagnostike mikrovaskulyarnykh izmenenii setchatki pri khronicheskoi bolezni pochek (klinicheskie nablyudeniya).

One distinctive pathological sign of chronic kidney disease (CKD) is microcirculatory disorders, which mark it as a microvascular disease. Similarity in the blood supply of the retina and kidneys, in the anatomy of their vascularization lead to identical complications in these organs. The retinal-choroidal microvascular system is easily accessible for clinical and morphological assessment and can be examined by the reproducible and non-invasive method - optical coherence tomography (OCT) and OCT angiography (OCTA). The study of significant diagnostic tomographic retinal biomarkers in CKD and monitoring of their changes are of great clinical importance. The article presents clinical cases of changes in the retina and choroid depending of the stage of CKD. Retinal microvascular changes precede functional impairment. A significant decrease in retinal and choroidal thickness correlates with a decrease in the glomerular filtration rate (GFR) and the degree of albumin excretion in the urine. All clinical cases were observed to exhibit retinal microcirculation disorders, capillary rarefaction in both capillary plexuses accompanied by a decrease in vessel density and a decrease in the circularity index of the foveal avascular zone as a result of regression of the parafoveal capillary networks. OCTA allowed visualization of morphological changes at the microcirculatory level in the form of blunt ends of capillaries, their increased tortuosity and the presence of local areas of decreased perfusion. The severity of retinal microvascular changes varied depending on the stage of CKD and was not associated with either age or the presence of diabetes mellitus. Assessment of the retinal microvasculature can help with monitoring of microvascular lesions, early prediction of the risk of development and progression of decreased renal function, as well as allow avoiding aggressive diagnostic biopsy.

[Ophthalmic safety profile of antiangiogenic therapy]. / Profil' oftal'mologicheskoi bezopasnosti antiangiogennoi terapii.

Antiangiogenic therapy with inhibitors of vascular endothelial growth factor (anti-VEGF) has not only fundamentally changed the treatment outcomes of vasoproliferative eye diseases, but also became the most common ophthalmic surgical manipulation. At the same time, in 36-48% of bilateral lesions there is a need to perform injections in both eyes, making relevant the issues of safety and prevention of severe complications that threaten irreversible loss of visual function. The article reviews the results of randomized clinical trials and real clinical practice, analyzes the incidence and causes of its most dangerous complication - endophthalmitis, characterizes the clinical course depending on the type of drug used, and considers the possibility of reducing the risk of this complication occurring. Special attention is paid to the safety profile of a new VEGF inhibitor - brolucizumab - which has received registration for the treatment of neovascular age-related macular degeneration (nAMD). Specialists dealing with retinal pathologies acknowledge the need to monitor the state of the anterior and posterior parts of the eye in order to detect the signs of intraocular inflammation as quickly and early as possible. Drug efficacy, treatment regimen, duration of action and safety are the main characteristics that should determine the personalized approach in each clinical case.

[Development, clinical manifestations and diagnosis of retinal changes in chronic kidney disease]. / Osobennosti razvitiya, klinicheskie proyavleniya i diagnostika izmenenii setchatki pri khronicheskoi bolezni pochek.

Chronic kidney disease (CKD) is a significant public health problem with a high risk of developing age-dependent eye diseases. Renal glomeruli and the choroid have similar structures and vascular networks; the internal hematoretinal barrier and the glomerular filtration barrier have similar developmental path; the renin-angiotensin-aldosterone hormonal system is found in both the eye and the kidneys. All this determines the similarity of physiological and pathogenetic features of the development of diseases associated with these organs. The article discusses general risk factors and pathophysiological mechanisms of development of retinal and renal lesions in CKD, the influence of various factors of pathogenesis on their development and progression. The anatomical similarity of vascularization, accompanied by microvascular changes in the retina and kidneys, leads to similar complications in both organs. Optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A) are accurate, well reproducible and non-invasive methods for diagnosing and assessing changes in the retinal microvascular bed, which make it possible to assess microvasculature changes in the kidneys. In CKD, the retina shows signs of impaired capillary perfusion, a decrease in their density, expansion of intercapillary spaces, a rarefaction of the density of the parafoveolar capillary network, which may indicate a decrease in peritubular capillary blood flow, blood circulation of the kidneys in general and their ischemia. Significant thinning of the retina and choroid, along with a decrease in macular volume, even in the initial stages of CKD, is accompanied by impaired renal function (changes in the estimated glomerular filtration rate and urinary albumin excretion), which is a sign of systemic microvascular lesion and pathological process in the kidneys. Therefore, monitoring of retinal vessels using OCT and OCT-A can become a reliable indicator of the progression of renal microvascular changes at any stage of the disease.

[Anti-angiogenesis therapy of diabetic macular edema in patients with primary open-angle glaucoma]. / Antiangiogennaya terapiya diabeticheskogo makulyarnogo oteka u patsientov s pervichnoi otkrytougol'noi glaukomoi.

Despite the high clinical effectiveness and widespread introduction of anti-angiogenesis (anti-VEGF) therapy into practice, its long-term effect on the development of structural changes in the treatment of primary open-angle glaucoma (POAG) patients with diabetic macular edema (DME) hasn't been studied sufficiently and so presents certain interest. PURPOSE: To study the effect of anti-VEGF therapy on the structural and functional state of the retina and optic nerve in patients with DME and POAG. MATERIAL AND METHODS: The study included 72 patients (132 eyes): the 1st group - 22 patients (40 eyes) with stage I POAG and DME, the 2nd group - 25 patients (46 eyes) with DME receiving anti-VEGF therapy. The 3rd group (control) consisted of 25 patients (46 eyes) with stage I POAG. The observation period lasted 24 months. The average number of injections was 8.48±3.65. The indicators for evaluation were: visual acuity, tonometry, perimetry, optical coherence tomography (OCT) of the optic nerve and macular region. RESULTS: By the end of the observation period, the increase in IOP in the groups was +0.82 (4.4%), 0.41 (2.4%), 0.65 (3.6%) mm Hg. In the group of comorbid patients, a small-scale increase trend of BCVA was noted: +0.05 (6.6%), a decrease in MD by -2.48 Db (92.1%), an increase in excavation volume by 0.16 (43.2%) mm3, decrease in the area of RA by 0.3 mm2 (12.7%). A decrease in retinal nerve fibers layer (RNFL) thickness of 6.55 µm (7.8%), mainly the superior (9.2%), inferior (7.3%) and nasal sectors (7.9%). Loss of GCL+IPL 8.68 µm (12.7%) in the superior (19%), superonasal (20.2%) and inferonasal (20.7%) sectors. CONCLUSION: The combined course of POAG and DME is accompanied by a decrease in the functional and structural parameters of the retina and optic nerve, and a higher rate of progression of glaucomatous optic neuropathy. Long-term results did not reveal a significant deterioration in the structural parameters of the optic disc and retina against the background of anti-VEGF therapy when comparing the study groups.

[Different types localisation of retinal fluid as prognostic biomarkers in the choice of anti-VEGF therapy for age-related macular degeneration]. / Rol' razlichnykh tipov lokalizatsii retinal'noi «zhidkosti¼ kak prognosticheskikh biomarkerov v vybore rezhima antiangiogennoi terapii pri vozrastnoi makulyarnoi degeneratsii.

Age-related macular degeneration is an advanced chronic disease and the main cause of vision loss in geriatric patients. Optical coherence tomography (OCT) is a modern method of retinal imaging allowing to detect different types of fluid: intraretinal fluid (IRF), subretinal fluid (SRF) and fluid under pigment epithelial detachment (PED). Finding relevant imaging biomarkers is necessary for identification of basic activity criteria of the disease, choosing treatment algorithms, determining treatment duration and termination criteria, and predicting the outcomes. Presence of IRF is associated with poor functional outcomes. Its presence is an indication for early beginning of treatment aimed at full resorption of the fluid with further possible careful extension of anti-VEGF therapy intervals with a regular follow-up. Degenerative intraretinal cysts developing in the background of subretinal fibrosis in absence of choroidal neovascularization (CNV) should be a sign for discontinuation of anti-VEGF therapy due to the lack of targets. Presence of SRF is associated with favorable outcomes and good treatment prognosis and is not a barrier to the extension of treatment intervals even up to the maximum of 16 weeks as described in existing randomized controlled trials, on the condition of no other CNV activity. PED with active CNV is one of the biomarkers that reveal the need for long-term aggressive therapy. In case of its size gain, it is necessary to restart the anti-VEGF treatment to prevent visual loss in the long-term. Combination of different fluid types is a sign of lasting disease history with a poor outcome prognosis. In this case, anti-VEGF treatment should be started as soon as possible with long-term fixed regimen or Treat-and-extend (T&E) with minimal suitable interval for the patient and precise monitoring of the condition of retina until complete suppression of activity. Developing a personalized approach in each case plays an important role in preserving visual functions.

[Protocol of intravitreal drug delivery. Consensus of the Expert Counsil of Retina and Optic Nerve Diseases of the All-Russian Public Organasation «Association of Ophthalmologists¼]. / Protokol vypolneniya intravitreal'nogo vvedeniya lekarstvennykh preparatov. Konsensus Ekspertnogo soveta po zabolevaniyam setchatki i zritel'nogo nerva Obshcherossiiskoi obshchestvennoi organizatsii «Assotsiatsiya vrachei-oftal'mologov¼.

Intravitreal drug administration is a procedure that has become widespread in modern ophthalmology. However, there is no global consensus on certain aspects of this manipulation, and practitioners feel the need for guidelines. In the Russian Federation, until now, such a document was not available. The expert council on diseases of the retina and optic nerve of All-Russian public organization «Association of Ophthalmologists¼, with participation of invited specialists, has studied and analyzed the existing foreign guidelines for performing intravitreal injections, as well as the regulatory framework in Russia. As a result, this Protocol was developed and approved for use in the healthcare system of the Russian Federation. The document regulates the requirements for specialists and organizations, the conditions for performing the procedure and the necessary material resources and presents an algorithm for performing intravitreal drug administration, a patient examination check-list for various conditions of the procedure, as well as parameters for evaluating and monitoring the quality of the procedure.

[Specific biomarkers of response to antiangiogenic therapy]. / Spetsificheskie biomarkery otveta na antiangiogennuyu terapiyu.

Age-related macular degeneration (AMD) and diabetic macular edema (DME) are the main causes of blindness in the elderly and loss of central vision in patients with diabetic retinopathy, respectively. Anti-VEGF therapy is currently the gold standard for treatment of such patients; it has proved its effectiveness in both randomized clinical trials and clinical practice. However, it should be taken into account that the extent of therapeutic response varies depending on individual characteristics of patients, including the presence of biomarkers that predict the therapeutic response. Numerous studies have discovered a variety of biomarkers for patients with DME and AMD, but their reliability differs and not all of them are eligible for predicting the effectiveness of the treatment. Compared to full clinical examination, biomarkers can offer shorter clinical study duration and lower costs. Most of the specific biomarkers for predicting the response to antiangiogenic therapy are identified using optical coherence tomography. The purpose of this article is to provide contemporary data on the diagnosis and treatment of patients depending on the presence of specific biomarkers.

Autophagy as a Target for the Retinoprotective Effects of the Mitochondria-Targeted Antioxidant SkQ1.

Age-related macular degeneration (AMD) is a complex neurodegenerative disease, a main cause of vision loss in elderly people. The pathogenesis of dry AMD, the most common form of AMD (~ 80% cases), involves degenerative changes in the retinal pigment epithelium (RPE), which are closely associated with the age-associated impairments in autophagy. Reversion of these degenerative changes is considered as a promising approach for the treatment of this incurable disease. The purpose of our study was to assess the relationship between previously identified retinoprotective effects of the mitochondrial antioxidant plastoquinonyl-decyl-triphenylphosphonium (SkQ1) and its influence on the autophagy process in senescence-accelerated OXYS rats characterized by the development of AMD-like retinopathy (Wistar rats were used as a control). The treatment with SkQ1 (250 nmol/kg body weight) during the period of active disease progression (from 12 to 18 months of age) completely prevented progression of clinical manifestations of retinopathy in the OXYS rats, suppressed atrophic changes in the RPE cells and activated autophagy in the retina, which was evidenced by a significant decrease in the content of the multifunctional adapter protein p62/Sqstm1 and increase in the level of the Beclin1 gene mRNA. In general, the results obtained earlier and in the present study have shown that SkQ1 is a promising agent for prevention and suppression of AMD.

VEGF and PEDF levels in the rat retina: effects of aging and AMD-like retinopathy.

Age-related macular degeneration (AMD) is the leading cause of vision loss among the elderly. By clinical signs, there are two forms of AMD: the atrophic or dry (~ 90% of all cases) and wet or neovascular AMD (~10% of cases). Anti-vascular endothelial growth factor (VEGF) intravitreal agents are the only successful treatment for wet AMD. However, there are emerging signals that anti-VEGF treatment can potentially increase development of atrophic AMD. There is neither a treatment of the dry AMD due poor understanding of the pathogenesis and retina aging process in general. We have shown previously that senescence-accelerated OXYS rats are a suitable model of dry AMD. Signs of retinopathy in OXYS rats manifest themselves by age 3 months against the background of a decline in the number of retinal pigment epithelium (RPE) cells and an alteration of choroidal microcirculation. Herein, we compared retinal expression of proteins VEGF and PEDF (pigment epithelium-derived factor) between OXYS and Wistar rats (control). The amount of the VEGF protein increased with age in the retina of both rat strains from 3 months of age. From age 3 to 24 months, this parameter was significantly lower in OXYS rats than in Wistar rats. PEDF protein concentration was significant lower in the OXYS retina only at the age of 3 months. We can conclude that development of retinopathy in OXYS rats takes place at reduced concentrations of VEGF and PEDF. Because RPE cells control the VEGF-PEDF balance, an RPE-targeted approach is a logical choice for AMD treatment and for decreasing adverse effects of anti-VEGF treatment.

[Anti-VEGF therapy for diabetic macular edema. From theory to clinical practice]. / Antiangiogennaia terapiia diabeticheskogo makuliarnogo oteka. Ot teorii k klinicheskoi praktike.

PURPOSE: To evaluate clinical effectiveness of aflibercept therapy for patients with diabetic macular edema (DME) - both naïve to the drug and unresponsive to previous anti-VEGF treatment. MATERIAL AND METHODS: The study included 127 patients (127 eyes) divided into two groups. The first group consisted of 100 primary DME patients (100 eyes) with mean age of 68.48±2.56 years and average disease duration of 12.50±7.85 years. The second group comprised 27 patients (27 eyes) with resistant macular edema who had received three or more 0.5 mg ranibizumab loading injections. Their average age was 66±4.12 and the mean number of previous anti-VEGF injections before changing therapy was 4.56±1.21. The evaluation parameters included Best Corrected Visual Acuity (BCVA) and Central Retinal Thickness (CRT) that were assessed initially and after each 2 mg aflibercept injection (at 1-month intervals during the 6 months of DME therapy). RESULTS: The average number of aflibercept injections in the first group was 4.34±1.22. BCVA improved in 100% of patients of that group after the 3rd injection with resulting mean value of 0.32±0.15. Maximum BCVA improvement was seen after the 6th injection amounting to 0.46±0.2. CRT decreased in 100% of patients of that group after the 1st injection. One month after the therapy start, CRT decreased in average by 17.96% - to 370.89±50.55 µm; at 3 months, CRT was 344.65±48.56 µm; after 6 month - 283.40±49.76 µm. All patients of the second group had retinal morphology restored, visual function improved in 55% of patients. Mean CRT decrease was 180±44 µm, BCVA improvement - 0.13±0.08, mean number of aflibercept injections - 4.86±0.9. CONCLUSION: Aflibercept can be used as first-choice drug for treatment of DME patients (both therapy-naïve and unresponsive to previous ranibizumab therapy) to improve anatomical parameters and visual function.