Preproliferative Diabetic Retinopathy Research Articles

Using artificial intelligence as an initial triage strategy in diabetic retinopathy screening program in China

Objective: To investigate the diagnostic accuracy and efficiency of an artificial intelligence (AI) triaging model in a diabetic retinopathy (DR) screening program. Methods: A DR screening program was conducted in Kashi City and Kizilsu Kirghiz Autonomous Prefecture of the Xinjiang Uyur Autonomous Region from May to July 2018, and 8 005 patients with diabetes mellitus were included. Fundus images, one centered at optic disc and one centered at macula, were taken for both eyes. A previously validated AI algorithm was applied as the first step to identify the patients with all 4 images. If the images were classified as gradable and negative DR, an AI-generated report was immediately provided without sending to manual grading, and 1/3 of these patients were randomly sampled for manual grading and quality control (group A). For the patients with at least one image classified as ungradable or positive for any DR, all images were sent for manual grading (group B). Finally, 300 patients were randomly selected from group A and group B respectively for accuracy assessment, where the patients and their images were classified by a specialist panel for referral DR (pre-proliferative DR, or proliferative DR, and/or diabetic macular edema). Results: Among 8 005 patients for DR screening [including 3 220 males and 4 785 females, aged (58.3±10.6) years], after AI triaging, 5 267 (65.8%) potentially received reports from AI system and 2 738 (34.2%) required manual grading. In group A, the accuracy and specificity of AI classification and manual grading on referral DR were all 100%. In group B, the accuracy of AI and manual grading were 75.8% and 90.3%, respectively, while the sensitivity of AI and manual grading was 100% and 79.1%, respectively. Conclusion: AI alleviates 60% of the workload of manual grading without missing any referral patients with the aid of the current AI triaging model.

Low circulating dihomo-gamma-linolenic acid is associated with diabetic retinopathy: a cross sectional study of KAMOGAWA-DM cohort study

Diabetic retinopathy (DR), one of the major complications of diabetes, can cause blindness and reduce quality of life. Dyslipidemia is reported to be associated with DR, whereas arachidonic acid may have a protective effect against DR. We aimed to investigate the association of circulating n-3 and n-6 polyunsaturated fatty acids (PUFAs) with DR. In this cross-sectional study, 190 Japanese patients with type 2 diabetes were classified as no diabetic retinopathy (NDR), simple diabetic retinopathy (SDR), or proliferative diabetic retinopathy (PDR) including pre-proliferative diabetic retinopathy. Circulating fatty acids (FAs) were measured by gas chromatograph-mass spectrometry. Logistic regression analysis was performed to investigate the association between the levels of FAs and the presence of DR. The average age, body mass index and the duration of diabetes were 62.7 ± 12.1 years, 25.0 ± 4.5 kg/m2, and 9.8 ± 8.7 years, respectively. Twenty-seven patients were diagnosed with DR. Circulating levels of dihomo-gamma-linolenic acid (DGLA) in the NDR (n = 163), SDR (n = 13) and PDR (n = 14) groups were 28.3 ± 11.0 μg/mL, 24.4 ± 9.7 μg/mL, and 21.8 ± 6.2 μg/mL, respectively (p = 0.032). The logarithm of circulating DGLA levels was associated with the presence of DR after adjusting for covariates (OR of 1-unit increment: 0.79, 95% CI: 0.62-1.00, p = 0.049). Circulating DGLA was negatively associated with the presence of DR.

Hyperspectral Ophthalmoscope Images for the Diagnosis of Diabetic Retinopathy Stage.

A methodology that applies hyperspectral imaging (HSI) on ophthalmoscope images to identify diabetic retinopathy (DR) stage is demonstrated. First, an algorithm for HSI image analysis is applied to the average reflectance spectra of simulated arteries and veins in ophthalmoscope images. Second, the average simulated spectra are categorized by using a principal component analysis (PCA) score plot. Third, Beer-Lambert law is applied to calculate vessel oxygen saturation in the ophthalmoscope images, and oxygenation maps are obtained. The average reflectance spectra and PCA results indicate that average reflectance changes with the deterioration of DR. The G-channel gradually decreases because of vascular disease, whereas the R-channel gradually increases with oxygen saturation in the vessels. As DR deteriorates, the oxygen utilization of retinal tissues gradually decreases, and thus oxygen saturation in the veins gradually increases. The sensitivity of diagnosis is based on the severity of retinopathy due to diabetes. Normal, background DR (BDR), pre-proliferative DR (PPDR), and proliferative DR (PDR) are arranged in order of 90.00%, 81.13%, 87.75%, and 93.75%, respectively; the accuracy is 90%, 86%, 86%, 90%, respectively. The F1-scores are 90% (Normal), 83.49% (BDR), 86.86% (PPDR), and 91.83% (PDR), and the accuracy rates are 95%, 91.5%, 93.5%, and 96%, respectively.

Comparison of true-colour wide-field confocal scanner imaging with standard fundus photography for diabetic retinopathy screening

BackgroundScreening of diabetic retinopathy (DR) reduces blindness by early identification of retinopathy. This study compares DR grades derived from a two-field imaging protocol from two imaging platforms, one providing a...

Serum high sensitivity C reactive protein levels in patients with diabetic retinopathy: a cross sectional study

Background: Diabetic retinopathy (DR) is one of the major visual morbidities associated with diabetes. This study determined the levels of serum high-sensitivity C-reactive protein (hs-CRP) in patients with DR and to correlate the estimated levels of serum hs-CRP with the severity of DR and other coexisting factors.Methods: This was a cross-sectional study conducted between March 2009 and August 2010 and included patients with type 2 diabetes mellitus (T2DM) with or without DR. A detailed fundus evaluation was performed using direct and indirect ophthalmoscopy. The retinopathies were observed and documented in accordance with the Kanski's system of classification as background DR (BDR), pre-proliferative DR (PPDR), and proliferative DR (PDR). Laboratory investigations determined the levels of fasting blood glucose (FBG), postprandial blood glucose (PPBG), glycosylated hemoglobin, urine albumin excretion, and serum hs-CRP levels.Results: In total, 80 patients with T2DM were included (DR group, n=40 [BDR, n=22; PDR, n=11; PPDR, n=7]; control group, n=40). Highest serum hs-CRP levels were found in PDR group (6.68 mg/L), followed by PPDR and BDR group (3.2 mg/L and 1.56 mg/L, respectively). The PDR group showed the longest duration of diabetes (16 years), highest FBG (221.8 mg/dL) and HbA1c (6.68 mg/L). The incidence of albuminuria and maculopathy was higher in PDR group (72.7% and 54.54%, respectively). A significant association of hs-CRP levels with DR in patients with T2DM was observed. A significantly (<0.005) positive correlation of hs-CRP was also observed with age, duration of disease, FBG, PPBG, and HbA1c.Conclusions: Patients with severe grades of retinopathy had significantly higher hs-CRP levels than patients with the milder grades.

Frequency of Diabetic Retinopathy in patients with Type-II diabetes mellitus in an upscale clinic in Karachi.

Objectives: The objective of this study is to measure the current frequency of diabetic retinopathy in Karachi and the stage at which they present first to the outpatient department. Study Design: Cross sectional study. Setting: A private clinic setup in Karachi. Period: 1st July 2015 to 30th June 2016. Material & Methods: In this study, 440 eyes of 220 diabetics were included and frequency of diabetic retinopathy was measured. Individuals ranging from 20 – 80 years age were included. Ophthalmic plus systemic relevant history from every patient was taken in detail. Standard Snellen’s chart was used to check the best corrected visual acuity (BCVA). Slit lamp examination was done along with fundoscopy with +90D and +70D lens after dilatation with Tropicamide 1%. All patients were examined for diabetic retinopathy. Along with it, stage of diabetic retinopathy, association of diabetic retinopathy with hypertension, age and duration of diabetes was also taken into consideration. Results: The frequency of diabetic retinopathy amongst 220 patients was found to be 15.9% while 6.6 % of them were also having associated maculopathy. The stages of diabetic retinopathy were found to be 10.4% background diabetic retinopathy(BDR), 0.9% preproliferative diabetic retinopathy(PPDR), 3.4% proliferative diabetic retinopathy(PDR) and 1.1% advance diabetic eye disease(ADED). Overall, 58.5% of the patients also had hypertension along with it. Conclusion: Nationwide studies are needed to be conducted to prevent this complication from progressing while the incidence of diabetic retinopathy is increasing very alarmingly among the society.

Trends in Diabetic Retinopathy, Visual Acuity, and Treatment Outcomes for Patients Living With Diabetes in a Fundus Photograph–Based Diabetic Retinopathy Screening Program in Bangladesh

Diabetic retinopathy (DR) is the leading cause of low vision among working-age adults. An estimated 6.9 million people in Bangladesh were living with diabetes in 2017, which is projected to increase to more than 10 million people in 2025. Currently, no standardized and/or large-scale DR screening program exists in Bangladesh. To develop a novel fundus photograph-based eye screening model for early detection of DR to prevent vision loss in Bangladeshi individuals with diabetes. In this cross-sectional study, 49 264 patients with diabetes underwent opportunistic eye screening at 2 eye hospitals and 1 diabetic hospital in Bangladesh between June 1, 2010, and September 30, 2017. The data set was analyzed from April 8 to December 30, 2018. Technicians were trained to obtain 2-field digital fundus photographs and to grade each according to a standardized DR severity scale. Each patient was counseled and triaged for treatment using defined DR referral criteria. Primary DR grading outcomes, visual acuity, and treatment outcomes. A total of 49 264 patients (54.3% male; mean [SD] age, 50.8 [12.3] years) underwent DR screening during a 7-year period. The DR prevalence rate across all 3 sites was 33% (95% CI, 33%-33%). Prevalence rates varied by center (Chittagong, 64.6% [95% CI, 64.0%-65.0%]; Dhaka, 39.8% [95% CI, 39.0%-41.0%]; and Feni, 13.0% [95% CI, 13.0%-14.0%]). Across all age groups, male patients were at higher risk of prevalent DR than female patients (odds ratio, 1.99; 95% CI, 1.90-2.07). The prevalence was 3.9% for preproliferative DR, 7.8% for proliferative DR, and 19.2% for maculopathy. Individuals with DR had significantly worse visual acuity than those with no DR (best-corrected visual acuity, 0.35 vs 0.21 logMAR; P < .001). The rate of moderate visual impairment was 12.2%, and the rate of blindness was 2.5%. Primary treatments included laser photocoagulation (n = 1637), intravitreal injection (n = 1440), and vitrectomy (n = 309). Screening Bangladeshi individuals known to have diabetes using fundus photography identified large numbers of patients with sight-threatening proliferative DR, maculopathy, and visual impairment or blindness. Expansion of eye screening services in Bangladesh is warranted as part of a national government eye care and diabetes health policy.

Diabetes and Phacoemulsification Cataract Surgery: Difficulties, Risks and Potential Complications.

Diabetes mellitus is one of the most prevalent chronic diseases worldwide. Diabetic patients are at risk of developing cataract and present for surgery at an earlier age than non-diabetics. The aim of this study was to review the problems associated with cataract surgery in a diabetic patient. Corneal complications in diabetic patients include delayed wound healing, risk of developing epithelial defects or recurrent erosions due to the impairment of epithelial basement membranes and epithelial–stromal interactions. Diabetic patients present lower endothelial cell density and their endothelium is more susceptible to trauma associated with cataract surgery. A small pupil is common in diabetic patients making cataract surgery technically challenging. Finally diabetic patients have an increased risk for developing postoperative pseudophakic cystoid macular edema, posterior capsule opacification or endophthalmitis. In patients with pre-proliferative or proliferative diabetic retinopathy, diabetic macular edema or iris neovascularization adjunctive therapy such as an intravitreal anti-vascular endothelial growth factor injection, can inhibit exacerbation related to cataract surgery.

Cotton wool spots detection in diabetic retinopathy based on adaptive thresholding and ant colony optimization coupling support vector machine

Diabetic retinopathy is the major issue of diabetes‐induced blindness worldwide but is curable if detected in time. Cotton wool spots (CWSs) are the critical lesions of diabetic retinopathy, which indicate not only advanced nonproliferative but also preproliferative diabetic retinopathy. It is crucial to detect CWSs for grading the severity of diabetic retinopathy. By grading the severity of diabetic retinopathy accurately, the eye specialist can make an effective treatment plan to protect the patient's vision against blindness. CWSs detection remains challenging because of their uneven appearance, in which some CWSs are not clearly visible and some resemble hard exudates. This paper proposed an automatic CWS detection method based on adaptive thresholding and ant colony optimization (ACO) coupled with support vector machine (SVM). One‐hundred and sixty‐two features from five feature sets, namely morphologies, first‐order statistics, gray‐level co‐occurrence matrix, gray‐level run length matrix, and lacunarity, are extracted, and then four feature selection methods,namely genetic algorithm, particle swarm optimization, stepwise method, and ACO, are coupled with SVM classifiers. The evaluation results of the proposed methods on local, standard diabetic retinopathy database calibration level 1, and high‐resolution fundus image database datasets containing 319 images indicate that ACO coupling cubic SVM performs better than the other pairs with sensitivity 90.16%, specificity 97.92%, accuracy 96.96%, and area under receiver operating characteristic curve 97.19%. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley &amp; Sons, Inc.

An Automated Grading System for Detection of Vision-Threatening Referable Diabetic Retinopathy on the Basis of Color Fundus Photographs.

The goal of this study was to describe the development and validation of an artificial intelligence-based, deep learning algorithm (DLA) for the detection of referable diabetic retinopathy (DR). A DLA using a convolutional neural network was developed for automated detection of vision-threatening referable DR (preproliferative DR or worse, diabetic macular edema, or both). The DLA was tested by using a set of 106,244 nonstereoscopic retinal images. A panel of ophthalmologists graded DR severity in retinal photographs included in the development and internal validation data sets (n = 71,043); a reference standard grading was assigned once three graders achieved consistent grading outcomes. For external validation, we tested our DLA using 35,201 images of 14,520 eyes (904 eyes with any DR; 401 eyes with vision-threatening referable DR) from population-based cohorts of Malays, Caucasian Australians, and Indigenous Australians. Among the 71,043 retinal images in the training and validation data sets, 12,329 showed vision-threatening referable DR. In the internal validation data set, the area under the curve (AUC), sensitivity, and specificity of the DLA for vision-threatening referable DR were 0.989, 97.0%, and 91.4%, respectively. Testing against the independent, multiethnic data set achieved an AUC, sensitivity, and specificity of 0.955, 92.5%, and 98.5%, respectively. Among false-positive cases, 85.6% were due to a misclassification of mild or moderate DR. Undetected intraretinal microvascular abnormalities accounted for 77.3% of all false-negative cases. This artificial intelligence-based DLA can be used with high accuracy in the detection of vision-threatening referable DR in retinal images. This technology offers potential to increase the efficiency and accessibility of DR screening programs.

Short-Term Impact of Bariatric Surgery on Best-Corrected Distance Visual Acuity and Diabetic Retinopathy Progression.

The immediate impact of rapid glucose lowering induced by bariatric surgery on diabetic retinopathy (DR) progression remains unclear. We present 3-year changes in the best-corrected visual acuity and DR grade in a retrospective observational study of 32 morbidly obese patients (64 eyes) who underwent Roux-en-Y-gastric bypass surgery. We found that despite overall benefits in vision, there was an initial progression from no retinopathy to background retinopathy in 18.9% and 21.7% at years 1 and 2 respectively. Patients with pre-proliferative DR at baseline were at increased risk of developing sight-threatening DR. We recommend that patients with diabetes undergoing bariatric surgery have a baseline visual acuity, macular optical coherent tomography and diabetic retinopathy grading from wide-field digital imaging to identify those at risk of sight-threatening diabetic retinopathy.

Male Type 2 Diabetic Patients Have Higher Diabetic Retinopathy Prevalence

Diabetic retinopathy (DR) is one of the main causes of visual loss in individuals aged 20-64 years old. Some evidence indicate clear sex gender differences in diabetes complications, but studies focused on sex-gender differences in DR do not give clear data. The aim of this study was to investigate sex gender difference in DR type 2 diabetic patients (T2DM). Methods: During 2015-2017 in seven diabetic out- patient clinics in Sardinia we examined under midriatic funduscopy 19.951 (11.409 males, 8.542 females) T2DM with known diabetes duration more than 5 years. Patients were classified as having: a) No DR (NRD),b) Mild non proliferative DR (RDNP), c) pre-proliferative and proliferative DR (RDPP), maculopathy (MAC). Each patient had full clinical and laboratory data available. In the same period in three diabetic outpatient clinics we performed also non midriatic retinography in other 1916 T2DM during the outpatient visit using a semi automated digital fundus camera and each imagine was evaluated by an experienced diabetologist/oculist. Results: Diabetic retinopathy was more frequent under midriatic fundoscopy in males than females: (RDNP 15.9% vs. 14.3%,p&amp;lt;0.01 and RDPP 5,0% vs. 4.0%, p&amp;lt;0.001). Semi automated non midriatic retinography allowed to exclude DR in 68% of patients. Conclusions: Our preliminary results indicate that: a) In this large sample of T2DM with known diabetes duration more than 5 years, DR is present in 24.1% of the subjects, with unit 3 having the highest prevalence (27.6%) and unit 6 the lowest (16.5%), P&amp;lt;0.00001 b) females have significantly less DR than males (p&amp;lt;0.00001), this effect is evident also excluding Unit 3 p=0.0002. c) retinography may allows to exclude DR in almost 68% of outpatient T2DM patients avoiding the more expensive classical oculist assessment. Further analysis is under way in order to identify possible markers of sex gender difference in DR. Disclosure S. Cherchi: None. A. Gigante: None. P. Contini: None. D. Pistis: None. R.M. Pilosu: None. M.A. Spanu: None. M.A. Fois: None. A. Lai: None. G. Meloni: None. G. Tonolo: None.

Feasibility and patient acceptability of a novel artificial intelligence-based screening model for diabetic retinopathy at endocrinology outpatient services: a pilot study

The purpose of this study is to evaluate the feasibility and patient acceptability of a novel artificial intelligence (AI)-based diabetic retinopathy (DR) screening model within endocrinology outpatient settings. Adults with diabetes were recruited from two urban endocrinology outpatient clinics and single-field, non-mydriatic fundus photographs were taken and graded for referable DR ( ≥ pre-proliferative DR). Each participant underwent; (1) automated screening model; where a deep learning algorithm (DLA) provided real-time reporting of results; and (2) manual model where retinal images were transferred to a retinal grading centre and manual grading outcomes were distributed to the patient within 2 weeks of assessment. Participants completed a questionnaire on the day of examination and 1-month following assessment to determine overall satisfaction and the preferred model of care. In total, 96 participants were screened for DR and the mean assessment time for automated screening was 6.9 minutes. Ninety-six percent of participants reported that they were either satisfied or very satisfied with the automated screening model and 78% reported that they preferred the automated model over manual. The sensitivity and specificity of the DLA for correct referral was 92.3% and 93.7%, respectively. AI-based DR screening in endocrinology outpatient settings appears to be feasible and well accepted by patients.

EFFICACY OF NEUROPROTECTIVE SUPPORT OF THE PATIENTS WITH DIABETES MELLITUS DURING PANRETINAL LASER PHOTOCOAGULATION

The purpose of the study was to assess the efficacy of Citicoline influence on morphometric and functional parameters of retina in patients with diabetes mellitus after panretinal laser photocoagulation. We observed 47 patients (79 eyes) with preproliferative diabetic retinopathy which underwent panretinal laser photocoagulation in 3 stages. 28 patients (43 eyes) of main group received Citicoline therapy during 2 months after 1st stage of panretinal laser photocoagulation. The efficacy criteria were the corrected visual acuity changes from baseline, thickness of retinal nerve fiber layer and retinal threshold sensitivity before, after 1, 3, and 6 months after laser photocoagulation. Our results suggest that Citicoline administration after panretinal laser photocoagulation has potential effective influence on retinal nerve fiber layer thickness that allows to recommend it for use as medical support of panretinal laser photocoagulation in patients with diabetes mellitus.

Variability of IOP following laser photocoagulation used in the treatment of diabetic retinopathy

Background: Diabetic retinopathy (DR) is the leading cause of blindness in most industrialized countries. This study was undertaken to assess the variability of IOP following laser photocoagulation used in the treatment of diabetic retinopathy.Methods: This study was conducted at Department of Opthalmology, B.R.D. Medical College, Gorakhpur from June 2015 to December 2016. This study was intended to see the onset and duration of intraocular pressure spikes in diabetic retinopathy patients after green laser photocoagulation (532 nm) (Nidek). Forty patients were followed for next 3 months. The data was analysed by using SPSS version 15.0. Chi-square test and T test was used.Results: Out of 40 patients, 2 (5%) had background Diabetic retinopathy (DR) with maculopathy, 10 (25%) having pre-proliferative DR, 28 (70%) having proliferative DR. Out of 2 BDR patients, 1 (50%) developed immediate post laser angle closure (Schaffer's grade 1) which persisted for 3 days and another had shown no change in angle structure. Out of 10 PPDR patients, no one developed post laser angle closure (0%). Out of 28 PDR patients, 6 (21.4%) had post laser angle closure which included 4 patients who had angle closure before laser, that means around 7% patients developed angle closure in this group. Among these 2 patients, 1 developed angle closure immediately (Schaffer's grade 1) and another developed the same 1 day later and this angle closure (Schaffer's grade 1) remained for 3 days.Conclusions: Laser photocoagulation in diabetic retinopathy patients can cause increase in IOP.

Prevalence and risk factors for diabetic retinopathy in China: a multi-hospital-based cross-sectional study

PurposeTo determine the prevalence and risk factors for diabetic retinopathy (DR) and sight-threatening diabetic retinopathy (STDR) in a multi-hospital-based DR screening programme among patients with diabetes in China, the Lifeline...

Accuracy and reliability of retinal photo grading for diabetic retinopathy: Remote graders from a developing country and standard retinal photo grader in Australia.

BackgroundTo evaluate the accuracy and reliability of fundus retinal photos graded by local graders in Bangladesh with those graded by an expert at the Centre for Eye Research Australia (CERA) in the context of mass scale diabetic retinopathy (DR) screening in Bangladesh.MethodsA population-based cross-sectional study of 3,104 adults identified 213 (7.2%) eligible patients with diabetes of age ≥ 40 years in 2012–2013. Retinal photographs were collected using a non-mydriatic digital fundus retinal camera and a two-field imaging protocol. The photos were graded by two remote graders (G1 and G2) who were trained by a retinal specialist (RS) in Bangladesh, by the RS himself, and by a Centre for Eye Research Australia (CERA) grader. The local graders up skilled their grading ability by comparing 30% of the photos graded by the CERA grader with their own grades. Learning from that exercise was applied to the remaining 70% of photos, which were re-graded. Reliability and accuracy of grading amongst the graders were reported using cross tabulation, inter- and intra-grader reliability, and with sensitivity and specificity.ResultsOf 122 eyes from 61 patients, the mild (R1) DR was estimated to be 14 to 25%, pre-proliferative (R2) DR 4–8%, and proliferative (R3) DR 0.8 to 1.6%, whereas 25%, 8%, 18%, and 15% were found to be ungradable by CERA, RS, G1, and G2, respectively. Of 8 (6.6%) eyes identified as R2 by the CERA grader, 5 (63%), 3 (38%) and 3 (38%) were correctly classified as R2, whereas the rest were classified either as R1 or R3 but none were classified as no DR (R0) or ungradable by the RS, G1 and G2, respectively. After getting experience reviewing the 30% test set graded by the CERA grader, the local graders graded moderate and severe DR with 100% accuracy. After excluding ungradable photos, the sensitivity (specificity) relative to the CERA grader was 82% (88%) before and 80% (93%) after training for G1 and 56% (87%) before and 77% (90%) after training for G2. In case of maculopathy, the CERA grader reported 11.2% eyes with maculopathy, which included 100% of the 4.9% by RS, 6.6% by G1, and 7.4% by G2.ConclusionsLocal graders in Bangladesh are able to grade retinal photos with high accuracy if the DR is at least of a moderate level. With appropriate training and experience, local graders have the ability to contribute significantly to the grading of millions of retinal photos, which required grading in resource- poor countries.

Оценка микрососудистых изменений сетчатки при сахарном диабете методом ОКТ-ангиографии

The Purpose of this work was to determine microvascular changes in the macular zone with diabetes mellitus (DM) and with different stages of diabetic retinopathy (DR) using optical coherence tomography angiography (OCT-A). Materials and methods. 60 patients were inspected (109 eyes) between the ages 58.20 ± 3.27 with DM (patients without clinical DR and with different stages of DR). The control group consisted of 75 healthy subjects (150 eyes) and was compared by gender and age to the DR group. OCT-A was performed with the help of the instrument RTVue XR Avanti (Optovue Inc, USA) in the Angio Retina settings with the scanning field dimensions 3 x 3 mm and 6 x 6 mm. The density of the top vascular plexus in the capillary network was evaluated in 9 quadrants, in the foveal and parafoveal zones, and in the foveal avascular zone (FAZ). Results. In patients with D, all groups were observed to have a significantly decreased density in blood flow in the top capillary network and a widened FAZ in comparison with the control group. The decrease density of blood flow was more evident in groups with preproliferative diabetic retinopathy (prePDR) and with proliferative DR (PDR), averaging at 16.6 % / 13.6 % and 15.5 % / 7.5 % in scanning fields of 3 x 3 mm / 6 x 6 mm, respectively. The FAZ field with DM and DR was at 38.5 %, with nonproliferated DR - at 26.9 %, with prePDR - at 65.4 %, and with PDR at 30.8 % higher than the control group. Conclusion. OCT-A allowed the identity of microvascular changes within the macular zone with DM in even the most early stages of the disease, when there were no manifestations of DR at the eye’s fundus. Early indicators of changes in the microcirculatory path of the retina with DM were qualitative and quantitative changes. These changes were within the FAZ and in the decreased density of the surfacevascular plexus in the capillary network within the scanning fields of 3 x 3 mm Russian ophthalmological journal. 2017; 10 (2): 40-5. (in Russian). doi: 10.21516/2072-0076-2017-10-2-40-45.

Comparison of therapeutic effect of micro-pulse laser and conventional laser on diabetic macular edema

Objective To compare the therapeutic effect of micro-pulse laser, single-spot laser and pattern scan laser for diabetic macular edema(DME). Methods Total of 120 eyes of 60 patients who were confirmed as preproliferative diabetic retinopathy or IV phase proliferative diabetic retinopathy complicated with clinically significant macular edema were included. These patients were randomized divided into the micro-pulse group with 40 eyes of 20 patients, the single-spot laser group with 40 eyes of 20 patients and the pattern scan laser group with 40 eyes of 20 patients.The patients in micro-pulse group underwent micro-pulse laser therapy in macular region , the single-spot laser group underwent macular laser grid photocoagulation therapy by single-spot laser, the pattern scan laser group underwent macular laser grid photocoagulation therapy by pattern scan laser.The BCVA, central macular thickness(CMT) and mean sensitivity(MS) of all patients were examined before and after the treatment. The changes in BCVA, CMT and MS at 6 months after treatment were observed and compared among the groups. Results At 6 months after the treatment, the BCVA of micro-pulse group increased more significantly compared to that before treatment(P 0.05). At 6 months after the treatment, the CMT of micro-pulse group, single-spot laser group and pattern scan laser group decreased significantly compared to those before treatment(P 0.05). At 6 months after the treatment, the MS of micro-pulse group increased significantly compared to that before treatment(P<0.05), the MS of single-spot laser group and pattern scan laser group decreased significantly compared to those before treatment(P<0.05), the MS of the three groups showed statistical difference (P<0.05). Conclusion Micro-pulse laser, single-spot laser and pattern scan laser therapies on DME can effectively reduce CMT and alleviate macular edema, micro-pulse laser therapy on DME also increase BCVA and MS, and improve visual function.Single-spot laser and pattern scan laser therapies can not improve visual function. Key words: Macular edema, diabetic; Micro-pulse laser; Laser coagulation; Effect, therapeutic

Diabetic retinopathy in Tanzania: prevalence and risk factors at entry into a regional screening programme.

ObjectiveThe number of adults with diabetes in sub‐Saharan Africa (SSA) is expected to almost double by 2035. This study investigated the prevalence of diabetic retinopathy (DR) and its risk factors at entry into a community‐based screening programme.MethodsAll persons with diabetes screened for retinopathy at entry into a screening programme in Kilimanjaro Region, Tanzania between November 2010 and December 2014 were included. Fundus photographs were taken with a Topcon retinal camera following pupil dilation. Data were collected on BP, random blood sugar, duration of diabetes, BMI and visual acuity on entry.ResultsA total of 3187 persons were screened for DR. The prevalence of any DR was 27.9% (95%CI 26.4–29.5%) with background diabetic retinopathy (BDR), pre‐proliferative diabetic retinopathy (PPDR) and proliferative diabetic retinopathy (PDR) having a prevalence of 19.1% (95% CI 17.7–20.4%), 6.0% (95%CI 5.2–6.8%) and 2.9% (95%CI 2.3–3.5%), respectively. Maculopathy was present in 16.1% (95%CI 14.8–17.4%) of participants. Multivariable logistic regression analysis for the presence of any DR found independent associations with duration of diabetes (P < 0.0001), systolic BP (P < 0.0001), random blood sugar (P < 0.0001) and attending a government hospital diabetic clinic (P = 0.0339).ConclusionsThis study is the first to present data from a DR screening programme in SSA. The results will provide policymakers with data to aid planning of DR screening and treatment services in the African region. The study highlights the importance of managing comorbidities within DR screening programmes.