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Here, we communicate the draft genome sequence of an ocular Mycobacterium tuberculosis strain (SNMICRO 2047-20) that was isolated from the vitreous fluid of a patient diagnosed with endophthalmitis. The genome sequence was 4,391,538 bp long with 3,898 protein-encoding genes and clustered to the East African-Indian lineage.

Purpose To compare metastasis-related mortality, local treatment failure, and globe salvage after retinoblastoma in countries with different national income levels. Design International, multicenter, registry-based retrospective case series. Participants Two thousand one hundred ninety patients, 18 ophthalmic oncology centers, and 13 countries on 6 continents. Methods Multicenter registry-based data were pooled from retinoblastoma patients enrolled between January 2001 and December 2013. Adequate data to allow American Joint Committee on Cancer staging, eighth edition, and analysis for the main outcome measures were available for 2085 patients. Each country was classified by national income level, as defined by the 2017 United Nations World Population Prospects, and included high-income countries (HICs), upper middle-income countries (UMICs), and lower middle-income countries (LMICs). Patient survival was estimated with the Kaplan-Meier method. Logistic and Cox proportional hazards regression models were used to determine associations between national income and treatment outcomes. Main Outcome Measures Metastasis-related mortality and local treatment failure (defined as use of secondary enucleation or external beam radiation therapy). Results Most (60%) study patients resided in UMICs and LMICs. The global median age at diagnosis was 17.0 months and higher in UMICs (20.0 months) and LMICs (20.0 months) than HICs (14.0 months; P Conclusions This international, multicenter, registry-based analysis of retinoblastoma management revealed that lower national income levels were associated with significantly higher rates of metastasis-related mortality, local treatment failure, and lower globe salvage.

Purpose To evaluate the ability of the American Joint Committee on Cancer (AJCC) 8th edition to predict local tumor control and globe salvage for children with retinoblastoma (RB). Design International, multicenter, registry-based retrospective case series. Participants A total of 2854 eyes of 2097 patients from 18 ophthalmic oncology centers from 13 countries over 6 continents. Methods International, multicenter, registry-based data were pooled from patients enrolled between January 2001 and December 2013. All RB eyes with adequate records to allow tumor staging by the AJCC 8th edition criteria and follow-up to ascertain treatment outcomes were included. Main Outcome Measures Globe-salvage rates were estimated by AJCC clinical (cTNMH) categories and tumor laterality. Local treatment failure was defined as use of enucleation or external beam radiation therapy (EBRT), with or without plaque brachytherapy or intra-arterial chemotherapy (IAC). Results Unilateral RB occurred in 1340 eyes (47%). Among the 2854 eyes, tumor categories were cT1 to cT4 in 696 eyes (24%), 1334 eyes (47%), 802 eyes (28%), and 22 eyes (1%), respectively. Of these, 1275 eyes (45%) were salvaged, and 1179 eyes (41%) and 400 eyes (14%) underwent primary and secondary enucleation, respectively. The 2- and 5-year Kaplan–Meier cumulative globe-salvage rates without the use of EBRT by cTNMH categories were 97% and 96% for category cT1a tumors, 94% and 88% for cT1b tumors, 68% and 60% for cT2a tumors, 66% and 57% for cT2b tumors, and 32% and 25% for cT3 tumors, respectively. Risk of local treatment failure increased with increasing cT category (P Conclusions Multicenter, international, internet-based data sharing validated the 8th edition AJCC RB staging to predict globe-salvage in a large, heterogeneous, real-world patient population with RB.

Purpose To evaluate the ability of the 8th edition of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual to estimate metastatic and mortality rates for children with retinoblastoma (RB). Design International, multicenter, registry-based retrospective case series. Participants A total of 2190 patients from 18 ophthalmic oncology centers from 13 countries over 6 continents. Methods Patient-specific data fields for RB were designed and selected by subcommittee. All patients with RB with adequate records to allow tumor staging by the AJCC criteria and follow-up for metastatic disease were studied. Main Outcome Measures Metastasis-related 5- and 10-year survival data after initial tumor staging were estimated with the Kaplan–Meier method depending on AJCC clinical (cTNM) and pathological (pTNM) tumor, node, metastasis category and age, tumor laterality, and presence of heritable trait. Results Of 2190 patients, the records of 2085 patients (95.2%) with 2905 eyes were complete. The median age at diagnosis was 17.0 months. A total of 1260 patients (65.4%) had unilateral RB. Among the 2085 patients, tumor categories were cT1a in 55 (2.6%), cT1b in 168 (8.1%), cT2a in 197 (9.4%), cT2b in 812 (38.9%), cT3 in 835 (40.0%), and cT4 in 18 (0.9%). Of these, 1397 eyes in 1353 patients (48.1%) were treated with enucleation. A total of 109 patients (5.2%) developed metastases and died. The median time (n = 92) from diagnosis to metastasis was 9.50 months. The 5-year Kaplan–Meier cumulative survival estimates by clinical tumor categories were 100% for category cT1a, 98% (95% confidence interval [CI], 97–99) for cT1b and cT2a, 96% (95% CI, 95–97) for cT2b, 89% (95% CI, 88–90) for cT3 tumors, and 45% (95% CI, 31–59) for cT4 tumors. Risk of metastasis increased with increasing cT (and pT) category (P Conclusions Multicenter, international, internet-based data sharing facilitated analysis of the 8th edition AJCC RB Staging System for metastasis-related mortality and offered a proof of concept yielding quantitative, predictive estimates per category in a large, real-life, heterogeneous patient population with RB.

Purpose: Vitreoretinal lymphoma (VRL) is the most common intraocular lymphoma (IOL). This can be either primary or secondary to the central nervous system lymphoma. The diagnosis of primary intraocular lymphoma (PIOL) currently relies on clinical diagnosis and cytological analysis of the vitreous or subretinal biopsy. Although most cases are diagnosed without much issue, the limited amount of vitreous fluid, subjectivity in cytological reporting, and special expertise in ocular pathology make the diagnosis challenging. MYD88 L265P mutation has been implicated to have diagnostic utility in PIOL. In this study, we screened consecutive vitreous biopsies for the presence of MYD88 L265P mutation to understand its diagnostic utility compared to conventional cytological analysis. Methods: Cytological analysis and MYD88 L265P mutation by PCR-based sequencing and restriction fragment length polymorphism (RFLP) were carried out on consecutive vitreous and subretinal biopsies collected from 21 patients. The diagnostic utility of the cytology and MYD88 L265P mutation analysis were compared. Results: Out of the 21 patients, 15 had clinical suspicion of having PIOL. Out of these suspected cases of PIOL, nine were confirmed on follow-up, while six were diagnosed as other intraocular pathologies. Diagnostic utility of MYD88 L265P mutation analysis revealed a sensitivity of 88.9%, specificity of 91.6%, positive and negative predictive value of 88.9% and 91.7%, respectively. Diagnostic accuracy of 90.5% was achieved with the mutation analysis that shows the superiority of MYD88 in both ruling in and ruling out PIOL. The diagnostic utility of MYD88 L265P mutation was superior to conventional cytological analysis. Conclusion: The analysis of MYD88 L265P mutation is reliable and efficient in the diagnosis of PIOL.

Purpose: To report the prevalence and risk factors of cataract and its subtypes in older age group. Methods: A total of 6617 subjects were recruited from both rural and urban areas. A detailed history including data on demographic, socioeconomic and ocular history was obtained. Lens opacity was graded according to the Lens Opacity Classification System III (LOCS III). Results: Cataract was present in 1094 of the rural and 649 subjects in the urban population. Monotype subtype cataracts were found in 32% and 25% in rural and urban population and 12.68% and 18.6% were mixed cataracts in the rural and urban groups. In baseline characteristics history of diabetes, alcohol intake and presence of age-related macular degeneration were the risk factors in urban group. On multivariate analysis, the only significant risk factors for any cataract in subjects ≥60 years were increasing age in both rural [odds ratio (OR), 1.07] and urban (OR, 1.08) population, and HbA1c (OR, 1.14) in rural population. Overweight (OR, 0.6) was found to be a protective factor, and lower social economic status (OR, 1.52) a risk factor for cataract in urban population. A significant urban–rural difference was found in the prevalence of cataract and its subtypes (P ≤ 0.05). Conclusion: We found the risk factors for any cataract in older age group to be increasing age and HbA1c in rural group. Age and lower social economic status were found to be the risk factors in urban arm. A statistically significant difference was found on comparison of the prevalence of cataract and its subtypes between the rural and urban population.

Purpose: To report two rare cases of chronic myeloid leukemia (CML) on tyrosine kinase inhibitors presenting as bilateral serous retinal detachment and ocular inflammation, simulating Vogt-Koyanagi-Harada (VKH) disease. Methods: Case series and review of literature. Result: Two young patients (one male and one female) with CML on treatment with tyrosine kinase inhibitors (imatinib and dasatanib) under remission presented with bilateral sudden vision loss. One patient had bilateral multiple pockets of serous retinal fluid while the other had panuveitis with exudative retinal detachment. There was neither prodromal symptoms nor systemic signs and symptoms suggestive of VKH in both cases. They responded well to systemic steroid therapy without recurrences with complete visual recovery. Conclusion and importance: CML patients can have features similar to VKH even during stable hematological phase and may be possibly associated with the use of tyrosine kinase inhibitors. Hence it is important not to misdiagnose and treat such patients with long term immunomodulators. Keywords: Chronic myeloid leukemia, Panuveitis, Vogt-Koyanagi-Harada disease, Tyrosine kinase inhibitors, Dasatinib, Imatinib

Purpose To explore any relationship between the markers of early retinal neuronal damage and peripheral diabetic neuropathy in subjects with no diabetic retinopathy (DR). Methods A cross-sectional study in which type 2 diabetic subjects (n=743) without DR were studied. Visual functions including visual acuity, contrast sensitivity, colour vision, retinal sensitivity using microperimeter and retinal thicknesses by spectral domain optical coherence tomography were measured. Vibration perception thresholds of greater than or equal to 20 µV, measured by sensitometer using a biothesiometer probe, were defined as having peripheral diabetic neuropathy. Statistical analyses were performed using independent t-test, multivariate logistic regression and Pearson9s correlation. Results Of 743 subjects who had no DR, 24.9% had diabetic neuropathy. Independent comparisons among subjects who had diabetic neuropathy compared with those who did not showed statistically significant retinal nerve fibre layer thinning (p=0.01), reduced contrast sensitivity (p=0.0001), reduced retinal sensitivity (p=0.03), impaired colour vision (p=0.04) and reduced visual acuity (p=0.0001). Multivariate analysis showed significant association between the mean retinal sensitivity (measured using a microperimeter) and diabetic neuropathy (adjusted OR (95% CI): 0.76 (0.60 to 0.95), p=0.01). Conclusions Significant association of neuroretinal dysfunction with the presence of diabetic neuropathy was noted among subjects with no DR.

Although there have been many population-based studies of age-related macular degeneration (AMD), only limited information is available in Asia on the epidemiology of geographic atrophy (GA). We aimed to determine the prevalence and patterns of GA through an analysis of multiple studies conducted within the Asian Eye Epidemiology Consortium (AEEC).Cross-sectional meta-analyses.A total of 97 213 individuals aged 40 years and older.Data from 22 population-based studies from countries belonging to the AEEC were included. In all studies, AMD was defined on the basis of standardized grading systems. Geographic atrophy was defined as an area of pallor in the fundus with visibility of the underlying choroidal blood vessels and sharply defined borders. Random-effects meta-analysis was performed to estimate overall and age-, gender-, and region-specific pooled prevalence of GA.Prevalence of GA per 1000 persons.The mean age was 60.8 ± 10.0 years, and 42 673 (43.9%) were male. Overall, a total of 223 individuals (0.2%) had GA. The pooled overall prevalence of GA was 1.57 per 1000 persons (95% confidence interval [CI], 1.04-2.10), which was 3 times less than that of neovascular AMD of 5.20 per 1000 persons (95% CI, 3.97-6.43). Compared with those aged 50 to 59 years, the prevalence of GA increased from 0.34 per 1000 persons (95% CI, 0.07-0.62) to 2.90 per 1000 persons (95% CI, 1.55-4.25) in those aged ≥70 years. The GA prevalence per 1000 persons was similar between urban (2.22; 95% CI, 1.22-3.23) and rural residents (1.33; 95% CI, 0.70-1.96). Geographic atrophy was more prevalent in South Asia (based on studies from India and Nepal, 3.82 per 1000 persons; 95% CI, 1.72-5.93) compared with East Asia (based on studies from China, Korea, Hong Kong, Taiwan, and Japan, and the Singapore Chinese Eye Study, 0.76 per 1000 persons; 95% CI, 0.31-1.22, P = 0.005).Geographic atrophy is uncommon in Asian populations compared with those of European ancestry. Even within Asia, geographic differences in GA prevalence were seen. The findings of this meta-analysis suggest that better dissection of risk factors in the Asian population for GA may provide insights into the biological pathways that drive these late-stage manifestations, thus suggesting better targets for prevention.

A 44-year-old male patient presented with features suggestive of transient central retinal artery occlusion (CRAO) followed by permanent CRAO and lateral posterior ciliary artery occlusion. He had diagnostic features of polycythemia vera (PV). When presented for the first time, the patient had features of ocular ischemia such as ocular pain, conjunctival congestion, and retinal opacification but with normal arm-to-retina time and normal arteriovenous transit time. During the second presentation, he had ocular pain, congested conjunctiva, retinal opacification, cherry red spot with box-carrying of retinal vessels, and choroidal infarct (Amalric's sign). He had lost light perception in that eye. Patients with polycythemia are prone to multifocal vascular occlusions and this can be the presenting feature in PV. A timely diagnosis and prompt management can prevent these repeated thromboembolic occlusive episodes.

Retinoblastoma (RB) is a childhood eye cancer. Currently, chemotherapy, local therapy, and enucleation are the main ways in which these tumors are managed. The present work is the first study that uses constraint-based reconstruction and analysis approaches to identify and explain RB-specific survival strategies, which are RB tumor specific. Importantly, our model-specific secretion profile is also found in RB1-depleted human retinal cells in vitro and suggests that novel biomarkers involved in lipid metabolism may be important. Finally, RB-specific synthetic lethals have been predicted as lipid and nucleoside transport proteins that can aid in novel drug target development.

Aim: The aim was to assess the foveal slope configuration in subjects with type 2 diabetes in a population-based study. Materials and Methods: A subset of 668 subjects from Sankara Nethralaya Diabetic Retinopathy (DR) Epidemiology and Molecular Genetics Study II, a population-based study, were included in the current study. All the subjects underwent comprehensive ophthalmic evaluation including spectral domain optical coherence tomography. Foveal thickness was assessed in five central early treatment DR study quadrants from the three-dimensional scan and foveal slope was calculated in all the four quadrants. Results: Subjects with sight-threatening DR (STDR) had significantly shallow foveal slope in inferior quadrant (STDR: 7.33 ± 6.26 vs. controls: 10.31 ± 3.44; P = 0.021) when compared to controls and in superior (STDR: 7.62 ± 5.81 vs. no DR: 9.11 ± 2.82; P = 0.033), inferior (STDR: 7.33 ± 6.26 vs. no DR: 8.81 ± 2.81; P = 0.048), and temporal quadrants (STDR: 6.69 ± 5.70 vs. no DR: 7.97 ± 2.33; P = 0.030) when compared to subjects with no DR. Foveal slope was significantly shallow among the older age groups in subjects with no DR (P < 0.001) and non-STDR (P = 0.027). Average foveal slope in the diabetic subjects was independently and significantly correlated with increase in age (r = −0.241; P < 0.001) and central subfield thickness (r = −0.542; P < 0.001). Conclusion: Changes in foveal slope were seen with increasing age; however, in diabetes these segmental slope changes can be seen in late DR (STDR).

Purpose: The purpose of this study is to assess color vision abnormalities in a cohort of subjects with type II diabetes and elucidate associated risk factors. Methods: Subjects were recruited from follow-up cohort of Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study I. Six hundred and seventy-three eyes of 343 subjects were included from this population-based study. All subjects underwent detailed ophthalmic evaluation, including the Farnsworth-Munsell 100 hue test. Results: The prevalence of impaired color vision (ICV) was 43% (CI: 39.2–46.7). Risk factors for ICV were higher heart rate (odds ratio [OR]: 1.043, [1.023–1.064]) and a higher intraocular pressure (IOP) (OR: 1.086, [1.012–1.165]). Subjects with clinically significant macular edema (CSME) had three times higher chance of having ICV. C1, C2, and C3 are the commonly found Early Treatment Diabetic Retinopathy Study (ETDRS) patterns. The moment of inertia method showed that the angle did not reveal any specific pattern of color vision defect. Although the major and minor radii were high in those with ICV, we did not observe polarity. Confusion index was high in subjects with ICV, indicating a severe color vision defect. Conclusions: The prevalence of ICV was 43% among subjects with type II diabetes. The most commonly observed patterns were increasing severities of the blue–yellow defect on ETDRS patterns, but no specific pattern was observed at the moment of inertia analysis. The presence of CSME, a higher heart rate, and IOP was significant risk factors for ICV. This functional impairment in color vision could significantly contribute to morbidity among subjects with diabetes.

Purpose To assess impairment of colour vision in type 2 diabetics with no diabetic retinopathy and elucidate associated risk factors in a population-based cross-sectional study. Methods This is part of Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular-genetics Study (SN-DREAMS II) which was conducted between 2007–2010. FM 100 hue-test was performed in 253 subjects with no clinical evidence of diabetic retinopathy. All subjects underwent detailed ophthalmic evaluation including cataract grading using LOCS III and 45° 4-field stereoscopic fundus photography. Various ocular and systemic risk factors for impairment of colour vision (ICV) were assessed in subjects with diabetes but no retinopathy. P value of < 0.05 was considered statistically significant. Results The mean age of the study sample was 57.08 ± 9.21 (range: 44–86 years). Gender adjusted prevalence of ICV among subjects with diabetes with no retinopathy was 39.5% (CI: 33.5–45.5). The mean total error score in the study sample was 197.77 ± 100 (range: 19–583). The risk factors for ICV in the study were women OR: 1.79 (1.00–3.18), increased resting heart rate OR: 1.04 (1.01–1.07) and increased intraocular pressure OR: 1.12 (1.00–1.24). Significant protective factor was serum high-density lipoprotein OR: 0.96 (0.93–0.99). Conclusions Acquired ICV is an early indicator of neurodegenerative changes in the retina. ICV found in diabetic subjects without retinopathy may be of non-vascular etiology.

Purpose We report the 4-year incidence, progression, and risk factors of cataract subtypes in type 2 diabetes. Methods A total of 779 subjects completed baseline and 4-year follow-up. Results The incidences of nuclear opalescence (NO), nuclear color (NC), cortical cataract (CC), and posterior subcapsular cataract (PSC) were 70%, 55.2%, 25.7%, and 7.3%, respectively. One-step progressions of NO, NC, CC, and PSC were 14.3%, 16.1%, 8.8%, and 8.1%, respectively, and two-step or more progressions were 5.0%, 6.0%, 0.8%, and 6.0%, respectively. Incident NO was seen in patients 50 to 59 (odds ratio [OR] = 3.3), NC in those 50 to 59 (OR = 2.7) and 60 to 69 (OR = 3.9), and CC in those 60 to 69 (OR = 3.3) years old. A lower hemoglobin A1c (HbA1c; OR = 0.7), longer diabetes duration (OR = 1.1), and hyperopia (OR = 4.0) were associated with incident PSC. Women (OR = 1.7) and patients with higher total cholesterol (OR = 1.3) at baseline showed one-step NO progression. Patients 60 to 69 (OR = 2.8) and ≥70 (OR = 3.8) years old showed one-step NC progression, while those 60 to 69 years old showed one-step CC progression (OR = 6.3). A lower HbA1c (OR = 0.3) was associated with one-step PSC progression. A higher low-density lipoprotein (OR = 1.6) was associated with two-step or more NO progression. Patients 60 to 69 years old (OR = 6.7) had a greater risk, while those with hyperopia at baseline (OR = 0.2) had lower risk of two-step or more NC progression. Patients 40 to 49 years old constituted the reference group for all. Conclusions The 4-year cumulative incidence of cataract is higher than that of progression. Greater age is a risk factor for incidence and progression of most types of cataract.

Purpose: The aim of this study is to investigate the 4-year incidence and progression of visual impairment (VI) and the associated risk factors for incident VI in a South Indian population with type 2 diabetes. Methods: A total of 634 participants with type 2 diabetes were found eligible after 4 years. Visual acuity (VA) was estimated using the modified Early Treatment Diabetic Retinopathy Study protocol. VA in the better eye was considered for the assessment of VI based on the World Health Organization criteria. Mild VI was defined as VA 4.0 (odds ratio [OR]: 2.612 [1.148–5.942], P = 0.022) and lower socioeconomic score (OR: 0.965 [95% confidence interval, (0.933-0.998)], P = 0.040) were associated with the risk of future incident VI. Refractive error (47%) and cataract (30%) were identified as the leading causes of incident VI at follow-up. Conclusions: VI seems to be a significant problem among diabetic participants in the South Indian population. Refractive error and cataract are the leading but treatable causes of incident VI in this population and would benefit from intervention.

Objective The study was aimed at estimating the prevalence of type 2 diabetes mellitus and diabetic retinopathy in a rural population of South India. Design A population-based cross-sectional study. Participants 13 079 participants were enumerated. Methods A multistage cluster sampling method was used. All eligible participants underwent comprehensive eye examination. The fundi of all patients were photographed using 45°, four-field stereoscopic digital photography, and an additional 30° seven-field stereo digital pairs were taken for participants with diabetic retinopathy. The diagnosis of diabetic retinopathy was based on Klein9s classification. Main outcome measures Prevalence of diabetes mellitus and diabetic retinopathy and associated risk factors. Results The prevalence of diabetes in the rural Indian population was 10.4% (95% CI 10.39% to 10.42%); the prevalence of diabetic retinopathy, among patients with diabetes mellitus, was 10.3% (95% CI 8.53% to 11.97%). Statistically significant variables, on multivariate analysis, associated with increased risk of diabetic retinopathy were: gender (men at greater risk; OR 1.52; 95% CI 1.01 to 2.29), use of insulin (OR 3.59; 95% CI 1.41 to 9.14), longer duration of diabetes (15 years; OR 6.01; 95% CI 2.63 to 13.75), systolic hypertension (OR 2.14; 95% CI 1.20 to 3.82), and participants with poor glycemic control (OR 3.37; 95% CI 2.13 to 5.34). Conclusions Nearly 1 of 10 individuals in rural South India, above the age of 40 years, showed evidence of type 2 diabetes mellitus. Likewise, among participants with diabetes, the prevalence of diabetic retinopathy was around 10%; the strongest predictor being the duration of diabetes.

Objective: To report the prevalence of myopia and its association with diabetic retinopathy in subjects with type II diabetes mellitus and compare the diabetic retinopathy status in the myopic group vs the emmetropic group. Design: Population-based study. Materials and Methods: The population-based study estimated the prevalence of myopia from 1058 subjects, who were more than 40 years old and had type II diabetes mellitus; the patients were enrolled from a cross-sectional study. Participants answered a detailed questionnaire and underwent biochemical, physical and comprehensive ocular examination which included grading of nuclear sclerosis by lens opacities classification system III (LOCS III), seven field fundus photography and ultrasonography. Diabetic retinopathy and diabetic maculopathy were graded using the Klein's classification and early treatment diabetic retinopathy study (ETDRS) criteria respectively. Results: The prevalence of mild, moderate and high myopia in type 2 diabetes was 15.9, 2.1 and 1.9% respectively. The prevalence of any myopia was found to be 19.9% in our study population. After adjusting the age, gender, duration of diabetes, hemoglobin A1c and other factors, increasing age was associated with mild and moderate myopia [OR 1.11 (95% CI 1.05 - 1.18)]. Compared to emmetropia, complete posterior vitreous detachment (CPVD) was associated with high myopia (50% Vs 12.2%, P < 0.0001). Myopia had no association with diabetic retinopathy. Conclusion: The prevalence of myopia and high myopia was found to be 19.9 and 1.9% respectively among subjects with type II diabetes. Myopia was not associated with diabetic retinopathy, thereby, suggesting the need for a longitudinal study.

Background To describe the methodology of the Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetic Study III, an ongoing epidemiological study to estimate the prevalence of Diabetes and Diabetic Retinopathy in rural population of Kanchipuram and Thiravallur districts of Tamil Nadu, India and to elucidate the clinical, anthropometric, biochemical and genetic risk factors associated with diabetic retinopathy in this rural population. Methods Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetic Study III will be a mobile van based epidemiological study; 11,760 participants aged ≥ 40 years will be recruited from the study areas. Eligible subjects will undergo blood sugar estimation to diagnose Diabetes. Oral Glucose Tolerance Test will be done to conform diabetes. All subjects with diabetes will undergo complete information of knowledge, aptitude and practice of diabetes and diabetic retinopathy, Diet questionnaire, demographic data, socioeconomic status, physical activity, anthropometric measurements, and risk of sleep apnoea. A detailed medical and ocular history, a comprehensive eye examination including refraction, slit lamp biomicroscopy examination, indirect ophthalmoscopy, slit lamp biomicroscopy, digital stereo fundus photography and ultrasound of eye will be done in the mobile van. Blood will be collected for biochemical investigations including blood hemoglobin, glycosylated hemoglobin, lipid profile, urea and creatinine, genetic study. Urine will be collected for microalbuminuria. All fundus photographs will be graded at base hospital. Participants who need treatment will be sent to the base hospital. A computerized database is created for the records. Conclusion The study is expected to provide an estimate of the prevalence of Diabetes and Diabetic Retinopathy and also a better understanding of the genetic, anthropometric and socio-economic risk factors associated with Diabetic Retinopathy in a Rural South Indian population.

Background The Metabolic syndrome (MS) consists of central obesity, glucose intolerance, hyperinsulinemia, low high density lipoproteins, high triglycerides and hypertension. Different studies have observed that MS causes microvascular complications in patients with type 2 diabetes. The aim of the study was to find out the prevalence of MS in the Indian population with type 2 diabetes mellitus in relation to gender, duration of diabetes, and to evaluate the influence of MS and its individual components on microvascular complications such as diabetic retinopathy, diabetic nephropathy and diabetic neuropathy. Methods A population-based cross sectional survey was conducted with 1414 patients having type 2 diabetes mellitus. The International Diabetes Federation (IDF) criteria were used to identify the metabolic syndrome. Diabetic retinopathy was graded using the stereoscopic digital fundus photography. Neuropathy was assessed by measuring the vibration perception threshold through a sensitometer. Nephropathy was diagnosed by the presence of microalbuminuria in the first morning urine sample. Results The age and gender adjusted prevalence of MS, using the IDF criteria, in the South Indian population was 73.3%. The prevalence was higher in women (83.3%), compared to men (65.3%). In subjects with diabetes mellitus, without and with MS, the prevalence of retinopathy was 21.3% and 16.9% (p = 0.057); prevalence of nephropathy was 20.5% and 18.0% (p = 0.296), and prevalence of neuropathy was17.2% and 19.4% (p = 0.353) respectively. Overall and in women, the clustering of MS components led to an increase in the prevalence of diabetic nephropathy. The prevalence of retinopathy and neuropathy in MS subjects, who had diabetes for < 10 years, was more in both men and women; it was more in women but not in men when the duration of diabetes varied from 11-20 years. Conclusions The association of MS with microangiopathies decreased with an increase in the duration of diabetes. MS behaved differently in men and women. It may need to be managed differently in the two groups.