Determinants of glaucoma awareness and knowledge in urban Chennai.

Aim: To assess the awareness and knowledge levels about glaucoma and its determinants in an urban population of Chennai in south India.

Materials And Methods: Chennai glaucoma study (CGS) was a population based prevalence study to estimate the prevalence of glaucoma in a rural and urban south Indian population. A total of 3850 subjects aged 40 years or above participated in the urban arm of CGS.

Which is the optimal risk stratification system for surgically treated localized primary GIST? Comparison of three contemporary prognostic criteria in 171 tumors and a proposal for a modified Armed Forces Institute of Pathology risk criteria.

Background: This study aims to validate and compare the performance of the National Institute of Health (NIH) criteria, Huang modified NIH criteria, and Armed Forces Institute of Pathology (AFIP) risk criteria for gastrointestinal stromal tumors (GISTs) in a large series of localized primary GISTs surgically treated at a single institution to determine the ideal risk stratification system for GIST.

Methods: The clinicopathological features of 171 consecutive patients who underwent surgical resection for GISTs were retrospectively reviewed. Statistical analyses were performed to compare the prognostic value of the three risk criteria by analyzing the discriminatory ability linear trend, homogeneity, monotonicity of gradients, and Akaike information criteria.

Association of VEGF gene polymorphisms with diabetic retinopathy in a south Indian cohort.

Background: Polymorphisms in vascular endothelial growth factor (VEGF) gene have been associated with diabetic retinopathy (DR) in various populations. A promoter polymorphism and a 3'UTR variation are studied for association with DR.

Materials And Methods: Type 2 diabetic patients with and without retinopathy were recruited.

Diabetic retinopathy and IGF-1 gene polymorphic cytosine-adenine repeats in a Southern Indian cohort.

Background/aims: Growth factors have been implicated in the pathogenesis of diabetic retinopathy (DR). IGF-1 is known to trigger a critical cascade of molecular events that initiate retinal angiogenesis. Increased vitreous IGF-1 levels have been correlated with the severity of ischemia-associated diabetic retinal neovascularization.

Population norms for frequency doubling perimetry with uncorrected refractive error.

Purpose: To compare the effect of uncorrected refractive error on threshold estimation using frequency doubling perimetry (FDP) full-threshold N-30 with emmetropia among normal subjects.

Methods: One thousand two hundred ninety-nine subjects were enrolled from the Chennai Glaucoma Study, a population-based glaucoma prevalence study. Subjects underwent a comprehensive eye examination including the FDP full-threshold N-30 test.

Intron 4 VNTR of endothelial nitric oxide synthase (eNOS) gene and diabetic retinopathy in type 2 patients in southern India.

A 27-bp variable number tandem repeat (VNTR) in intron 4 of endothelial nitric oxide synthase (eNOS) gene has been associated with the risk for developing diabetic retinopathy (DR) in various ethnic populations. Hundred and eighty seven patients with retinopathy (cases; DR+) and 188 patients without retinopathy (controls: DR-) from southern India who had type 2 diabetes mellitus (T2DM) for more than 10 years, were included in the study. We could neither find significant allelic association with clinical severity of DR nor with macular edema.

Genotype-phenotype correlation analysis in retinoblastoma patients from India.

Background: Genetic analysis has a beneficial impact on retinoblastoma management enabling definite risk assessment. However, information regarding genotype-phenotype correlation in retinoblastoma is limited.

Aim: To analyze the retinoblastoma susceptibility gene for mutations in retinoblastoma patients and correlate the genotypes the phenotypes.

Patient satisfaction levels during teleophthalmology consultation in rural South India.

The application of new technologies for analysis of retinal images, neural networks for automated retinopathy grading, and teleophthalmology have been shown to have great value in ophthalmology. India has only one ophthalmic surgeon for every 107,000 population. Given this situation, teleophthalmology can play a vital role in addressing to the eye care needs of the country.

Diabetic retinopathy in type II diabetics detected by targeted screening versus newly diagnosed in general practice.

Introduction: The aim of this study was to compare the occurrence of diabetic retinopathy in targeted screening diabetic patients (Group I) with newly diagnosed diabetic patients in general practice (Group II).

Materials And Methods: This was an observational cross-sectional study. Data were obtained from 25,313 subjects who participated in the diabetic screening camps, and 128 newly diagnosed diabetes who presented to the diabetic retinopathy screening camps in general practice in rural and urban south India.

Prevalence of angle-closure disease in a rural southern Indian population.

Objective: To estimate the prevalence of primary angle-closure glaucoma, primary angle closure (PAC), and primary angle-closure suspect (PACS) and its associated risk factors in a rural population in southern India.

Methods: Three thousand and nine hundred thirty-four (81.95%) of 4800 enumerated subjects aged 40 years or older underwent a complete ophthalmic examination, including compression gonioscopy.

Karyotyping in retinoblastoma--a statistical approach.

Purpose: Karyotype analysis in hereditary retinoblastoma is considered to be of marginal value in risk prediction due to uncertainties in the assessment of 13q14 deletions. However, it is a low cost genetic test for retinoblastoma in developing countries. In the present study, the results of karyotype analysis were refined by a statistical method to overcome limitations.

Prevalence of open-angle glaucoma in a rural south Indian population.

Purpose: To determine the prevalence of primary open-angle glaucoma (POAG) and the associated risk factors in a rural population in southern India.

Methods: Subjects aged 40 years or more (n = 3934) underwent a complete ophthalmic examination. Glaucoma was diagnosed according to the International Society of Geographical and Epidemiologic Ophthalmology classification.

How high is the non-response rate of patients referred for eye examination from diabetic screening camps?

Aim: To elucidate the rate of non-response among diabetics (recently diagnosed in rural diabetic screening camps) who were referred for eye examination to detect diabetic retinopathy.

Methods: At diabetic retinopathy screening camps, all patients underwent dilated fundus examination using binocular indirect ophthalmoscopy.

Results: Of the 4,111 known diabetics, only 2231(55%) patients attended the diabetic retinopathy screening camps.

Diabetic retinopathy screening model for rural population: awareness and screening methodology.

Context: Worldwide, the prevalence of diabetic retinopathy is increasing at an alarming rate. WHO has predicted that in India the number of adults with diabetes will be the highest in the world: from 19 million in 1995 to 80 million in 2030. Although originally thought to be a disease of an urban population, the prevalence of diabetes mellitus is increasing in rural areas as well.

Sankara Nethralaya-Diabetic Retinopathy Epidemiology and Molecular Genetic Study (SN-DREAMS 1): study design and research methodology.

Purpose: To describe the methodology of the Sankara Nethralaya-Diabetic Retinopathy Epidemiology and Molecular Genetic Study (SN-DREAMS 1), an ongoing population-based study to estimate the prevalence of diabetes and diabetic retinopathy in urban Chennai, Tamil Nadu, South India, and also to elucidate the clinical, anthropometric, biochemical and genetic risk factors associated with diabetic retinopathy.

Methods: In this ongoing study, we anticipate recruiting a total of 5830 participants. Eligible patients, over the age of 40 years, are enumerated using the multistage random sampling method.

Effect of cataract surgery with intraocular lens implant on frequency doubling perimetry.

Purpose: To study the effect of cataract surgery with intraocular lens (IOL) on frequency doubling perimetry (FDP).

Methods: Patients aged 40 years or above seen at our outpatient clinic with no ocular pathology except for visually significant cataract and visual acuity 6/24 or better were eligible. They underwent FDP before and 4 to 6 weeks after cataract surgery with IOL.

Prevalence of refractive errors in a rural South Indian population.

Purpose: To report the prevalence of refractive errors in a rural south Indian population.

Methods: Four thousand eight hundred subjects (age, >39 years) from rural south India were enumerated for a population-based study. All participants underwent complete ophthalmic evaluation.

Methods and design of the Chennai Glaucoma Study.

Purpose: To describe the methodology of a population-based study to estimate the prevalence of glaucoma in a rural and urban South Indian population and to study the genetics of glaucoma in this population.

Methods: A sample size of 4758 each for rural and urban populations in the Indian state of Tamil Nadu was calculated. Eligible subjects aged 40 years and above from the rural study area covering 32 contiguous villages and the urban area comprising five random clusters in Chennai city are enumerated.

Z-2 aldose reductase allele and diabetic retinopathy in India.

Genetic factors have been identified that regulate the severity and the rapidity of onset of retinopathy in diabetic patients. Polymorphisms in (CA)( n) present upstream of the promoter of the aldose reductase (ALR2 ) gene have been shown to be associated with retinopathy in different ethnic populations. We aimed to study the association between the (CA)( n) polymorphism and type 2 diabetic patients with and without retinopathy in the Asian Indian population.

Association of Gly82Ser polymorphism in the RAGE gene with diabetic retinopathy in type II diabetic Asian Indian patients.

Aim/hypothesis: The binding of advanced glycation end products (AGE) to the receptor induces cellular oxidative stress and vascular dysfunction and this is implicated in the pathogenesis of diabetic retinopathy (DR). This study aims to investigate the frequency of Gly82Ser polymorphism in exon 3 of the receptor for AGE (RAGE) gene and its association with DR in Asian Indian patients who have type II diabetes.

Methods: 200 Asian Indian patients with at least 15-year duration of type II diabetes were identified.