Prevalence and associated factors of diabetic retinopathy among people with diabetes screened using fundus photography at a community diabetic retinopathy screening program in Nepal.

BACKGROUND: This study aimed to assess the prevalence and associated factors of diabetic retinopathy (DR) and vision threatening DR (VTDR) among people with diabetes screened using fundus photography in Nepal. METHODS: This is a retrospective study among people with diabetes presented for DR screening using fundus photography from 2013 to 2019. Detailed demographics, duration of diabetes, medical history, visual acuity, and grading of DR on fundus photography were analyzed. Fundus camera used in the study were;Topcon digital fundus camera 900 CXR and digital portable fundus cameras (Nidek-10 portable non-mydriatric fundus camera; Versacam & Trade & Alpha, France), and a Zeiss portable fundus camera (Zeiss Visucout 100). Macula centred and disc centred 45 degree two images were taken from each eye. Pupil were dilated in cases where there was media haze in un-dilated cases. DR was graded using early treatment diabetic retinopathy study criteria. The images were graded by fellowship trained retina specialist. DR prevalence included any DR changes in one or both eyes. RESULTS: Total of 25,196 patients with diabetes were enrolled. Mean age was 54.2 years with Standard Deviation (S.D):12.9 years, ranging from 6 years to 97 years. Type 1 and type 2 diabetes comprised of 451 people (1.79%) and 24,747 (98.21%) respectively. Overall, 1.8% of the images were un-gradable. DR prevalence was 19.3% (95% Confidence Interval (CI): 18.8 - 19.7%). DR prevalence in type 1 and type 2 diabetes was 15.5% (95% CI: 12.5 - 18.6%) and 19.3% (CI: 18.8 - 19.8%) respectively. Clinically significant macular edema (CSME) was found in 5.9% (95% CI: 5.6-6.2%) and VTDR in 7.9% (95% CI: 7.7-8.3%). In multivariate analysis, our study revealed strong evidence to suggest that there is meaningful association between DR and VTDR with duration of diabetes, diabetic foot, diabetic neuropathy, agriculture occupation, those under oral hypoglycaemic agents or insulin or both as compared to those under diet only, and presenting visual acuity > 0.3LogMAR. CONCLUSION: Prevalence and associated factors for DR and VTDR were similar to other DR screening programs in the region. Emphasis on wider coverage of DR screening could help for timely detection and treatment of STDR to avoid irreversible blindness.

Treatment outcomes of retinal vein occlusion in clinical practice in Nepal.

BACKGROUND: This study evaluated the treatment outcomes of retinal vein occlusion (RVO) in a routine clinical practice in Nepal. METHODS: This was a retrospective analysis of observational data of patients with RVO who attended the retina clinic of the Tilganga Institute of Ophthalmology from 1 November 2017 to 31 October 2018. The main outcome was the mean change in visual acuity (VA) at 12 months from the start of treatment. Other outcomes of interest were the mean change in central subfield thickness (CST) and the number of treatments over 12 months. RESULTS: A total of 99 eyes (of 99 patients) with RVO (60 - branch RVO [BRVO] and 39 - central RVO [CRVO] were available for the analysis. Eyes with CRVO had worse VA and CST at baseline. Eyes in both groups were similar for age, associated factors for RVO, duration of vision loss and the presence of ischemia at baseline. The mean (95% Confidence Interval [CI]) VA change at 12 months for BRVO was - 0.35 (- 0.46, - 0.23) logMAR (p < 0.001) from a mean (SD) of 0.75 (0.42) logMAR at baseline with 63% achieving VA < 0.3 logMAR while for CRVO it was - 0.35 (- 0.46, - 0.23) logMAR (p = 0.19) from 1.13 (0.61) logMAR at baseline and VA < 0.3 logMAR in 36%. The mean (95% CI) change in CST over 12 months was - 114 (- 189, - 40) µm (p = 0.003) from a mean (SD) of 423 (151) µm at baseline for BRVO and - 184(- 276, - 91) µm (p < 0.001) from 519 (213) µm for CRVO. Patients in both groups received a median of 2 bevacizumab injections over 12 months. Around 37% eyes were lost before 12 months' observation. The mean VA and CST trajectory in these eyes at their last visit was similar to those that completed 12 months. CONCLUSION: The outcomes of RVO over the 12 months were inferior and the number of treatments fewer than those of the clinical trials and other reports from routine clinical practice. Future studies to identify the treatment barriers are warranted to improve the treatment outcomes in our patients.

Prevalence and causes of low vision and blindness in an elderly population in Nepal: the Bhaktapur retina study.

BACKGROUND: This study aims to explore the prevalence and causes of low vision and blindness focused on retinal disease in a population above 60 years in Nepal. METHODS: Two thousand one hundred subjects were enrolled in a population-based cross-sectional study. History, presenting and best corrected visual acuity after subjective refraction, anterior and posterior segment examinations was obtained in detail. RESULTS: Among the total subjects, 1860 (88.57%) had complete information. Age varies from 60 to 95 (mean age: 69.64 ± 7.31) years. Low vision and blindness in both eyes at presentation was found in 984 (52.90%, 95% confidence interval (CI): 50.60-55.19) and 36 (1.94%, 95% CI: 1.35-2.66) subjects respectively. After best correction, bilateral low vision and blindness was found in 426 (22.92%, 95% CI: 21.01-24.88), and 30 (1.61%, 95% CI: 0.10-2.30) subjects respectively. As compared to 60-69 years old, risk of visual impairment was four times higher (95% CI:3.26-5.58) in the 70-79 year olds and 14 times higher (95% CI: 9.72-19.73) in the age group 80 years and above. Major causes of bilateral low vision were cataract (68.07%), followed by retinal disorders (28.64%), and for blindness; retinal disorders (46.66%), followed by cataract (43.33%). Illiteracy was significantly associated with visual impairment. CONCLUSION: Among the elderly population, prevalence of visual impairment was high. Refractive error, cataract and retinal disorders were the major cause of low vision. Screening the population at the age 60 years and above, focused on cataract and posterior segment diseases, providing glasses and timely referral can help reduce visual impairment.

Prevalence, pattern and risk factors of retinal vein occlusion in an elderly population in Nepal: the Bhaktapur retina study.

BACKGROUND: This study aims to explore the prevalence, pattern and risk factors of retinal vein occlusion (RVO) in an elderly population of Nepal. METHOD: One thousand eight hundred sixty subjects of age 60 years and above were enrolled in a population-based, cross-sectional study. Detailed history, visual acuity, anterior segment and posterior segment examinations were done. Blood pressure, non-fasting blood sugar, body mass index and abdominal girth were measured. Retinal vein occlusions were further divided into branch retinal (BRVO), hemi-retinal and central retinal vein occlusion (CRVO). RESULT: Age ranged from 60 to 95 years with a mean of 69.64 ± 7.31 years. Overall population prevalence for RVO was 2.95% (95% Confidence interval (CI): 2.23-3.83), BRVO 2.74% (95% CI: 2.05-3.58) and CRVO 0.21% (95% CI: 0.06-0.55). BRVO was seen in 51 subjects (92.73%) and CRVO in 4 (7.27%). Among the total RVO, unilateral and bilateral involvement was 85.45% and 14.55%, respectively. Among the subjects with BRVO and CRVO, 37.25% and 50% had low vision, respectively. The risk of RVO increased with ageing and was more among males. There was an increased risk of RVO among those with hypertension, and with diabetes and hypertension. There was also an increased risk of RVO among subjects with hypermetropia, those with pseudophakia and those who were smokers and consumed alcohol. CONCLUSION: Retinal vein occlusion is a common retinal vascular disorder in the elderly population of Nepal. The main risk factors for RVO were increasing age and hypertension.

Nd:YAG laser hyaloidotomy in the management of Premacular Subhyaloid Hemorrhage.

BACKGROUND: Premacular subhyaloid hemorrhage results in a sudden profound loss of vision. Among the modalities for its treatment, Nd:YAG laser hyaloidotomy is a non invasive method enabling rapid drainage of the obstructed macular area and improved vision within days. This study was aimed to evaluate the efficacy, visual outcome and complications following Nd:YAG laser hyaloidotomy for premacular subhyaloid hemorrhage. METHODS: Patients with premacular subhyaloid hemorrhage of more than 3 disc diameters (DD) of various etiologies, attending Tilganga Institute of Ophthalmology, Nepal from August, 2014 to February, 2015, were included. A comprehensive ocular evaluation was conducted and fundus photographs were taken to measure the size of the subhyaloid hemorrhage. Optical coherence tomography (OCT) were performed before and after treatment and on subsequent follow up visits. Fundus fluorescence angiography was done whenever necessary. Q switched Nd:YAG laser was applied to create an opening in the posterior hyaloids membrane for draining subhyaloid hemorrhage. The main outcome measures were success rate in performing hyaloidotomy, drainage of subhyaloid blood into vitreous cavity and its resorption, improvement in visual acuity, need for further intervention and postoperative complications. RESULTS: There were 21 eyes of 19 patients, 17(89.48%) male and 2(10.52%) female. In 3, premacular subhyaloid hemorrhage was bilateral. Mean age was 41.68 ± 17.08 years and a mean duration of symptoms 15.04 days. Mean pretreatment hemorrhage was 6.27DD. Nd:YAG laser hyaloidotomy was successful in 19 eyes(86.4%). In 2 patients, one each with Eales' disease and retinal vein occlusion the procedure was unsuccessful, necessitating pars plana vitrectomy, while in a case with proliferative diabetic retinopathy (PDR), vitrectomy was resorted for non clearing vitreous hemorrhage. Vision improved from a median of 3/60 pre-operatively to 6/6, at 6 months follow up. At 3 months, 2 patients with Eales' disease, one developed tractional detachment at macula while the other, an epiretinal membrane. No other complications were noted at 6 months. CONCLUSION: Nd:YAG laser hyaloidotomy is an inexpensive, effective and a safe outpatient procedure for premacular subhyaloid hemorrhage, producing rapid drainage with restoration of visual function avoiding more invasive procedures and enabling early assessment of the underlying retina. The final visual prognosis however, rests on the underlying cause of the subhyaloid hemorrhage and any accompanying retinal changes.

Intra- and inter-rater agreement between an ophthalmologist and mid-level ophthalmic personnel to diagnose retinal diseases based on fundus photographs at a primary eye center in Nepal: the Bhaktapur Retina Study.

BACKGROUND: Early detection can reduce irreversible blindness from retinal diseases. This study aims to assess the intra- and inter-rater agreement of retinal pathologies observed on fundus photographs between an ophthalmologist and two-mid level ophthalmic personnel (MLOPs). METHOD: A population-based, cross-sectional study was conducted among subjects 60 years and above in the Bhaktapur district of Nepal. Fundus photographs of 500 eyes of 500 subjects were assessed. The macula-centered 45-degree photographs were graded twice by one ophthalmologist and two MLOPs. Intra-rater and inter-rater agreements were assessed for the ophthalmologist and the MLOPs. RESULT: Mean age was 70.22 years ± 6.94 (SD). Retinal pathologies were observed in 55.6 % of photographs (age-related macular degeneration: 34.2 %; diabetic retinopathy: 4.2 %; retinal vein occlusion: 3.8 %). Twelve (2.4 %) fundus pictures were non-gradable. The intra-rater agreement for overall retinal pathologies, retinal hemorrhage, and maculopathy were substantial both for the ophthalmologist as well as for the MLOPs. There was moderate inter-rater agreement between the ophthalmologist and the first MLOP on second rating for overall retinal pathologies, [kappa (k); 95 % CI = 0.59 (0.51-0.66)], retinal hemorrhage [k; 95 % CI = 0.60 (0.41-0.78)], and maculopathy [k; 95 % CI = 0.52 (0.43-0.60)]. Inter-rater agreement between the ophthalmologist and the second MLOP for second rating was moderate for overall retinal pathologies [k; 95 % CI = 0.52 (0.44-0.60)], substantial agreement for retinal hemorrhage [k; 95 % CI = 0. 68 (0.52-0.84)], moderate agreement for maculopathy [k; 95 % CI = 0.59 (0.50-0.67)]. CONCLUSION: There is moderate agreement between the MLOPs and the ophthalmologist in grading fundus photographs for retinal hemorrhages and maculopathy.

Population awareness of diabetic eye disease and age related macular degeneration in Nepal: the Bhaktapur Retina Study.

BACKGROUND: Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are among the leading causes of visual impairment and blindness in developing countries. This study aims to explore the awareness of these retinal diseases in Nepal. METHOD: A population based cross-sectional study conducted among individuals 60 years and older from the Bhaktapur district of Nepal. One thousand consecutive subjects were enrolled and subjected to a structured questionnaire. RESULT: Subject age ranged from 60 to 93 years with a meanof 69.5 years ± 7.1(S.D.). Males and females comprised 45.1 and 55.9 % of the population, respectively. The majority was illiterate (78.2 %), and agriculture was the predominant occupation (79.8 %). 12.1 % were aware of the effect of diabetes on the eye, and among them, 99 % were aware that diabetes was a blinding disease caused by DR.11.5 % of the subjects were aware of DR, and 10.1 % were aware that subjects with diabetes should undergo periodic eye examinations. Only 7.6 % of subjects were aware of AMD.7.5 and 7.4 % were aware about its aggravation with smoking and sunlight exposure, respectively. Younger age group, males, literates, service holders, best corrected visual acuity >0.3 LogMAR, were each significantly associated with an increase in awareness of diabetic retinopathy. Smokers and those with agricultural occupations were less aware regarding AMD. Those with diabetes,with or without DRwere significantly more aware than those not having the disease. CONCLUSION: Among the Bhaktapur population, awareness of DR and AMD was only 11.5 and7.6 % respectively. Older age groups, females, illiterates, farmers, and those with poor visual acuity were less aware of these blinding diseases. We recommend community-based eye health education programs targeted at raising awareness of these diseases and preventive measures.

Clinical Characteristics of Proliferative Diabetic Retinopathy and Outcome of Pars Plana Vitrectomy in Proliferative Diabetic Retinopathy.

BACKGROUND: Proliferative diabetic retinopathy is a leading cause of blindness among people with diabetes. The study aimed to assess the clinical characteristics of proliferative diabetic retinopathy and outcome of pars plana vitrectomy in Proliferative diabetic retinopathy. METHODS: A prospective study was conducted from September 2019 to December 2021 among consecutive cases of proliferative diabetic retinopathy who underwent pars plana vitrectomy at a tertiary eye care center. Study was conducted after ethical approval from Institutional Review Committee. Detailed systemic and ocular history, visual acuity, ocular findings under mydriasis, surgical procedures, and outcome following pars plana vitrectomy were recorded. Cases were followed up regularly until one year after the pars plana vitrectomy. RESULTS: Total of 83 cases (89 eyes) of proliferative diabetic retinopathy were enrolled in the study. The mean age was 53 years ±9.7 SD, ranging from 26 years to 72 years. Males comprised of 62.7% cases. Type two diabetes comprised of 94% of cases. Indications for pars plana vitrectomy were; mixed vitreous hemorrhage and tractional retinal detachment (38.2%), non-clearing vitreous hemorrhage (38.1%), and tractional retinal detachment only (24.7%). Pre-operative intra-vitreal anti-vascular endothelial growth factor was given in 78.65% eyes and pan retinal photocoagulation in 58.42% eyes. The anatomical success was achieved in 95.5% eyes, visual improvement in 68.54%, static in 14.6% and worsened in 16.86% of eyes. About 15.7% of eyes had some form of post- operative complications. CONCLUSIONS: Vitreous hemorrhage with tractional retinal detachment, persistent vitreous hemorrhage and tractional retinal detachment involving macula were the common indication of pars plana vitrectomy among cases of Proliferative diabetic retinopathy. Anatomical success and visual acuity improvement can be achieved in majority of the eyes following PPV in Proliferative diabetic retinopathy.

Prevalence and pattern of vitreo-retinal diseases in Nepal: the Bhaktapur glaucoma study.

BACKGROUND: Vitreo-retinal diseases are among the leading causes of visual impairment and blindness worldwide. This study reports the prevalence and pattern of vitreo-retinal diseases in the Bhaktapur Glaucoma Study (BGS), a population based study conducted in Nepal. METHODS: BGS was a population based cross-sectional study involving 4800 subjects aged 40 years and over from Bhaktapur district. Subjects were selected using a cluster sampling methodology and a door-to-door enumeration. All subjects underwent a detailed ocular examination at the base hospital which included log MAR visual acuity, refraction, applanation tonometry and a dilated fundus examination. Fundus photography, optical coherence tomography and fundus fluorescein angiography were performed where indicated. RESULTS: Complete data was available for 3966 (82.62%) out of the total of 4800 enumerated subjects. The mean age was 55.08 years (SD 11.51). The overall prevalence of vitreo-retinal disorders was 5.35% (95% CI, 4.67 - 6.09). Increasing age was associated with a higher prevalence of vitreo-retinal disorders (P < 0.001). The prevalence of diabetes mellitus was 7.69% (95% CI, 6.88 - 8.56). Age-related macular degeneration (AMD) was the most common vitreo-retinal disorder with a prevalence of 1.50% (95% CI, 1.15 - 1.94), increasing significantly with age. The prevalence of diabetic retinopathy among the study population was 0.78% (95% CI, 0.53 - 1.11) and among the diabetic population 10.16% (95% CI, 7.01 - 14.12). The population prevalence of other retinal disorders were hypertensive retinopathy 0.88%, macular scar 0.37%, retinal vein occlusion 0.50%, macular hole 0.20%, retinitis pigmentosa 0.12%. and retinal detachment 0.10%.The prevalence of low vision and blindness due to vitreo-retinal disorders was 1.53% (95% CI, 1.18 - 1.97) and 0.65% (95% CI, 0.43 - 0.96), respectively. The prevalence of low vision and blindness was 28.77% (95% CI, 22.78-35.37) and 12.26% (95% CI, 8.17-17.45), respectively among cases with vitreo-retinal disorders. Blindness was observed to be unilateral in 19 cases (73%), and bilateral in 7 cases (27%). CONCLUSIONS: The prevalence of vitreo-retinal disorders in this Nepalese population was 5.35%, which increased significantly with age. AMD was the predominant retinal condition followed by diabetic retinopathy. One fourth of the subjects with vitreo-retinal disorder had low vision. Taking into consideration the aging population and emerging systemic diseases such as diabetes mellitus and hypertension, vitreo-retinal disorders could be of future public health importance.

A population-based survey of the prevalence and types of glaucoma in Nepal: the Bhaktapur Glaucoma Study.

OBJECTIVE: To determine the prevalence and types of glaucoma in a Nepalese population. DESIGN: Cross-sectional, population-based survey. PARTICIPANTS: A total of 4800 subjects aged 40 years or older from the Bhaktapur district of Kathmandu valley. METHODS: Subjects aged 40 years or older were selected using a cluster sampling procedure and door-to-door enumeration for a population-based, cross-sectional study. All subjects underwent a detailed ocular examination at the base hospital, which included logarithm of minimal angle of resolution visual acuity, refraction, applanation tonometry, gonioscopy, Lens Opacities Classification System II cataract grading, retinal examination, and Swedish Interactive Thresholding Algorithm standard perimetry when indicated. MAIN OUTCOME MEASURES: Diagnosis of glaucoma was based on criteria described by the International Society for Geographic and Epidemiological Ophthalmology. RESULTS: A total of 4003 subjects underwent a comprehensive eye examination (response rate 83.4%), and complete data were available in 3991 subjects. The mean intraocular pressure was 13.3 mmHg (97.5th and 99.5th percentiles, 18 and 20 mmHg, respectively), and the mean vertical cup-to-disc ratio was 0.26 (97.5th and 99.5th percentiles, 0.6 and 0.8 mmHg, respectively). There were 75 subjects with glaucoma, an age- and sex-standardized prevalence of 1.80 (95% confidence interval [CI], 1.68-1.92). Age- and sex-standardized prevalence was 1.24% (95% CI, 1.14-1.34) for primary open-angle glaucoma (POAG), 0.39% (95% CI, 0.34-0.45) for primary angle-closure glaucoma (PACG), and 0.15% (95% CI, 0.07-0.36) for secondary glaucoma. The prevalence of glaucoma increased with an increase in age with no significant difference in gender. Primary angle-closure glaucoma was 3 times more common in women. Nine eyes were blind, and 2 subjects were bilaterally blind from glaucoma. CONCLUSIONS: The overall prevalence of glaucoma was 1.9%. Of all glaucoma cases, POAG accounted for 68%, PACG accounted for 22.67%, and secondary glaucoma accounted for 9.33%. Among the subjects with POAG, 96.08% had not been previously diagnosed.

Comparison of central macular thickness between diabetic patients without clinical retinopathy and non-diabetic patients.

INTRODUCTION: Diabetic retinopathy (DR) is one of the leading causes of blindness in patients between 20 and 60 years of age which can be prevented by early detection of diabetic retinopathy. The duration of diabetes is probably the strongest predictor for development and progression of retinopathy. Optical Coherence Tomography (OCT) is a recent advance in imaging which is sensitive in early detection of small changes in macular thickness. MATERIALS AND METHODS: This hospital based cross-sectional study was done at a tertiary referral center in Kathmandu, Nepal where 364 eyes of 182 patients (182 eyes in 91 patients in each group diabetes without retinopathy group and nondiabetic group) were evaluated. Thickness of the macula was determined by using Spectral Domain Optical Coherence Tomography (SD- OCT) and compared between diabetic patients without clinical retinopathy and nondiabetic patients. RESULTS: The mean CMT as measured by Spectral Domain Optical Coherence Tomography in diabetic patients was 236.29±40.31 µm whereas it was 244.25±30.51 µm in non-diabetic cases. The mean central macular thickness of diabetic patients with duration of diabetes less than 1 year, 1-5 years, 6-10 years, 11-15 years and more than 15 years were 217.19±42.22, 233.49±45.69, 248.5±31.37, 250.89±21.62 and 240.75±11.26 respectively. CONCLUSIONS: This study concluded that in diabetic patients there was an initial decrease in central macular thickness which gradually increased with increasing duration of diabetes mellitus. Examination of macular thickness could be a useful modality to evaluate progression of disease before appearance of other clinical signs of diabetic retinopathy.

Prevalence of visual impairment, cataract surgery and awareness of cataract and glaucoma in Bhaktapur district of Nepal: the Bhaktapur Glaucoma Study.

BACKGROUND: Cataract and glaucoma are the major causes of blindness in Nepal. Bhaktapur is one of the three districts of Kathmandu valley which represents a metropolitan city with a predominantly agrarian rural periphery. This study was undertaken to determine the prevalence of visual impairment, cataract surgery and awareness of cataract and glaucoma among subjects residing in this district of Nepal. METHODS: Subjects aged 40 years and above was selected using a cluster sampling methodology and a door to door enumeration was conducted for a population based cross sectional study. During the community field work, 11499 subjects underwent a structured interview regarding awareness (heard of) and knowledge (understanding of the disease) of cataract and glaucoma. At the base hospital 4003 out of 4800 (83.39%) subjects underwent a detailed ocular examination including log MAR visual acuity, refraction, applanation tonometry, cataract grading (LOCSΙΙ), retinal examination and SITA standard perimetry when indicated. RESULTS: The age-sex adjusted prevalence of blindness (best corrected <3/60) and low vision (best corrected <6/18 ≥ 3/60) was 0.43% (95%C.I. 0.25 - 0.68) and 3.97% (95% C.I. 3.40 - 4.60) respectively. Cataract (53.3%) was the principal cause of blindness. The leading causes of low vision were cataract (60.8%) followed by refractive error (12%). The cataract surgical coverage was 90.36% and was higher in the younger age group, females and illiterate subjects. Pseudophakia was seen in 94%. Awareness of cataract (6.7%) and glaucoma (2.4%) was very low. Among subjects who were aware, 70.4% had knowledge of cataract and 45.5% of glaucoma. Cataract was commonly known to be a 'pearl like dot' white opacity in the eye while glaucoma was known to cause blindness. Awareness remained unchanged in different age groups for cataract while for glaucoma there was an increase in awareness with age. Women were significantly less aware (odds ratio (OR): 0.63; 95%, confidence interval (CI): 0.54 - 0.74) for cataract and (OR: 0.64; 95% CI: 0.50 - 0.81) for glaucoma. Literacy was also correlated with awareness. CONCLUSION: The low prevalence of visual impairment and the high cataract surgical coverage suggests that cataract intervention programs have been successful in Bhaktapur. Awareness and knowledge of cataract and glaucoma was very poor among this population. Eye care programs needs to be directed towards preventing visual impairment from refractive errors, screening for incurable chronic eye diseases and promoting health education in order to raise awareness on cataract and glaucoma among this population.

Rationale, methods and baseline demographics of the Bhaktapur Glaucoma Study.

BACKGROUND: To describe the methodology and baseline data of a population-based study designed to determine the prevalence of glaucoma and to study the risk factors for glaucoma development in a Nepali population. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Subjects 40 years and above residing in Bhaktapur District. PATIENTS AND METHODS: Power calculations suggest that a sample size of 4758 is required. Thirty clusters were randomly selected from the 2 municipalities and 16 Village Development Committees of Bhaktapur District in Nepal. A door-to-door census was conducted in the selected clusters to identify citizens 40 years of age and older. Demographic details were collected and a structured interview, regarding awareness for cataract and glaucoma was taken. All individuals fulfilling the eligibility criteria were recruited and referred to the Tilganga Institute of Ophthalmology in Kathmandu for a detailed clinical examination including glaucoma diagnostic procedures. Peripheral blood samples were taken to facilitate future genetic analysis. MAIN OUTCOME MEASURES: Prevalence of glaucoma, risk factors and genetic screening. RESULTS: A total of 4800 people were selected. The mean age of participants was 55.4 ± 12.3 years (range: 40-99) and 51.8% were female. In total, 64.8% of our cohort was aged less than 59 years and 60.5% were illiterate. Among the various ethnic races, 69.7% belonged to the Newar ethnic group. CONCLUSION: This study will determine the prevalence of glaucoma and allow for an increased understanding of the risk factors for glaucoma development in this region.

Agreement and Diagnostic Test Accuracy on Grading Diabetic Retinopathy Using Fundus Photographs by Allied Medical Personnel at a Community Diabetic Retinopathy Screening Program in Nepal.

Purpose: Diabetic retinopathy (DR) is a leading cause of blindness in low- and middle-income countries. This study aims to assess the agreement and diagnostic test accuracy of DR grading using fundus photographs by the allied medical personnel (AMP) as compared to ophthalmologist at DR screening program.Methods: Two 45 degree disc-centred and macula centred fundus photographs captured using digital fundus camera from 1344 eyes were graded by six AMP twice at three months and six months of training. DR grading was done using Early Treatment Diabetic Retinopathy Study criteria. Retina specialist grading was taken as the reference standard. Percentage agreement using kappa coefficient (k) and diagnostic test accuracy were assessed.Results: Intra-rater agreement of most AMP was almost perfect for detection of any DR and vision-threatening diabetic retinopathy (VTDR) at three and six months. Inter-rater agreement at 3 months at second grading was substantial for any DR (k = 0.62; 95% confidence interval (CI): 0.67-0.68) and VTDR (k = 0.63; 95% CI: 0.47-0.75). Inter-rater agreement in 6 months at second grading was also substantial for any DR (k = 0.66; 95% CI: 0.61-0.71) and VTDR (k = 0.64; 95% CI: 0.52-0.75). The sensitivity and specificity for any DR at second grading in 3 months was 94.99% and 63.97% and at 6 months was 95.55% and 66.91%, respectively.Conclusion: The inter-rater agreement of AMP as compared to ophthalmologists for any DR or VTDR was substantial at both 3 and 6 months. AMP can support as first-level DR graders for timely referral and treatment of VTDR.

Demographic characteristics, patterns and risk factors for retinal vein occlusion in Nepal: a hospital-based case-control study.

PURPOSE: Retinal vein occlusion (RVO) is an increasing problem leading to visual impairment in Nepal. Our study investigates the demographic characteristics, patterns and risk factors for RVO in this developing Asian country. METHODS: This is a hospital-based case-control study conducted at the Tilganga Institute of Ophthalmology of Nepal during the period of January 2007 to January 2008. All consecutive new cases of RVO diagnosed at the Institute were included. Cases with intraocular inflammation or a prior history of intraocular injections, laser therapy or vitrectomy for RVO were excluded from the study. Age, sex and geographically matched subjects were recruited as a control group from patients who presented for regular eye examinations at the same hospital during the study period. RESULTS: A total of 218 patients with RVO presented during the study period. The mean age of the patients was 61.1 + or - 12.3 years with more men (58.3%) than women. The mean age for control groups was 61.3 + or - 13.0 years. Seventy per cent of subjects had branch retinal vein occlusion, whereas central retinal vein occlusion was present in 26.6%. 63.9% of branch retinal vein occlusion was found in the superotemporal branch. Hypermetropia, primary open angle glaucoma, hypertension, mixed diabetes and hypertension, and heart disease were significantly higher in RVO cases as compared with the control group. CONCLUSION: The demographic characteristics, patterns and risk factors of RVO in Nepal can help guide interventions against these blinding diseases in similar developing countries.

Agreement on Grading Retinal Findings of Patients with Diabetes Using Fundus Photographs by Allied Medical Personnel when Compared to an Ophthalmologist at a Diabetic Retinopathy Screening Program in Nepal.

INTRODUCTION: Diabetic retinopathy (DR) is the emerging cause of blindness in developing countries. This study aimed to assess the accuracy of grading retinal findings of patients with diabetes using fundus photographs by allied medical personnel (AMP) when compared to an ophthalmologist. MATERIALS AND METHODS: Six AMPs were enrolled for grading fundus photographs of patients with diabetes after three and six months of training twice at two weeks interval. The total number of fundus photographs graded were 1,344. Grading by a retina specialist was used as the gold standard. Intra-rater and inter-rater agreement was assessed using the kappa coefficient (k). RESULTS: The intra-rater agreement of half of the AMPs in both three months and six months was almost perfect for grading of any retinal abnormalities, and substantial for retinal hemorrhages. In three months, the overall inter-rater agreement at the second rating was moderate for any retinal abnormalities (k=0.60) and retinal hemorrhage (k=0.48) and was fair for macular exudates (k=0.35). The overall inter-rater agreement of AMPs in six months at the second rating was substantial for any retinal abnormalities (k=0.61), fair for retinal hemorrhage (k=0.30), and moderate for macular exudates (k=0.49). The overall inter-rater agreement at first rating was almost similar to the second rating in both three months and six months. CONCLUSION: Intra-rater agreement of AMPs was almost perfect for any retinal abnormalities and substantial for retinal hemorrhage. The inter-rater agreement of AMP was substantial for any retinal abnormalities and moderate for retinal hemorrhages and macular exudates. The agreement results were almost similar at three months and six months. AMPs could be utilized in screening of DR and other retinal pathologies for timely referral to reduce the blindness in low-resource settings.

Inherited Macular Dystrophies in a Tertiary Care Centre.

BACKGROUND: Inherited macular dystrophies constitute a group of diseases characterized by bilateral central visual loss with symmetrical macular abnormalities usually presenting in the first two decades of life. The aim of this study were to find out the demographic characteristics and disease pattern of inherited retinal dystrophies in subjects attending retina outpatient department in a tertiary care center. METHODS: An observational study among twenty-six participants diagnosed as macular dystrophy visiting a tertiary care centre in Nepal, during January 2018 to June 2018 were included in the study. Detailed history, slit lamp examination, dilated fundus examination, coloured fundus photography, full field electroretinogram, multifocal electroretinogram, automated visual field and colour vision were done. RESULTS: A total of 52 eyes of 26 subjects were diagnosed with macular dystrophy. The male to female ratio was 1:1. The mean age of presentation was 28.38 years. Most common symptom was blurring of vision seen in 96.15%.The mean visual acuity was 0.67 log mar units in right eye and 0.71 log mar units in the left eye. The most common macular dystrophy was cone dystrophy followed by adult vitelliform macular dystrophy and Stargardts dystrophy. CONCLUSIONS: Cone dystrophy is the most common followed by Stargardt's disease and adult vitelliform macular dystrophy. Most presented in the first two decades of life and the most common presenting symptom was blurring of vision.

A Study on Pattern of Retinal Detachment in Patients with Choroidal Coloboma and Its Outcome after Surgery at a Tertiary Eye Hospital in Nepal.

BACKGROUND: To review the pattern of retinal detachment (RD) in patients with choroidal coloboma and type of reattachment surgery performed and to study its outcome in terms of retinal reattachment, visual acuity, and postsurgical complications. METHODS: Observational case series of a single tertiary eye institution of 13 eyes having choroidal coloboma with RD done from January 2015 to June 2017. RESULTS: Mean age of presentation was 29.3 years (Range 14-60 years). Males were two times more affected than females (2.25 : 1). The overall rate of anatomic success achieved after RD repair and silicon oil removal at 6 months was 92.3% (12/13 eyes). Following surgery, visual acuity improved in 6 out of 11 eyes (54.54%), remained unchanged in 4 eyes (36.36%), and worsened in 1 eye (9.1%). The most common complication following surgery was secondary glaucoma in 30.7% (4/11 eyes). CONCLUSION: The overall anatomic success rate of retina reattachment surgery in colobomatous eye is good, and the visual outcome following surgery can improve in majority of the cases or may remain same in few cases. Hence, timely surgery is advocated. But careful follow-up is required as the risk of postoperative complications is also high.

Pattern and Presentation of Vitreo-Retinal Diseases: An Analysis of Retrospective Data at a Tertiary Eye Care Center in Nepal.

PURPOSE: We examined patients presenting in a tertiary eye hospital in Nepal, focusing on information relevant to screening and management programs for vitreo-retinal (VR) disease. DESIGN: Retrospective, cross-sectional study. METHODS: We reviewed all patients presenting for the first time to the VR-clinic over 1 year. We quantified patient demography, symptoms and duration, systemic diseases, ophthalmological examinations, diagnostic investigations, and final diagnoses. RESULTS: Of the 1905 cases, 1148 were male (60.3%). The 25th percentile of ages was 29 and 38 years for male and female, respectively; thus, female presented later (P < 0.0001). Hypertension was the commonest systemic disease (40.8%), followed by diabetes (32.5%). Age-related macular degeneration (AMD) and diabetic retinopathy (DR) affected 447 eyes (11.8%) and 416 eyes (10.9%), respectively. Male and female AMD and DR patients did not differ in age or disease duration. Similarly, age or disease duration for DR did not correlate with severity. Asymmetry of disease severity between eyes with AMD and DR was largest in patients with 1 normal eye. Presenting acuity was asymmetric between eyes (P < 0.0001) with people more often reporting once their right eyes had acuity of 6/18 or worse. CONCLUSIONS: The screening of blood pressure and glucose levels combined with fundus photography could prevent many from progressing to life-changing visual impairment and blindness. Later reporting by females began at childbearing age; therefore, education and ocular screening could be usefully coupled in reproductive health programs. Clubbing VR disease screening with other established health programs like diabetes control program, hypertension clinics, school health program, and so on, would provide economical and sustainable approach.

Prevalence and Severity of Diabetic Retinopathy among Diabetic Patients Presenting to a Tertiary Eye Hospital in Nepal.

PURPOSE: The purpose of the study is to evaluate the prevalence and severity of diabetic retinopathy (DR) among all diabetic patients presenting to a tertiary eye care center in Nepal over a 3-year period. MATERIALS AND METHODS: This was a retrospective review of all clinical records from the initial presentations of diabetic patients at the Tilganga Institute of Ophthalmology (TIO) from 2012 to 2014. RESULTS: In total, 8855 patients were identified who presented to TIO with a prior diagnosis of diabetic mellitus (DM) during the study period. DR was found in 1714 patients (19.4%) at the time of initial presentation, 1305 (14.7%) of which had nonproliferative DR (PDR), while 617 (6.9%) demonstrated diabetic macular edema (DME) and 409 (4.6%) demonstrated PDR. Of the 1714 patients with DR, 825 (48.1%) required treatment at initial presentation for DME and/or PDR. Male gender, hypertension, age at presentation, and interval from diagnosis of DM to initial eye consultation were significantly associated with the presence of DR (P < 0.05). CONCLUSIONS: The prevalence of DR among patients with DM was 19.4%, which is lower than previously published estimates. However, among patients diagnosed with DR, over half presented with a vision-threatening complication warranting some measure of initial treatment.