Rajiv Khandekar

Recurrence of trichiasis: A long-term follow-up study in the Sultanate of Oman

BACKGROUND. The prevalence of long-term trichiasis recurrence following tarsal rotation and electro-epilation procedures has not been determined. A non-concurrent prospective study of surgical cases of trichiasis was therefore undertaken in Oman. METHODS. A sample of 603 surgical cases of trichiasis (approximately half tarsal rotation and half electro-epilation) was followed for an average of 3.1 years to determine recurrence. Recurrence was defined as either mild (<5 lashes touching the globe) or severe (5 or more lashes touching the globe). RESULTS. Overall, 56% (95% confidence interval of 50.6%–61.0%) of all surgical cases recurred; ranging from 61.8% of tarsal rotation patients to 50.6% of electro-epilation patients. Severe recurrence was detected among 27% of tarsal rotation patients and 10% of electro-epilation patients. Recurrence was associated with female sex, residence in a high-risk region, and time since surgery. DISCUSION. The risk of recurrence after electro-epilation and bilamellar tarsal rotation surgery is high; strategies that account for recurrence need to be introduced.

The prevalence and causes of blindness in the Sultanate of Oman: the Oman Eye Study (OES)

Aims: To estimate the magnitude and the causes of blindness through a community based nationwide survey in Oman. This was conducted in 1996–7. Methods: A stratified cluster random sampling procedure was used to select 12 400 people. The WHO/PBD standardised survey methodology was used, with suitable adaptation. The major causes of blindness were identified among those found blind. Results: A total of 11 417 people were examined (response rate 91.8%) The prevalence of blindness in the Omani population was estimated to be 1.1% (95% CI 0.9 to 1.3), blindness being defined according to the WHO Tenth Revision of the International Classification of Diseases. Prevalence of blindness was clearly related to increasing age, with estimates of 0.08% for the 0–14 age group, 0.1% for the 15–39 age group, 2.3% for the 40–59 age group, and 16.8% for the group aged 60 +. There was a statistically significant difference between the prevalence in females (1.4%) and males (0.8%). The northern and central regions had a higher prevalence of blindness (1.3% to 3%). The major causes of blindness were unoperated cataract (30.5%), trachomatous corneal opacities (23.7%), and glaucoma (11.5%) Conclusions: Despite an active eye healthcare programme, blindness due to cataract and trachoma remains a public health problem of great concern in several regions of the sultanate. These results highlight the need, when planning effective intervention strategies, to target the eye healthcare programme to the ageing population, with special emphasis on women.

Diabetic retinopathy in Oman: a hospital based study

The magnitude of diabetic retinopathy, its determinants, and coverage of laser treatment for diabetic retinopathy among registered people with diabetes in Oman are presented. 2249 randomly selected subjects representing 5564 registered diabetics were examined. WHO recommended definitions of diabetes, retinopathy, and other related conditions were used. Physicians reported the profile of the diabetes while ophthalmologists reported ocular profile and the eye care provided to them. The prevalence of diabetic retinopathy was 14.39% (95% CI 13.46 to 15.31). Men had significantly higher rate of retinopathy than women. The retinopathy rate was higher in age groups 50–59 years and 60–69 years. The rates of background retinopathy, proliferative retinopathy, and diabetic maculopathy were 8.65%, 2.66%, and 5.12%, respectively. The rate was higher among subjects with longer duration of diabetes than those with a shorter duration. Those with an HbA1c level more than 9% had significantly higher rates of diabetic retinopathy than those with an HbA1c level less than 9%. The retinopathy rate was higher in cases with hypertension, nephropathy, and neuropathy. Of those with diabetic retinopathy who were advised to have treatment at the time of registration, only 20% were treated with laser therapy.

Prevalence of uncorrected refractive error and other eye problems among urban and rural school children

Background: Uncorrected refractive error is an avoidable cause of visual impairment. Aim: To compare the magnitude and determinants of uncorrected refractive error, such as age, sex, family history of refractive error and use of spectacles among school children 6-15 years old in urban and rural Maharashtra, India. Study Design: This was a review of school-based vision screening conducted in 2004-2005. Materials and Methods: Optometrists assessed visual acuity, amblyopia and strabismus in rural children. Teachers assessed visual acuity and then optometrists confirmed their findings in urban schools. Ophthalmologists screened for ocular pathology. Data of uncorrected refractive error, amblyopia, strabismus and blinding eye diseases was analyzed to compare the prevalence and risk factors among children of rural and urban areas. Results: We examined 5,021 children of 8 urban clusters and 7,401 children of 28 rural clusters. The cluster-weighted prevalence of uncorrected refractive error in urban and rural children was 5.46% (95% CI, 5.44-5.48) and 2.63% (95% CI, 2.62-2.64), respectively. The prevalence of myopia, hypermetropia and astigmatism in urban children was 3.16%, 1.06% and 0.16%, respectively. In rural children, the prevalence of myopia, hypermetropia and astigmatism was 1.45%, 0.39% and 0.21%, respectively. The prevalence of amblyopia was 0.8% in urban and 0.2% in rural children. Thirteen to 15 years old children attending urban schools were most likely to have uncorrected myopia. Conclusion: The prevalence of uncorrected refractive error, especially myopia, was higher in urban children. Causes of higher prevalence and barriers to refractive error correction services should be identified and addressed. Eye screening of school children is recommended. However, the approach used may be different for urban and rural school children.

Diabetic retinopathy, visual impairment and ocular status among patients with diabetes mellitus in Yemen: A hospital-based study

Background: We present a series of patients with diabetes mellitus (DM) who attended an eye hospital in Sana, Yemen during 2004. Aim: To determine the magnitude and risk factors of diabetic retinopathy (DR). Design: Cross-sectional study. Materials and Methods: Ophthalmologists assessed vision, ocular pressure, ocular media and posterior segment to note ocular manifestations among patients with DM. DR was graded by using bio-microscope and Volk lens. The prevalence and 95% confidence interval of ocular complications of DM were calculated. Risk factors of DR like age, sex, duration of diabetes and hypertension were evaluated. Statistical Analysis: Univariate and multivariate analysis. Results: Our series comprised 350 patients suffering from DM. The duration of diabetes was ≥15 years in 101 (29%) patients. Physician was treating 108 DM patients with insulin. The prevalence of DR was 55% (95% CI 49.6–60.1). The proportions of background diabetic retinopathy (BDR), preproliferative diabetic retinopathy (PPDR), proliferative diabetic retinopathy (PDR) and diabetic macular edema were 20%, 13%, 17% and 22% respectively. The prevalence of blindness among DM patients was 16%. The prevalence of cataract and glaucoma was 34.3% and 8.6%. Duration of DM was the predictor of DR. One-fifth of the patients had sight-threatening DR and needed laser treatment. Conclusions: DR was of public health magnitude among our patients. An organized approach is recommended to address DR in the study area.

Regular Visits to a Diabetes Clinic Were Associated with Lower Magnitude of Visual Disability and Diabetic Retinopathy—A Hospital-Based Historical Cohort Study in Yemen

BACKGROUND We associated regularity in visits to a diabetes clinic with the presence of diabetic retinopathy (DR) and visual disabilities. METHODS This historical cohort study was conducted in 2004. The physician reported details of diabetes mellitus (DM), hypertension, and other illness. The ophthalmologist examined eyes and noted visual acuity, DR, and other ocular morbidities. We calculated the relative risk (RR) of different complications of diabetes. RESULTS Our cohort consisted of 228 patients (114 in each group, one that attended diabetes clinics regularly [group A] and one that had irregular attendance [group B]). DR was found in 47 (41.2%) and 68 (61.4%) patients, respectively. The risk of DR was significantly higher in group B (RR = 1.51, 95% confidence interval [CI] 1.23 to 2.18). The severity of DR was also positively associated with irregularity in clinic visits (x(2) = 33.56, degrees of freedom = 5, P = 0.000003). The risk of bilateral blindness (RR = 4.0, 95% CI 1.38 to 11.6) and low vision disability (RR = 2.53, 95% CI 1.84 to 3.47) were higher in group B. The duration of diabetes and the regularity in clinic visits were the predictors of DR. CONCLUSIONS The presence of DR and visual disabilities among patients with diabetes is associated with irregular attendance at diabetes clinics. The regularity of medical visits seems to be a proxy indicator of better primary prevention of eye complications of DM.

Prevalence and Causes of Blindness & Low Vision; Before and Five Years After ‘VISION 2020’ Initiatives in Oman: A Review

Background: A prevalence survey of blindness and low vision was conducted in Oman in 2005. Here, we present the prevalence and determinants of blindness and low vision among the population ≥ 40 years of age. The results are then compared with those of the survey in 1997 and the changes following the ‘VISION 2020’ initiatives are assessed. Methods: The survey covered 24 randomly selected clusters (75 houses in each). Teams assessed the distance vision of subjects while wearing glasses. The ophthalmologists examined the anterior segment and fundus to determine the causes of disability. The visual field was tested in those suspected of glaucoma. The prevalence rates of blindness (< 3/60 on presentation), legal blindness (< 6/60) and low vision (< 6/18) were calculated. The data from the 1997 survey was then analyzed to obtain similar rates in the population ≥ 40 years of age. Results: The prevalence of blindness was 8.25% (95% CI 7.14–9.36) in the ≥ 40 year-old population in 2005. The rate would be 6.95% (95% CI 5.92–7.98) if blindness were defined as vision with best possible correction. The prevalence of legal blindness and low vision were 12% and 45.12%, respectively. In the 1997 survey, the prevalence of blindness in same age group was 7.23% (95% CI 5.91–8.55). Between the two surveys, the prevalence of blindness due to corneal pathology declined from 1.9% to 1.1% but that of blindness due to unoperated cataract increased from 1.8% to 2.3%. Conclusions: The rate of disability has declined but the number of blind people has increased in Oman. The causes of blindness have changed from communicable/avoidable eye diseases to non-curable/chronic eye diseases, and the number with visual disabilities has increased. An increasing number of operations for cataract and improvements in the care for glaucoma and diabetic retinopathy are recommended.

Impact of Face Washing and Environmental Improvement on Reduction of Active Trachoma in Vietnam—A Public Health Intervention Study

Purpose: A public health intervention study in Vietnam was conducted between 2002 and 2005 to assess the impact of improved water and sanitation facilities and increased awareness about active trachoma in the community. Methods: In My Thon village (MT), all four components of the SAFE strategy were implemented. In Xom Ngoai village (XN), only the S & A components of the trachoma control strategy were implemented. The villagers improved water and sanitation facilities in MT. Womens Union and school authorities assisted in increasing awareness in the community. Ophthalmologists examined the residents for trachoma. The decline in active trachoma and other water-related diseases was determined by pre- and post-intervention assessments. The impact of the differential F & E strategy on two villages was evaluated. Results: The active trachoma prevalence in MT (SAFE) and XN (SA) at baseline was 13.3% and 10.2%, respectively. In two years, the masons constructed or improved 281 double-vault and three septic tank latrines, 241 bathrooms, 273 dug wells and 252 water tanks in MT. The prevalence in MT (SAFE) & XN (SA) after two years was 1.4% and 6.7%, respectively. The additional decline of active trachoma due to the differential F & E strategy among children under the age of 15 was 6.8%. The F & E strategy was responsible for 58.7% of the decline at all ages and 37.4% in children under the age of 15. Knowledge of the prevention of trachoma had improved in two years. However, the attitude towards and practice of trachoma control were not different in the two villages. Conclusions: ‘F’ & ‘E’ implementation made a significant contribution to the reduction of active trachoma. Community participation and collaborative efforts of partners are crucial. The indicators used to monitor F & E strategies are interrelated and therefore should be evaluated together.

Prevalence and Causes of Blindness, Low Vision and Status of Cataract in 50 Years and Older Citizen of Qatar—A Community Based Survey

Background: Rapid Assessment for the Avoidable Blindness (RAAB) was conducted in Qatar during 2009. We present the prevalence and determinants of visual disabilities and status of cataract among citizens aged 50 years and older. Methods: Residents of randomly selected houses and clusters participated in the survey. Opticians noted the presenting and the best corrected vision of participants from 49 clusters. Ophthalmologists examined participants with additional instruments like bio-microscope, digital camera, auto-perimeter and auto-refractor in a mobile van. World Health Organization recommended principal cause of blindness (Visual acuity [VA] < 3/60 in better eye), Severe visual impairment (SVI) (<6/60), low vision (VA < 6/18) and unilateral blindness (VA < 3/60) were designated. Persons with VA < 6/18 and cataract were interviewed to calculate coverage and barriers for cataract surgeries. Age sex adjusted prevalence of visual disabilities and their 95% Confidence Intervals (CI) were estimated. Results: We examined 2,433 (97.3%) participants. The age sex adjusted prevalence of bilateral blindness was 1.28% [95% CI 1.22–1.35], SVI (1.67%), low vision (3.66%) and unilateral blindness (3.61%) in 50 years and older population. Female and older age groups were significant risk factors of visual disabilities. Cataract and glaucoma were the main causes of visual disabilities. The coverage of cataract services was 68.2%. Believing that cataract as an aging process (25) and adequate vision in the fellow eye (15) were the reasons for delay in surgery. Conclusions: To reduce avoidable blindness, un-operated cataract should be addressed. Primary and secondary eye care systems should be strengthened to improve the care of blinding eye diseases in Qatar.

One year recurrence of trachomatous trichiasis in routinely operated Cuenod Nataf procedure cases in Vietnam

Background: Recurrence of trichiasis following surgery remains unacceptably high, regardless of the surgical procedure. Few prospective studies of sufficient size are available to assess the rate of recurrence and the factors contributing to recurrence. A prospective study of the modified Cuenod Nataf surgical procedure was conducted in Vietnam to determine recurrence and co-factors. Methods: The prospective study of Cuenod Nataf surgery for trachomatous trichiasis took place in four districts of Vietnam. All patients from identified villages who had surgery were followed for a period of 1 year. 10 Surgeons using standard techniques and recording procedures carried out the surgery. The presence of an eyelash touching the eyeball in the operated eye was considered as recurrence. Information on all subjects was recorded preoperatively, intraoperatively, and postoperatively. An independent examiner recorded postoperative information. Relative risks were calculated to assess the contribution of various risk factors to recurrence (by eye and by person). Cox proportional hazards modelling was used to assess the independent contribution of relevant factors to the outcome. Results: 471 individuals had trichiasis surgery; 463 were followed for a period of 1 year. Overall, the recurrence rate was 10.8% (95% CI 8.0 to 13.6). Among people having surgery recurrence (one or both eyes) was most common in the most elderly (relative risk (RR) 2.49) and among those with a history of previous surgery (RR = 2.49). Cox proportional hazards analysis (by eye) revealed that visual acuity, conjunctival scarring, and suture adjustment were associated with recurrence at 1 year. Conclusion: The Cuenod Nataf procedure, which is well accepted in the community and by eye care providers in Vietnam, has an acceptable 1 year success rate. Individuals with severe conjunctival scarring have the highest rate of recurrence suggesting that other surgical approaches are needed to manage these patients or that these patients need to be educated regarding the risk of recurrence. Active follow up of these patients would be warranted. The association with suture adjustment requires further investigation.