Sannapaneni Krishnaiah

Clinical outcomes of xeno-free autologous cultivated limbal epithelial transplantation: a 10-year study

Purpose Ocular burns can damage the corneal epithelial stem cells located at the limbus. This study evaluated the efficacy of xeno-free autologous cell-based treatment of limbal stem cell deficiency. Methods This retrospective study included 200 patients, above 8 years of age, with clinically diagnosed unilateral total limbal stem cell deficiency due to ocular surface burns treated between 2001 and 2010. A small limbal biopsy was obtained from the unaffected eye. The limbal epithelial cells were expanded ex vivo on human amniotic membrane for 10–14 days using a xeno-free explant culture system. The resulting cultured epithelial monolayer and amniotic membrane substrate were transplanted on to the patients affected eye. Postoperative corneal surface stability, visual improvement and complications were objectively analysed. Results A completely epithelised, avascular and clinically stable corneal surface was seen in 142 of 200 (71%) eyes at a mean follow-up of 3±1.6 (range: 1–7.6) years. A two-line improvement in visual acuity, without further surgical intervention, was seen in 60.5% of eyes. All donor eyes remained healthy. Conclusions Autologous cultivated limbal epithelial transplantation using a xeno-free explant culture technique was effective in long-term restoration of corneal epithelial stability and improvement of vision in eyes with ocular surface burns.

Prevalence and risk factors for refractive errors in the South Indian adult population: The Andhra Pradesh Eye disease study

Aim: To report the prevalence, risk factors and associated population attributable risk percentage (PAR) for refractive errors in the South Indian adult population. Methods: A population-based cross-sectional epidemiologic study was conducted in the Indian state of Andhra Pradesh. A multistage cluster, systematic, stratified random sampling method was used to obtain participants (n = 10293) for this study. Results: The age-gender-area-adjusted prevalence rates in those ≥40 years of age were determined for myopia (spherical equivalent [SE] < −0.5 D) 34.6% (95% confidence interval [CI]: 33.1–36.1), high-myopia (SE < −5.0 D) 4.5% (95% CI: 3.8–5.2), hyperopia (SE > +0.5 D) 18.4% (95% CI: 17.1–19.7), astigmatism (cylinder < −0.5 D) 37.6% (95% CI: 36–39.2), and anisometropia (SE difference between right and left eyes >0.5 D) 13.0% (95% CI: 11.9–14.1). The prevalence of myopia, astigmatism, high-myopia, and anisometropia significantly increased with increasing age (all p < 0.0001). There was no gender difference in prevalence rates in any type of refractive error, though women had a significantly higher rate of hyperopia than men (p < 0.0001). Hyperopia was significantly higher among those with a higher educational level (odds ratio [OR] 2.49; 95% CI: 1.51–3.95) and significantly higher among the hypertensive group (OR 1.24; 95% CI: 1.03–1.49). The severity of lens nuclear opacity was positively associated with myopia and negatively associated with hyperopia. Conclusions: The prevalence of myopia in this adult Indian population is much higher than in similarly aged white populations. These results confirm the previously reported association between myopia, hyperopia, and nuclear opacity.

Barriers to accessing eye care services among visually impaired populations in rural Andhra Pradesh, South India.

Purpose: To understand the reasons why people in rural south India with visual impairment arising from various ocular diseases do not seek eye care. Materials and Methods: A total of 5,573 persons above the age of 15 were interviewed and examined in the South Indian state of Andhra Pradesh covering the districts of Adilabad, West Godavari and Mahaboobnagar. A pre-tested structured questionnaire on barriers to eye care was administered by trained field investigators. Results: Of the eligible subjects, 1234 (22.1%, N=5573)) presented with distant visual acuity < 20/60 or equivalent visual field loss in the better eye. Of these, 898 (72.7%, N=1234) subjects had not sought treatment despite noticing a decrease in vision citing personal, economic and social reasons. The analysis also showed that the odds of seeking treatment was significantly higher for literates [odds ratio (OR) 1.91, 95% confidence interval (CI) 1.38 to 2.65], for those who would be defined as blind by visual acuity category (OR 1.35, 95% CI 0.96 to 1.90) and for those with cataract and other causes of visual impairment (OR 1.50, 95% CI 1.11 to 2.03). Barriers to seeking treatment among those who had not sought treatment despite noticing a decrease in vision over the past five years were personal in 52% of the respondents, economic in 37% and social in 21%. Conclusion: Routine planning for eye care services in rural areas of India must address the barriers to eye care perceived by communities to increase the utilization of services.

Awareness of glaucoma in the rural population of Southern India

PURPOSE To explore the awareness of glaucoma amongst the rural population of Andhra Pradesh, India. MATERIALS AND METHODS A total of 7775 subjects of all ages, representative of the rural population of Andhra Pradesh, participated in the Andhra Pradesh Eye Disease Study. The responses of subjects older than 15 years (n=5573) who completed a structured questionnaire regarding awareness (heard of glaucoma) and knowledge (understanding of disease) of glaucoma formed the basis of this study. RESULTS Awareness of glaucoma (n=18; 0.32%) was very poor in this rural population, and females were significantly less aware (p=0.007). Awareness of glaucoma was also significantly less among illiterate persons (p<0.0001), and socially backward population (p<0.0001). Majority of the respondents who were aware of glaucoma (n=10; 55.6%) did not know if visual loss due to glaucoma was permanent or reversible. The major source of awareness of glaucoma in this population was TV/magazines and other media followed by information from a relative or acquaintance suffering from the disease. CONCLUSION Awareness of glaucoma is very poor in the rural areas of southern India. The data suggest the need for community-based health education programmes to increase the level of awareness and knowledge about glaucoma.

Orbital Cysticercosis: Clinical Manifestations, Diagnosis, Management, and Outcome

PURPOSE To describe the clinical manifestations, diagnosis, management, and outcome of orbital cysticercosis in a tertiary eye care center in Southern India. DESIGN Retrospective observational case series. PARTICIPANTS A total of 171 patients with orbital cysticercosis. METHODS Retrospective case series involving consecutive patients with orbital cysticercosis from March 1990 to December 2001. MAIN OUTCOME MEASURES Clinical resolution and significant residual deficit. RESULTS The median age at presentation was 13 years (range 2-65 years), and 93 patients (54.4%) were male. The 3 main symptoms at presentation were periocular swelling (38%), proptosis (24%), and ptosis (14%) with a median duration of 2 (range 0-24) months. The 3 main signs at presentation included ocular motility restriction (64.3%), proptosis (44.4%), and diplopia (36.8%). The cyst locations in the decreasing order of frequency were anterior orbit (69%), subconjunctival space (24.6%), posterior orbit (5.8%), and the eyelid (0.6%). In all, 80.7% of patients had cysts in relation to an extraocular muscle. The superior rectus (33.3%) was the most commonly involved extraocular muscle. Contact B-scan ultrasonography was diagnostic of cysticercosis in 84.4% of patients. Orbital cysticercosis was managed medically in 158 of 166 patients. Although 149 patients received a combination of oral albendazole and prednisolone, 1 patient received oral albendazole alone, 7 patients received oral prednisolone alone, and 1 patient received oral praziquantel. Surgery was performed in 8 patients. Clinical resolution was seen in 128 of 138 patients (92.8%) at 1 month and 81 of 85 patients (95.3%) at 3 months. A significant residual deficit was present in 29 of 138 patients (21.0%) at the final follow-up and included proptosis in 7 patients, ptosis in 6 patients, ocular motility restriction in 3 patients, diplopia in 2 patients, strabismus in 2 patients, and a combination of the above in 9 patients. CONCLUSIONS Orbital cysticercosis is a common clinical condition in the developing world. It typically affects young individuals and has a wide spectrum of clinical manifestations. Both B-scan ultrasonography and computed tomography scan are useful in confirming the diagnosis. Despite resolution of cysticercosis with medical management, a significant proportion of patients may have residual functional deficits.

Outcome of penetrating keratoplasty for Peters anomaly.

Purpose: To determine the results of corneal graft survival after penetrating keratoplasty for Peters anomaly. Methods: Retrospective review of records of children 12 years of age or younger who underwent penetrating keratoplasty for Peters anomaly between March 1988 and December 2003. The data were analyzed regarding graft survival. The survival probabilities were estimated by using the Kaplan-Meier method. The main outcome measure was graft clarity. Results: Forty corneal transplants were performed in 32 children with Peters anomaly whose mean age at keratoplasty was 8.6 ± 3.9 months (range, 2.5-22 months). The mean follow-up period was 1.9 ± 2.9 years (range, 1 month to 15 years). Seventeen (42.5%) of the 40 grafts retained full clarity. Survival analysis showed a 52% probability of the graft remaining clear at the end of 6 months, which dropped to 22% at 2 years. The predicted mean survival time of grafts was 20.1 months (95% confidence interval, 4.9-36.3). Allograft rejection was the most frequently identified cause of graft failure, accounting for 15 (65%) of the 23 failed grafts, with 93.3% of episodes occurring in the first year. Poor graft survival correlated with age younger than 6 months (P = 0.04). Conclusions: The overall probability of maintaining a clear corneal transplant in Peters anomaly is 22% at 2 years and may be adversely affected by younger age at surgery. Because most episodes of rejection occurred in the first year, follow-up is recommended during this period.

Visual outcomes of bilateral congenital and developmental cataracts in young children in south India and causes of poor outcome

Context: Bilateral pediatric cataracts are important cause of visual impairment in children. Aim: To study the outcome of bilateral pediatric cataract surgery in young children. Setting and Design: Retrospective case series in a tertiary center. Materials and Methods: Records of pediatric cataracts operated between January 2001 and December 2003, with a minimum follow-up of 3 months, were reviewed retrospectively. Statistical Methods: Independent sample t-test, Fishers exact test, and logistic regression using SPSS (Statistical Package for Social Science, Chicago, USA) version 12. Results: 215/257 (83.7%) patients had a minimum follow-up of 3 months. The mean age of presentation to the hospital was 53 months (range: 0-168 months). Congenital cataract was present in 107 patients (58.2%) and developmental cataract in 77 patients (41.8%). The mean age at surgery was 55.2 months (range: 1-168 months). Out of 430 eyes, 269 (62.6%) had an intraocular lens implanted. The mean duration of follow-up was 13.1 months (range: 3-38 months). Pre-operatively, 102 patients (47.3%) had visual acuity <6/60, in the better eye, compared to 37 patients (17.2%) post-operatively (P < 0.001). Eighty-five patients (39.5%) had visual acuity >6/18. The most common early post-operative complication was fibrinous uveitis in 57 eyes (13.3%) and the most common delayed post-operative complication was posterior capsular opacification in 118 eyes (27.4%). The most important prognostic factor for poor outcome was congenital cataract (odds ratio [OR]: 26.3; 95% confidence interval [CI], 4.4-158.5) and total cataract (OR: 4.8; 95% CI, 1.3-17).

Cataract, Visual Impairment and Long-Term Mortality in a Rural Cohort in India: The Andhra Pradesh Eye Disease Study

Background A large-scale prevalence survey of blindness and visual impairment (The Andhra Pradesh Eye Diseases Study [APEDS1]) was conducted between 1996-2000 on 10,293 individuals of all ages in three rural and one urban clusters in Andhra Pradesh, Southern India. More than a decade later (June 2009-March 2010), APEDS1 participants in rural clusters were traced (termed APEDS2) to determine ocular risk factors for mortality in this longitudinal cohort. Methods and Findings Mortality hazard ratio (HR) analysis was performed for those aged >30 years at APEDS1, using Cox proportional hazard regression models to identify associations between ocular exposures and risk of mortality. Blindness and visual impairment (VI) were defined using Indian definitions. 799/4,188 (19.1%) participants had died and 308 (7.3%) had migrated. Mortality was higher in males than females (p<0.001). In multivariable analysis, after adjusting for age, gender, diabetes, hypertension, body mass index, smoking and education status the mortality HR was 1.9 (95% CI: 1.5-2.5) for blindness; 1.4 (95% CI: 1.2-1.7) for VI; 1.8 (95% CI: 1.4-2.3) for pure nuclear cataract, 1.5 (95% CI: 1.1-2.1) for pure cortical cataract; 1.96 (95% CI: 1.6-2.4) for mixed cataract, 2.0 (95% CI: 1.4-2.9) for history of cataract surgery, and 1.58 (95% CI: 1.3-1.9) for any cataract. When all these factors were included in the model, the HRs were attenuated, being 1.5 (95% CI: 1.1-2.0) for blindness and 1.2 (95% CI: 0.9-1.5) for VI. For lens type, the HRs were as follows: pure nuclear cataract, 1.6 (95% CI: 1.3-2.1); pure cortical cataract, 1.5 (95% CI: 1.1-2.1); mixed cataract, 1.8 (95% CI: 1.4-2.2), and history of previous cataract surgery, 1.8 (95% CI: 1.3-2.6). Conclusions All types of cataract, history of cataract surgery and VI had an increased risk of mortality that further suggests that these could be potential markers of ageing.

Is microsporidial keratitis a seasonal infection in India

Microsporidia are emerging ocular pathogens. In this study, we describe the seasonal trends of microsporidial keratitis. The incidence of microsporidial keratitis is increasing in India, with a seasonal trend towards disease onset during the monsoon.

Associated factors for age-related maculopathy in the adult population in southern India: the Andhra Pradesh Eye Disease Study

Background: To assess prevalence, potential risk factors and population attributable risk percentage (PAR) for age-related maculopathy (ARM) in the Indian state of Andhra Pradesh. Methods: A population-based study, cross-sectional epidemiological study was conducted in the state of Andhra Pradesh in India during 1996 and 2000. Participants from 94 clusters in one urban and three rural areas representative of the population of Andhra Pradesh underwent a detailed interview and a detailed dilated ocular evaluation by trained professionals. This report presents the prevalence estimates of ARM and examines the association of ARM with potential risk factors in persons aged 40–102 years (n = 3723). ARM was defined as per the international classification and grading system. Results: ARM was present in 327 subjects, an age–gender–area-adjusted prevalence of 8.9% (95% confidence interval (CI), 8.1% to 9.9%). Multivariate analysis showed that, the adjusted prevalence of ARM was significantly higher in those 70 years of age or older (adjusted odds ratio (OR), 3.65; 95% CI 2.24 to 5.94) and in subjects with hypertension OR 1.30 (95% CI 1.02 to 1.65). The presence of any cataract and urban residence were significantly associated with increased prevalence of ARM (OR 1.67; 95% CI 1.27 to 2.21 and 2.30; 95% CI 1.79 to 2.96) respectively. Increased intraocular pressure (IOP) and increased cup-to-disc ratio (CDR) were also significantly associated with increased prevalence of ARM (OR 1.03; 95% CI 1.002 to 1.06 and 2.25; 95% CI 1.10 to 4.67) respectively. The PAR for hypertension and any cataract was 12% and 18% respectively in this population. Conclusion: The prevalence of ARM in this south Indian population is similar to those reported from other developed countries. Increased age, increased IOP and increased CDR were significantly associated with the increased risk of ARM.