Aravind Eye Hospital

Importance: Deep learning is a family of computational methods that allow an algorithm to program itself by learning from a large set of examples that demonstrate the desired behavior, removing the need to specify rules explicitly. Application of these methods to medical imaging requires further assessment and validation. Objective: To apply deep learning to create an algorithm for automated detection of diabetic retinopathy and diabetic macular edema in retinal fundus photographs. Design and Setting: A specific type of neural network optimized for image classification called a deep convolutional neural network was trained using a retrospective development data set of 128 175 retinal images, which were graded 3 to 7 times for diabetic retinopathy, diabetic macular edema, and image gradability by a panel of 54 US licensed ophthalmologists and ophthalmology senior residents between May and December 2015. The resultant algorithm was validated in January and February 2016 using 2 separate data sets, both graded by at least 7 US board-certified ophthalmologists with high intragrader consistency. Exposure: Deep learning-trained algorithm. Main Outcomes and Measures: The sensitivity and specificity of the algorithm for detecting referable diabetic retinopathy (RDR), defined as moderate and worse diabetic retinopathy, referable diabetic macular edema, or both, were generated based on the reference standard of the majority decision of the ophthalmologist panel. The algorithm was evaluated at 2 operating points selected from the development set, one selected for high specificity and another for high sensitivity. Results: The EyePACS-1 data set consisted of 9963 images from 4997 patients (mean age, 54.4 years; 62.2% women; prevalence of RDR, 683/8878 fully gradable images [7.8%]); the Messidor-2 data set had 1748 images from 874 patients (mean age, 57.6 years; 42.6% women; prevalence of RDR, 254/1745 fully gradable images [14.6%]). For detecting RDR, the algorithm had an area under the receiver operating curve of 0.991 (95% CI, 0.988-0.993) for EyePACS-1 and 0.990 (95% CI, 0.986-0.995) for Messidor-2. Using the first operating cut point with high specificity, for EyePACS-1, the sensitivity was 90.3% (95% CI, 87.5%-92.7%) and the specificity was 98.1% (95% CI, 97.8%-98.5%). For Messidor-2, the sensitivity was 87.0% (95% CI, 81.1%-91.0%) and the specificity was 98.5% (95% CI, 97.7%-99.1%). Using a second operating point with high sensitivity in the development set, for EyePACS-1 the sensitivity was 97.5% and specificity was 93.4% and for Messidor-2 the sensitivity was 96.1% and specificity was 93.9%. Conclusions and Relevance: In this evaluation of retinal fundus photographs from adults with diabetes, an algorithm based on deep machine learning had high sensitivity and specificity for detecting referable diabetic retinopathy. Further research is necessary to determine the feasibility of applying this algorithm in the clinical setting and to determine whether use of the algorithm could lead to improved care and outcomes compared with current ophthalmologic assessment.

There is extensive evidence showing that improving eye health contributes directly and indirectly to achieving many Sustainable Development Goals, including reducing poverty and improving work productivity, general and mental health, and education and equity. Improving eye health is a practical and cost-effective way of unlocking human potential. Eye health needs to be reframed as an enabling, cross-cutting issue within the sustainable development framework.

AIMS/BACKGROUND: To determine the epidemiological characteristics and risk factors predisposing to corneal ulceration in Madurai, south India, and to identify the specific pathogenic organisms responsible for infection. METHODS: All patients with suspected infectious central corneal ulceration presenting to the ocular microbiology and cornea service at Aravind Eye Hospital, Madurai, from 1 January to 31 March 1994 were evaluated. Sociodemographic data and information pertaining to risk factors were recorded, all patients were examined, and corneal cultures and scrapings were performed. RESULTS: In the 3 month period 434 patients with central corneal ulceration were evaluated. A history of previous corneal injury was present in 284 patients (65.4%). Cornea cultures were positive in 297 patients (68.4%). Of those individuals with positive cultures 140 (47.1%) had pure bacterial infections, 139 (46.8%) had pure fungal infections, 15 (5.1%) had mixed bacteria and fungi, and three (1.0%) grew pure cultures of Acanthamoeba. The most common bacterial pathogen isolated was Streptococcus pneumoniae, representing 44.3% of all positive bacterial cultures, followed by Pseudomonas spp (14.4%). The most common fungal pathogen isolated was Fusarium spp, representing 47.1% of all positive fungal cultures, followed by Aspergillus spp (16.1%). CONCLUSIONS: Central corneal ulceration is a common problem in south India and most often occurs after a superficial corneal injury with organic material. Bacterial and fungal infections occur in equal numbers with Streptococcus pneumoniae accounting for the majority of bacterial ulcers and Fusarium spp responsible for most of the fungal infections. These findings have important public health implications for the treatment and prevention of corneal ulceration in the developing world.

Optic nerve head (ONH) segmentation problem has been of interest for automated glaucoma assessment. Although various segmentation methods have been proposed in the recent past, it is difficult to evaluate and compare the performance of individual methods due to a lack of a benchmark dataset. The problem of segmentation involves segmentation of optic disk and cup region within ONH region. Available datasets do not incorporate challenges present in this problem. In this data paper, we present a comprehensive dataset of retinal images which include both normal and glaucomatous eyes and manual segmentations from multiple human experts. Both area and boundary-based evaluation measures are presented to evaluate a method on various aspects relevant to the problem of glaucoma assessment.

BACKGROUND: Clinical vitamin A deficiency affects millions of children worldwide, and subclinical deficiency is even more common. Supplemental vitamin A has been reported to reduce mortality among these children, but the results have been questioned. METHODS: We conducted a randomized, controlled, masked clinical trial for one year in southern India involving 15,419 preschool-age children who received either 8.7 mumol (8333 IU) of vitamin A and 46 mumol (20 mg) of vitamin E (the treated group) or vitamin E alone (the control group). Vitamin supplements were delivered weekly by community health volunteers who also recorded mortality and morbidity. Weekly contact was made with at least 88 percent of the children in both study groups. The base-line characteristics of the children were similar and documented a high prevalence of vitamin A deficiency and undernutrition. RESULTS: One hundred twenty-five deaths occurred, of which 117 were not accidental. The risk of death in the group treated with vitamin A was less than half that in the control group (relative risk, 0.46; 95 percent confidence interval, 0.30 to 0.71). The risk was most reduced among children under 3 years of age (6 to 11 months--relative risk, 0.28; 95 percent confidence interval, 0.09 to 0.85; 12 to 35 months--relative risk, 0.46; 95 percent confidence interval, 0.26 to 0.81) and among those who were chronically undernourished, as manifested by stunting (relative risk, 0.11; 95 percent confidence interval, 0.03 to 0.36). The symptom-specific risk of mortality was significantly associated with diarrhea, convulsions, and other infection-related symptoms. CONCLUSIONS: The regular provision of a supplement of vitamin A to children, at a level potentially obtainable from foods, in an area where vitamin A deficiency and under-nutrition are documented public health problems contributed substantially to children's survival; mortality was reduced on average by 54 percent.

Purpose: COVID-19-associated rhino-orbital-cerebral mucormycosis (ROCM) has reached epidemic proportion during India's second wave of COVID-19 pandemic, with several risk factors being implicated in its pathogenesis. This study aimed to determine the patient demographics, risk factors including comorbidities, and medications used to treat COVID-19, presenting symptoms and signs, and the outcome of management. Methods: This was a retrospective, observational study of patients with COVID-19-associated ROCM managed or co-managed by ophthalmologists in India from January 1, 2020 to May 26, 2021. Results: Of the 2826 patients, the states of Gujarat (22%) and Maharashtra (21%) reported the highest number of ROCM. The mean age of patients was 51.9 years with a male preponderance (71%). While 57% of the patients needed oxygen support for COVID-19 infection, 87% of the patients were treated with corticosteroids, (21% for > 10 days). Diabetes mellitus (DM) was present in 78% of all patients. Most of the cases showed onset of symptoms of ROCM between day 10 and day 15 from the diagnosis of COVID-19, 56% developed within 14 days after COVID-19 diagnosis, while 44% had delayed onset beyond 14 days. Orbit was involved in 72% of patients, with stage 3c forming the bulk (27%). Overall treatment included intravenous amphotericin B in 73%, functional endoscopic sinus surgery (FESS)/paranasal sinus (PNS) debridement in 56%, orbital exenteration in 15%, and both FESS/PNS debridement and orbital exenteration in 17%. Intraorbital injection of amphotericin B was administered in 22%. At final follow-up, mortality was 14%. Disease stage >3b had poorer prognosis. Paranasal sinus debridement and orbital exenteration reduced the mortality rate from 52% to 39% in patients with stage 4 disease with intracranial extension (p < 0.05). Conclusion: : Corticosteroids and DM are the most important predisposing factors in the development of COVID-19-associated ROCM. COVID-19 patients must be followed up beyond recovery. Awareness of red flag symptoms and signs, high index of clinical suspicion, prompt diagnosis, and early initiation of treatment with amphotericin B, aggressive surgical debridement of the PNS, and orbital exenteration, where indicated, are essential for successful outcome.

Automatic retinal image analysis is emerging as an important screening tool for early detection of eye diseases. Glaucoma is one of the most common causes of blindness. The manual examination of optic disk (OD) is a standard procedure used for detecting glaucoma. In this paper, we present an automatic OD parameterization technique based on segmented OD and cup regions obtained from monocular retinal images. A novel OD segmentation method is proposed which integrates the local image information around each point of interest in multidimensional feature space to provide robustness against variations found in and around the OD region. We also propose a novel cup segmentation method which is based on anatomical evidence such as vessel bends at the cup boundary, considered relevant by glaucoma experts. Bends in a vessel are robustly detected using a region of support concept, which automatically selects the right scale for analysis. A multi-stage strategy is employed to derive a reliable subset of vessel bends called r-bends followed by a local spline fitting to derive the desired cup boundary. The method has been evaluated on 138 images comprising 33 normal and 105 glaucomatous images against three glaucoma experts. The obtained segmentation results show consistency in handling various geometric and photometric variations found across the dataset. The estimation error of the method for vertical cup-to-disk diameter ratio is 0.09/0.08 (mean/standard deviation) while for cup-to-disk area ratio it is 0.12/0.10. Overall, the obtained qualitative and quantitative results show effectiveness in both segmentation and subsequent OD parameterization for glaucoma assessment.

Uveitis, a complex intraocular inflammatory disease results from several etiological entities. Causes of uveitis are known to vary in different populations depending upon the ecological, racial and socioeconomic variations of the population studied. Tropical countries are unique in their climate, prevailing pathogens and in the existing diseases, which further influence the epidemiological and geographical distribution of specific entities. We provide an overview of the pattern of uveitis of 15221 cases in 24 case series reported from several countries over 35 years (1972-2007) and we integrate it with our experience of an additional 8759 cases seen over six years (1996-2001) at a large community-based eye hospital. Uveitis accounted for 0.8% of our hospital-based outpatient visits. The uveitis was idiopathic in 44.6%, the most commonly identified entities in the cohort included leptospiral uveitis (9.7%), tuberculous uveitis (5.6%) and herpetic uveitis (4.9%). The most common uveitis in children below 16 years (616 patients; 7.0% of the total cohort) was pediatric parasitic anterior uveitis, (182 children, 29.5% of the pediatric cohort), whereas the most common uveitis in patients above 60 years (642 patients; 7.3% of the total cohort) was herpetic anterior uveitis, (78 patients, 12.1% of the elderly cohort). Etiologies varied with the age group of the patients. As in other tropical countries, a high prevalence of infectious uveitis was seen in this population.

OBJECTIVE: To compare topical natamycin vs voriconazole in the treatment of filamentous fungal keratitis. METHODS: This phase 3, double-masked, multicenter trial was designed to randomize 368 patients to voriconazole (1%) or natamycin (5%), applied topically every hour while awake until reepithelialization, then 4 times daily for at least 3 weeks. Eligibility included smear-positive filamentous fungal ulcer and visual acuity of 20/40 to 20/400. MAIN OUTCOME MEASURES: The primary outcome was best spectacle-corrected visual acuity at 3 months; secondary outcomes included corneal perforation and/or therapeutic penetrating keratoplasty. RESULTS: A total of 940 patients were screened and 323 were enrolled. Causative organisms included Fusarium (128 patients [40%]), Aspergillus (54 patients [17%]), and other filamentous fungi (141 patients [43%]). Natamycintreated cases had significantly better 3-month best spectacle-corrected visual acuity than voriconazole-treated cases (regression coefficient=0.18 logMAR; 95% CI, 0.30 to 0.05; P=.006). Natamycin-treated cases were less likely to have perforation or require therapeutic penetrating keratoplasty (odds ratio=0.42; 95% CI, 0.22 to 0.80; P=.009). Fusarium cases fared better with natamycin than with voriconazole (regression coefficient=0.41 logMAR; 95% CI,0.61 to 0.20; P<.001; odds ratio for perforation=0.06; 95% CI, 0.01 to 0.28; P<.001), while non-Fusarium cases fared similarly (regression coefficient=0.02 logMAR; 95% CI, 0.17 to 0.13; P=.81; odds ratio for perforation=1.08; 95% CI, 0.48 to 2.43; P=.86). CONCLUSIONS: Natamycin treatment was associated with significantly better clinical and microbiological outcomes than voriconazole treatment for smear-positive filamentous fungal keratitis, with much of the difference attributable to improved results in Fusarium cases. APPLICATION TO CLINICAL PRACTICE: Voriconazole should not be used as monotherapy in filamentous keratitis. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00996736

PURPOSE: To determine the influence of risk factors, climate, and geographical variation on the microbial keratitis in South India. METHODS: A retrospective analysis of all clinically diagnosed infective keratitis presenting between September 1999 and August 2002 was performed. A standardised form was filled out for each patient, documenting sociodemographic features and information pertaining to risk factors. Corneal scrapes were collected and subjected to culture and microscopy. RESULTS: A total of 3,183 consecutive patients with infective keratitis were evaluated, of which 1,043 (32.77%) were found to be of bacterial aetiology, 1,095 (34.4%) were fungal, 33 (1.04%) were Acanthamoeba, 76 (2.39%) were both fungal and bacterial, and the remaining 936 (29.41%) were found to be culture negative. The predominant bacterial and fungal pathogens isolated were Streptococcus pneumoniae (35.95%) and Fusarium spp. (41.92%), respectively. Most of the patients (66.84%) with fungal keratitis were between 21 and 50 years old, and 60.21% of the patients with bacterial keratitis were older than 50 (p < 0.0001) (95% CI: 5.19-7.19). A majority of patients (64.75%) with fungal keratitis were agricultural workers (p < 0.0001) [odds ratio (OR): 1.4; 95% CI: 1.19-1.61], whereas bacterial keratitis occurred more commonly (57.62%) in nonagricultural workers (p < 0.0001) (OR: 2.88; 95% CI: 2.47-3.36). Corneal injury was identified in 2,256 (70.88%) patients, and it accounted for 92.15% in fungal keratitis (p < 0.0001) (OR: 7.7; 95% CI: 6.12-9.85) and 100% in Acanthamoeba keratitis. Injuries due to vegetative matter (61.28%) were identified as a significant cause for fungal keratitis (p < 0.0001) (OR: 23.6; 95% CI: 19.07-29.3) and due to mud (84.85%) for Acanthamoeba keratitis (p < 0.0001) (OR: 26.01; 95% CI: 3.3-6.7). Coexisting ocular diseases predisposing to bacterial keratitis accounted for 68.17% (p < 0.0001) (OR: 33.99; 95% CI: 27.37-42.21). The incidence of fungal keratitis was higher between June and September, and bacterial keratitis was less during this period. CONCLUSION: The risk of agricultural predominance and vegetative corneal injury in fungal keratitis and associated ocular diseases in bacterial keratitis increase susceptibility to corneal infection. A hot, windy climate makes fungal keratitis more frequent in tropical zones, whereas bacterial keratitis is independent of seasonal variation and frequent in temperate zones. Microbial pathogens show geographical variation in their prevalence. Thus, the spectrum of microbial keratitis varies with geographical location influenced by the local climate and occupational risk factors.

Anyone who has spent time in Asia or Africa can invariably recall a vivid image of a blind beggar, sometimes an elderly person but frequently a child with opaque corneas, haunting the bazaars and marketplaces of cities and villages. The spectre is so common that it almost passes unnoticed, but these individuals who are bilaterally blind represent only a small fraction of the millions who suffer monocular blindness as a result of corneal trauma and subsequent microbial keratitis. With the global figure of blindness rapidly approaching 40 million, attention naturally is focused on cataract, which is responsible for 50% or more of all visual disability, and trachoma which is still an enormous public health problem affecting 500 million people worldwide and responsible for 25% of all bilaterally blind individuals.1 Xerophthalmia, onchocerciasis, and glaucoma account for several millions more of the 85% of the world’s blind individuals who live in developing countries in Asia and Africa.2 While corneal blindness in the developing world has traditionally been attributed to trachoma, xerophthalmia, …

IMPORTANCE: More than 60 million people in India have diabetes and are at risk for diabetic retinopathy (DR), a vision-threatening disease. Automated interpretation of retinal fundus photographs can help support and scale a robust screening program to detect DR. OBJECTIVE: To prospectively validate the performance of an automated DR system across 2 sites in India. DESIGN, SETTING, AND PARTICIPANTS: This prospective observational study was conducted at 2 eye care centers in India (Aravind Eye Hospital and Sankara Nethralaya) and included 3049 patients with diabetes. Data collection and patient enrollment took place between April 2016 and July 2016 at Aravind and May 2016 and April 2017 at Sankara Nethralaya. The model was trained and fixed in March 2016. INTERVENTIONS: Automated DR grading system compared with manual grading by 1 trained grader and 1 retina specialist from each site. Adjudication by a panel of 3 retinal specialists served as the reference standard in the cases of disagreement. MAIN OUTCOMES AND MEASURES: Sensitivity and specificity for moderate or worse DR or referable diabetic macula edema. RESULTS: Of 3049 patients, 1091 (35.8%) were women and the mean (SD) age for patients at Aravind and Sankara Nethralaya was 56.6 (9.0) years and 56.0 (10.0) years, respectively. For moderate or worse DR, the sensitivity and specificity for manual grading by individual nonadjudicator graders ranged from 73.4% to 89.8% and from 83.5% to 98.7%, respectively. The automated DR system's performance was equal to or exceeded manual grading, with an 88.9% sensitivity (95% CI, 85.8-91.5), 92.2% specificity (95% CI, 90.3-93.8), and an area under the curve of 0.963 on the data set from Aravind Eye Hospital and 92.1% sensitivity (95% CI, 90.1-93.8), 95.2% specificity (95% CI, 94.2-96.1), and an area under the curve of 0.980 on the data set from Sankara Nethralaya. CONCLUSIONS AND RELEVANCE: This study shows that the automated DR system generalizes to this population of Indian patients in a prospective setting and demonstrates the feasibility of using an automated DR grading system to expand screening programs.

PURPOSE OF REVIEW: Throughout the world, fungal keratitis is a leading cause of ocular morbidity. The purpose of this review is to discuss the recently published literature in relation to the epidemiology, etiology, diagnosis, and therapy of fungal keratitis. RECENT FINDINGS: Globally, the incidence of keratomycoses and systemic mycoses is rising. Current therapies are often ineffective. Ongoing research toward rapid diagnosis and specific drug therapy could minimize the morbidity caused by this preventable disease. New antifungal drugs, including voriconazole, have been applied recently for the treatment of keratomycosis. SUMMARY: The incidence of fungal keratitis is on the rise in the densely populated continents of Asia and Africa. Filamentous fungi are the most frequently reported pathogens. Polyene antifungal antibiotics, the first-line therapy in fungal keratitis, are not effective in severe keratomycosis. Imidazole derivatives such as voriconazole and echinocandin may be the better choice in the future.

PURPOSE: To study the epidemiological characteristics and laboratory diagnosis of fungal keratitis seen at a tertiary eye care referral centre in South India. METHODS: A retrospective review of all culture-proven fungal keratitis seen over a 3-year period, September 1999 through August 2002. RESULTS: Fungal aetiology were confirmed in 1095 (34.4%) of 3183 corneal ulcers. The predominant fungal species isolated was Fusarium spp (471; 42.82%) followed by Aspergillus spp (286; 26%). Males (712; 65.08%) were more often affected (P<0.0001). A large proportion of the patients (732; 66.85%) were in the younger age group (21 to 50 years). A majority (879; 80.27%) came from rural areas (P<0.0001), and most patients (709; 64.75%) were farmers (P<0.0001). Ocular trauma (1009; 92.15%) was a highly significant risk factor (P<0.0001) and vegetative injuries (671; 61.28%) were identified as a significant cause for fungal keratitis (P<0.0001). 172 (15.71%) patients had concurrent diabetes mellitus. The sensitivity of 10% potassium hydroxide (KOH) wet mount preparation was higher (99.23%) than Gram-stained smear (88.73%) (P<0.0001). Incidence of fungal keratitis was higher between June and September. CONCLUSION: Agricultural activity and related ocular trauma were principal causes of mycotic keratitis. A potassium hydroxide (KOH) wet mount preparation is a simple, and sensitive, method for diagnosis

OBJECTIVE: This study was designed to propose a classification scheme for platforms of surgical delivery in low- and middle-income countries (LMICs) and to review the literature documenting their effectiveness, cost-effectiveness, sustainability, and role in training. Approximately 28 % of the global burden of disease is surgical. In LMICs, much of this burden is borne by a rapidly growing international charitable sector, in fragmented platforms ranging from short-term trips to specialized hospitals. Systematic reviews of these platforms, across regions and across disease conditions, have not been performed. METHODS: A systematic review of MEDLINE and EMBASE databases was performed from 1960 to 2013. Inclusion and exclusion criteria were defined a priori. Bibliographies of retrieved studies were searched by hand. Of the 8,854 publications retrieved, 104 were included. RESULTS: Surgery by international charitable organizations is delivered under two, specialized hospitals and temporary platforms. Among the latter, short-term surgical missions were the most common and appeared beneficial when no other option was available. Compared to other platforms, however, worse results and a lack of cost-effectiveness curtailed their role. Self-contained temporary platforms that did not rely on local infrastructure showed promise, based on very few studies. Specialized hospitals provided effective treatment and appeared sustainable; cost-effectiveness evidence was limited. CONCLUSIONS: Because the charitable sector delivers surgery in vastly divergent ways, systematic review of these platforms has been difficult. This paper provides a framework from which to study these platforms for surgery in LMICs. Given the available evidence, self-contained temporary platforms and specialized surgical centers appear to provide more effective and cost-effective care than short-term surgical mission trips, except when no other delivery platform exists.

Digital eye strain (DES) is an entity encompassing visual and ocular symptoms arising due to the prolonged use of digital electronic devices. It is characterized by dry eyes, itching, foreign body sensation, watering, blurring of vision, and headache. Non-ocular symptoms associated with eye strain include stiff neck, general fatigue, headache, and backache. A variable prevalence ranging from 5 to 65% has been reported in the pre-COVID-19 era. With lockdown restrictions during the pandemic, outdoor activities were restricted for all age groups, and digital learning became the norm for almost 2 years. While the DES prevalence amongst children alone rose to 50–60%, the symptoms expanded to include recent onset esotropia and vergence abnormalities as part of the DES spectrum. New-onset myopia and increased progression of existing myopia became one of the most significant ocular health complications. Management options for DES include following correct ergonomics like reducing average daily screen time, frequent blinking, improving lighting, minimizing glare, taking regular breaks from the screen, changing focus to distance object intermittently, and following the 20-20-20 rule to reduce eye strain. Innovations in this field include high-resolution screens, inbuilt antireflective coating, matte-finished glass, edge-to-edge displays, and image smoothening graphic effects. Further explorations should focus on recommendations for digital screen optimization, novel spectacle lens technologies, and inbuilt filters to optimize visual comfort. A paradigm shift is required in our understanding of looking at DES from an etiological perspective, so that customized solutions can be explored accordingly. The aim of this review article is to understand the pathophysiology of varied manifestations, predisposing risk factors, varied management options, along with changing patterns of DES prevalence post COVID-19.

OBJECTIVE: To assess the impact of supplementing newborn infants with vitamin A on mortality at age 6 months. DESIGN: Community based, randomised, double blind, placebo controlled trial. SETTING: Two rural districts of Tamil Nadu, southern India. PARTICIPANTS: 11 619 newborn infants allocated 24 000 IU oral vitamin A or placebo on days 1 and 2 after delivery. MAIN OUTCOME MEASURE: Primary outcome measure was mortality at age 6 months. RESULTS: Infants in the vitamin A group had a 22% reduction in total mortality (95% confidence interval 4% to 37%) compared with those in the placebo group. Vitamin A had an impact on mortality between two weeks and three months after treatment, with no additional impact after three months. CONCLUSION: Supplementing newborn infants with vitamin A can significantly reduce early infant mortality.

Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the retina occurring principally in new born preterm infants. It is an avoidable cause of childhood blindness. With the increase in the survival of preterm babies, ROP has become the leading cause of preventable childhood blindness throughout the world. A simple screening test done within a few weeks after birth by an ophthalmologist can avoid this preventable blindness. Although screening guidelines and protocols are strictly followed in the developed nations, it lacks in developing economies like India and China, which have the highest number of preterm deliveries in the world. The burden of this blindness in these countries is set to increase tremendously in the future, if corrective steps are not taken immediately. ROP first emerged in 1940s and 1950s, when it was called retrolental fibroplasia. Several epidemics of this disease were and are still occurring in different regions of the world and since then a lot of research has been done on this disease. However, till date very few comprehensive review articles covering all the aspects of ROP are published. This review highlights the past, present and future strategies in managing this disease. It would help the pediatricians to update their current knowledge on ROP.

OBJECTIVE: To determine whether there is a benefit in clinical outcomes with the use of topical corticosteroids as adjunctive therapy in the treatment of bacterial corneal ulcers. METHODS: Randomized, placebo-controlled, double-masked, multicenter clinical trial comparing prednisolone sodium phosphate, 1.0%, to placebo as adjunctive therapy for the treatment of bacterial corneal ulcers. Eligible patients had a culture-positive bacterial corneal ulcer and received topical moxifloxacin for at least 48 hours before randomization. MAIN OUTCOME MEASURES: The primary outcome was best spectacle-corrected visual acuity (BSCVA) at 3 months from enrollment. Secondary outcomes included infiltrate/scar size, reepithelialization, and corneal perforation. RESULTS: Between September 1, 2006, and February 22, 2010, 1769 patients were screened for the trial and 500 patients were enrolled. No significant difference was observed in the 3-month BSCVA (-0.009 logarithm of the minimum angle of resolution [logMAR]; 95% CI, -0.085 to 0.068; P = .82), infiltrate/scar size (P = .40), time to reepithelialization (P = .44), or corneal perforation (P > .99). A significant effect of corticosteroids was observed in subgroups of baseline BSCVA (P = .03) and ulcer location (P = .04). At 3 months, patients with vision of counting fingers or worse at baseline had 0.17 logMAR better visual acuity with corticosteroids (95% CI, -0.31 to -0.02; P = .03) compared with placebo, and patients with ulcers that were completely central at baseline had 0.20 logMAR better visual acuity with corticosteroids (-0.37 to -0.04; P = .02). CONCLUSIONS: We found no overall difference in 3-month BSCVA and no safety concerns with adjunctive corticosteroid therapy for bacterial corneal ulcers. APPLICATION TO CLINICAL PRACTICE: Adjunctive topical corticosteroid use does not improve 3-month vision in patients with bacterial corneal ulcers. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00324168.

AIMS: To assess the prevalence of vision impairment, blindness, and cataract surgery and to evaluate visual acuity outcomes after cataract surgery in a south Indian population. METHODS: Cluster sampling was used to randomly select a cross sectional sample of people > or =50 years of age living in the Tirunelveli district of south India. Eligible subjects in 28 clusters were enumerated through a door to door household survey. Visual acuity measurements and ocular examinations were performed at a selected site within each of the clusters in early 2000. The principal cause of visual impairment was identified for eyes with presenting visual acuity <6/18. Independent replicate testing for quality assurance monitoring was performed in subjects with reduced vision and in a sample of those with normal vision for six of the study clusters. RESULTS: A total of 5795 people in 3986 households were enumerated and 5411 (93.37%) were examined. The prevalence of presenting and best corrected visual acuity > or =6/18 in both eyes was 59.4% and 75.7%, respectively. Presenting vision <6/60 in both eyes (the definition of blindness in India) was found in 11.0%, and in 4.6% with best correction. Presenting blindness was associated with older age, female sex, and illiteracy. Cataract was the principal cause of blindness in at least one eye in 70.6% of blind people. The prevalence of cataract surgery was 11.8%-with an estimated 56.5% of the cataract blind already operated on. Surgical coverage was inversely associated with illiteracy and with female sex in rural areas. Within the cataract operated sample, 31.7% had presenting visual acuity > or =6/18 in both eyes and 11.8% were <6/60; 40% were bilaterally operated on, with 63% pseudophakic. Presenting vision was <6/60 in 40.7% of aphakic eyes and in 5.1% of pseudophakic eyes; with best correction the percentages were 17.6% and 3.7%, respectively. Refractive error, including uncorrected aphakia, was the main cause of visual impairment in cataract operated eyes. Vision <6/18 was associated with cataract surgery in government, as opposed to that in non-governmental/private facilities. Age, sex, literacy, and area of residence were not predictors of visual outcomes. CONCLUSION: Treatable blindness, particularly that associated with cataract and refractive error, remains a significant problem among older adults in south Indian populations, especially in females, the illiterate, and those living in rural areas. Further study is needed to better understand why a significant proportion of the cataract blind are not taking advantage of free of charge eye care services offered by the Aravind Eye Hospital and others in the district. While continuing to increase cataract surgical volume to reduce blindness, emphasis must also be placed on improving postoperative visual acuity outcomes.