Cause Of Vision Research Articles

Vision loss associated with silicone oil endotamponade in vitreoretinal surgery - a review.

To clarify the definition, prevalence and classification of different types of unexplained vision loss associated with silicone oil (SO) endotamponades (SO in situ (SOIS) or after removal of SO (ROSO)) in vitreoretinal surgery and identifying the most specific clinical findings and suggesting possible causes. Review of the literature regarding randomized clinical trials (RCTs), retrospective case-control, cohort studies and case series evaluating the risk of using SO, published in English between 1994 and 2023, conducting a computer-based search of the following databases: PubMed, Web of Science, Scopus and Embase. The search was supplemented using the Medline option 'Related Articles' and consulting review articles on the topic. Findings from reported clinical examinations in SOIS and ROSO are analyzed and finally different theories regarding the underlying pathophysiology are described. From the clinical point of view, findings have been found in OCT, OCTA, microperimetry and electrophysiological studies. Other clearly identifiable causes of vision loss related to the use of SO are listed and commented as differential diagnosis. Finally, the different physiopathological theories of the two types of causes of unexplained vision have been analyzed. Unexpected vision loss under or after SO tamponade (SOIS and ROSO) is a significant concern which is probably underestimated because it is not a clearly defined and known entity. The most frequently described changes were in the ganglion cell complex but this unexpected vision loss remains a serious and unexplained concern for vitreoretinal surgeons and should be identified by clinicians, addressed by manufacturers and reported to Health Authorities as a serious incident according to the new regulation.

Myopia, what causes it and can it be avoided?

Myopia (short‐sightedness or near‐sightedness) is a condition of refraction where vision to distant is impaired. Axial elongation of the eye is the main anatomical cause of myopia.The prevalence of myopia has increased alarmingly fast globally. The estimation of WHO report was that in 2020 27% of world's population would be myopic, and if there will be no changes in the trend then by 2050 there would be 2.56 billion myopic people worldwide. Highest prevalence of myopia has been reported in many South and East Asian countries, where about 80% of the school leavers are myopic. Parental myopia increases the risks of myopia in their children, two myopic parents more than one. Genetic studies have been able to explain only small part of myopia, nor have been able to explain the differences in the prevalence between populations. Myopia relates to higher education, near work and higher occupational status and is mare rare in urban environment and in occupations where people work outdoors. In children myopia usually develop after they had begun attending school and is associated with more time spent on reading and near work and less time on outdoor activities.The major public health concerns connected with myopia are related to its complications. Myopia has become one of the main causes of vision loss due to complications, such as retinal detachment, macular degeneration and haemorrhage, choroidal neovascularization, and open angle glaucoma. The higher myopia is the higher is the risk of these complications. In countries where myopia is common, it is already a significant cause of low vision and blindness.In a Finnish study prevalence of myopia in 7‐ and 11‐year‐olds, was 0.5% and 3.3%, respectively, if daily near work did not exceed 1 h. Multiple regression model adjusted by sex, parental myopia and time spent outdoors, showed that 1 h increase in near work increased the risk of myopia 47% (95% CI 1.099–1.984, P = 0.010) and 35% (CI 1.170–1.548, P < 0.001), in 7‐ and 11‐year‐olds, respectively. Each hour spent outdoors adjusted by sex, parental myopia and time spent outdoors decreased their same risk by 24% (95% CI 0.533–1050, P = 0.096 and 0.648–0.000, P = 0.001, respectively). Higher prevalence of myopia in girls could mainly be explained by their more time spent in near work and less time outdoors.Plenty of long‐term near viewing, and short viewing distance, combined with low amount of time outdoors are risk factors for myopia. Avoiding these factors is more important the younger the child is. It is recommended that the daily time spent outdoors in children should be at least equal to near work time. Early school starting age, increases the risk of myopia and high myopia, and consequently risk for myopia related complications. Great educational stress in young children should be avoided.

Outcome of Therapeutic Penetrating Keratoplasty in R.M. Kedia Eye hospital - A Retrospective Study

Infectious keratitis is the major cause of vision threatening condition and the leading cause of corneal blindness in developing countries. Therapeutic keratoplasty is the procedure for terminating or improving an actively infectious corneal disease. This study was carried out to determine the outcome of therapeutic keratoplasty for infective keratitis at R.M. Kedia eye hospital. This was retrospective study where all cases that underwent TPK for active infective keratitis from May 2019 to April 2020 were included in the study. Data were collected about demographic parameters, indication for surgery, details of donor tissue in terms of donor size, graft size and endothelial density. The outcome of TPK was measured in terms of anatomic stability, eradication of disease, graft clarity and development of cataract and glaucoma. 30 eyes of 30 patients underwent TPK for infective keratitis. 73.3% were male. Average age of the patients was 42. In 60% of patients organisms were isolated as follows: 11 cases of fungus, 3 cases of bacteria and 4 cases of mixed bacteria and fungus. Two surgeries (6.6%) were combined with extracapsular cataract extraction without posterior chamber intraocular lens. The eradication of infection after primary TPK was 23 (76.8%). Twelve eyes (40%) had documentation of variable grades of cataract. One case had secondary glaucoma. Six cases (20%) had graft failure. Therapeutic keratoplasty is the procedure for terminating or improving an actively infectious corneal disease. It helps to save the eye and preserve vision in severe infective keratitis. There is a high incidence of postoperative glaucoma, cataract, and graft failure in such a surgery.

Mucor Mycosis Maiming COVID-19 Recovered Patients in India?

The year 2021 will go in the history of Indian Ophthalmology as the year of fungal infections among Covid 19 recovered patients as a leading cause of vision or eye loss and facial disfigurement due to post -Covid 19 Fungi- mucor mycosis infections. First published article of mucor mycosis (MM) leading to loss of eye and disfigurement of the face was traced to 1970 in USA. First media report in India came from Ganga Ram Hospital in Delhi, that treated 12 cases of COVID triggered deadly Mucor mycosis fungus cases. Eye & ENT surgeon had to do resection and fungus debridement in 10 cases in one fortnight in December 2020 of which half lost one eye permanently. Mucor mycosis (MM) is an aggressive opportunistic fungal infection, affecting any parts of the body, but rhino-cerebral-orbital type is the commonest leading to blindness and facial disfiguration. Doctors at Bowring and Lady Curzon Medical College Hospital, Bengaluru which has treated more than 140 patients with mucor mycosis, after cell culture tests have confirmed in 95% of the cases the presence of Mucor mycosis, and remaining MM, Aspergillus niger and Candida albicans. Since Mid-April 2021 India has reported about 31,000 MM cases as on 12 June 2021. It is fared that nearly 50% of them have lost at least one eye and some both. Five states of Maharashtra, Gujarat, Rajasthan, Karnataka, and Andhra Pradesh contribute nearly two thirds of the cases and deaths. The latest report of 1700 hrs on 13 June 2021, from Maharashtra puts the total cases at 7395, deaths at 720, 2212 cured and 4463 still under treatment. This state has seen threefold increase in the MM cases reported in just 3 weeks’ time between 25th May and 13 June 2021. Among those recovered one has witnessed lot of facial disfigurement, due to the damages to eyes, nose, jaw bones and oral cavity. Some of them who can afford go in for multiple plastic surgeries costing anywhere between INR 2.5 to 15 million. Traditionally mucor mycosis treatment must start without waiting for laboratory confirmation, but recently a new diagnostic tool with the capability for confirming infection in 24-48 hours is being promoted and is likely to help minimise the damage at least among those who can afford. In this review I have collated and presenting epidemiology, Pathophysiology, available diagnostic support, and treatment of MM infections affecting eyes, nose and disfigurement of face and possible reconstructive surgeries from various sources.

Prevalence, Risk Factors, and Causes of Visual Impairment in an Elderly Chinese Uygur Population in Southern Xinjiang.

Purpose To investigate the prevalence, risk factors, and major causes of visual impairment (VI) in an elderly Chinese Uygur population in southern Xinjiang. Methods This was a population-based cross-sectional study. Participants aged 50 years and older from Haohan Country, Xinjiang Uygur Autonomous Region, were enrolled from August 2018 to December 2018 using cluster sampling. Participants underwent examinations including presenting visual acuity (PVA), pinhole vision, slit-lamp, intraocular pressure, and direct ophthalmoscopy. Participants' education and demographic information was collected by a questionnaire. The prevalence, risk factors, and major causes of vision loss were evaluated. Results A total of 1465 participants (85.4% response rate) were enrolled. The mean age of the subjects was 59.1 ± 9.7 years. The prevalence of mild VI, moderate VI, severe VI, and blindness in the better eye was 13.3%, 12.8%, 2.9%, and 3.4%, respectively. The prevalence of low vision and blindness in this study was higher than that in Altay & Tacheng and Changji in northern Xinjiang, lower than that in Luxi, and similar to that in Tibet. The multiple logistic regression analysis showed that age, education level, and body mass index (BMI) were significantly associated with low vision and blindness (P ≤ 0.001, <0.05, 0.002, respectively). The major causes of low vision were cataract (42.6%), refractive error (19.6%), and glaucoma (12.6%), whereas the primary causes of blindness were cataract (34%), glaucoma (34%), and retinitis pigmentosa (10%). Conclusions VI is an important public health issue among elderly Uygur individuals in the area, especially for those with low education levels. Cataract is the leading cause of low vision and blindness.

Combined Vision and Hearing Difficulties Results in Higher Levels of Depression and Chronic Anxiety: Data From a Large Sample of Spanish Adults.

ObjectiveIndividually, vision and hearing impairments have been linked to higher levels of anxiety and depression. We investigated the effect of dual sensory impairment (difficulty seeing and hearing) in a large representative sample of Spanish adults.MethodsData from a total of 23,089 adults (age range: 15–103 years, 45.9% men) from the Spanish National Health Survey 2017 were analyzed. Self-reported difficulty of seeing and hearing (exposures), and depression and chronic anxiety (outcomes) were analyzed. Multivariable logistic regression was assessed for difficulty with vision alone, hearing alone and with difficulty with both, adjusting for gender, age, marital status, living as a couple, education, smoking, alcohol consumption, BMI, physical activity, use of glasses/contact lenses, and hearing aid.ResultsVisual difficulty, hearing difficulty, and dual difficulties were all associated with significantly higher odds for depression (ORs 2.367, 2.098, and 3.852, respectively) and for chronic anxiety (ORs 1.983, 1.942, and 3.385, respectively). Dual sensory difficulty was associated with higher odds ratios for depression and anxiety when compared to either impairment alone.ConclusionDual sensory difficulty is associated with significantly higher odds of anxiety and depression when compared to either vision or hearing difficulty alone. Appropriate interventions are needed to address any reversible causes of vision and hearing as well as anxiety and depression in people in these specific groups.

A retrospective study of causes of visual impairment and use of low vision devices in the low vision clinic in Trinidad and Tobago

PurposeTo determine the causes of visual impairment and the use of low vision devices in patients attending the low vision clinic in Trinidad and Tobago. MethodsA retrospective study of the 222 patients attending the low vision clinic at the University of the West Indies, St Augustine Campus was conducted. The presenting visual acuity, causes of low vision and blindness, and prescribed low vision devices were recorded and analysed to determine the major causes of visual impairment and improvement in visual acuity with low vision aids. ResultsOut of the total 222 participants, 66.66% (n = 148) had low vision while the rest (33.33%, n = 74) were legally blind. Glaucoma was the major cause of low vision (31.08%) and blindness (28.38%) followed by diabetic retinopathy (20.94%, low vision and 20.27%, blindness). A total of 193 low vision devices were prescribed, 79.79% (n = 154) near devices and 20.20% (n = 39) distance devices. The low vision devices were effective in improving both near visual acuity (120 participants reading 1M or 2M) and distance visual acuity (VA better than 3/60). ConclusionThe major causes of vision impairment in Trinidad and Tobago were glaucoma and diabetic retinopathy and low vision devices are effective in improving visual acuity. A comprehensive approach to dealing with the causes of low vision and low vision services are required to mitigate the burden of visual impairment in the country.

P.120 metaplasticity-induced tau phosphorylation is regulated by γ-aminobutyric acid in the hippocampus

A carotid cavernous fistula is a rare type of arteriovenous (AV) fistula due to an abnormal communication between the cavernous sinus and the carotid arterial system. Normal venous return to the cavernous sinus is impeded as high-pressure arterial blood enters the cavernous sinus. The classical triad of symptoms is characterized by pulsating exophthalmos, ocular bruit, and conjunctival chemosis. However, it is important to note that some patients do not exhibit this triad of symptoms.A 49-year-old man presented to the Emergency Department (ED) with a chief complaint of “there is a heartbeat in my eye.” Pertinent history included an episode of trauma 2 months prior to his onset of unilateral vision loss. Computed tomography scan of the head obtained in the ED upon his initial injury was unrevealing. Despite no identifiable pathology, his pain had gradually worsened since ED discharge. On this occasion, an ocular bruit was appreciated over the affected eye, prompting further diagnostic testing. The patient was admitted for urgent cerebral angiography and definitive endovascular neurosurgical intervention to preserve his eyesight. We discuss the clinical presentation, pathophysiology, and diagnostic modalities important to the management of this rare and potentially devastating cause of vision loss.A carotid cavernous fistula is a rare and easily misdiagnosed cause of unilateral ocular pain in the ED. Further, it emphasizes the importance of a detailed clinical history and physical examination to make this diagnosis and save eyesight.

Management of Anisometropic Amblyopia: A Case Report and Brief Review

Background Unilateral functional amblyopia due to anisometropia is a common cause of vision loss in children. There has been a significant amount of research recently to determine the most effective management strategies for such cases, and it is important for clinicians to determine how to apply these findings clinically. Case Report A 6-year-old female presented for her first comprehensive eye exam after failing a school vision screening. She was diagnosed with significant anisometropia with anisometropic amblyopia in her left eye. She was treated with spectacle correction initially, and was eventuallyfit with soft contact lenses to achieve optimal vision and binocularity. Part-time occlusion therapy was also initiated, which was modified throughout the treatment period based on clinical findings. She was also treated with 19 sessions of office-based vision therapy in order to maximize the success of amblyopia treatment. At the completion of the treatment, this patient showed significant improvement in her visual acuity and other non-acuity factors, including contrast sensitivity and binocularity. Conclusions The successful treatment of this patient with anisometropic amblyopia was achieved by the combination of active vision therapy with evidence-based management strategies, consisting of optical correction and occlusion therapy

A ten year study of prevalence, antimicrobial susceptibility pattern, and genotypic characterization of Methicillin resistant Staphylococcus aureus causing ocular infections in a tertiary eye care hospital in South India

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of vision threatening ocular infections. This study aimed to determine the prevalence and antimicrobial susceptibility pattern of MRSA and their genotypic characterization in ocular infections. The study period was from January 2007 to December 2017 in Aravind Eye Hospital, Madurai. Retrospective analysis of clinical records found a total of 1306 Staphylococcus aureus in various ocular infections. Among these, 274 (21%) were found to be MRSA with an increased incidence from 9% in 2007 to 38% in 2017 (P = .007). MRSA was isolated commonly from lacrimal sac infection 89 (32%), lid infection 55 (20%), keratitis 45 (16%) and orbital infection 34 (12%). MRSA isolates showed 100% sensitivity to vancomycin, 91% to chloramphenicol and majority of MRSA isolates were resistant to all fluoroquinolones. MSSA strains showed very minimal resistance to chloramphenicol (5%) and also there was no resistance to vancomycin. In case of the MSSA isolates, resistance to fluroquinolones (ciprofloxacin, gatifloxacin, moxifloxacin, ofloxacin and levofloxacin) was found to increase during study period. Methicillin-resistance is conferred by the carriage of Staphylococcal Cassette Chromosome mec (SCCmec) and most of our isolates were belonged to SCCmec type V and IV which is known to be community acquired MRSA. MLST sequencing on seven housekeeping genes revealed, sequence type ST772 was predominant followed by ST22. Agr typing identified most of the isolates (69) were agr type II (77%). By spa typing, there are 16 spa types were identified, among which 60% of the isolates had t657 spa type.

Prevalence and causes of vision loss in Latin America and the Caribbean in 2015: magnitude, temporal trends and projections

ObjectiveTo estimate the prevalence and causes of blindness and vision impairment for distance and near in Latin America and the Caribbean (LAC) in 2015 and to forecast trends to 2020.MethodsA...

Advances in Retinal Disease Treatment and Diagnosis 2017

Retinal disease is a major cause of poor vision especially in the ageing population, and age related macular degeneration is the main cause of vision loss in the developed world. Early recognition of the signs and symptoms of retinal disease can help prevent ophthalmologic complications and vision loss. It is unsurprising, therefore that retinal imaging and treatment of retinal disease is an active area of research. Founded in 2000, the European Society of Retina Specialists (EURETINA) is Europe’s premier organisation for dissemination of research on retinal disease. In this expert interview, European Ophthalmic Review’s Editor-in-Chief, Maurizio Battaglia Parodi, of the University Vita-Salute, Milan, Italy, discusses the highlights of the 17th EURETINA Congress in Barcelona, Spain on 7–10 September 2017, as well as the year’s other major advances in retinal imaging technology and retinal disease.

Focusing on the signal pathway of diabetic retinopathy and guiding the target therapy of diabetic retinopathy

Diabetic retinopathy (DR) is one of common causes of vision loss.Recent years,progress has been made on the signal pathway in DR which provides more theoretical basis for clinical therapies and more chance for developing targeted therapeutic drugs.Understanding the biological function of the signal pathway in DR is helpful for physicians to selectively control its biological activities,make medical decisions and optimize new approaches to the treatment of DR.How to closely combine the study of signal pathway and targeted therapy in practice is a key link of improving the therapeutic effect of DR.Therefore,we should pay attention to translational medicine and reinforce targeted therapy in DR. Key words: Signal pathway; Diabetes mellitus; Retinopathy; Targeting therapy; Translational medicine

Related factors of postvitrectomy vitreous hemorrhage in proliferative diabetic retinopathy

Background Vitrectomy is an effective method to proliferative diabetic retinopathy (PDR) in type 2 diabetic patients.Postoperative vitreous hemorrhage is a major cause of vision loss.Objective This study was to analyze the related factors of vitreous hemorrhage after vitrectomy in proliferative retinopathy with type 2 diabetes.Methods Three hundred and five eyes of 305 cases who received vitrectomy for PDR from type 2 diabetes were retrospectively investigated.The clinical data of 14 eyes with vitreous hemorrhage after vitrectomy were analyzed.Results Vitreous hemorrhage after vitrectomy occurred in 14 eyes with the incidence 4.6％.The PDR was grade ⅣV in 3 eyes,grade Ⅴ in 4 eyes and grade Ⅵ in 7 eyes.Pars plana vitrectomy with intraocular laser photocoagulation was performed on all the 14 eyes,and 1 eye accepted scleral condensation and 8 eyes accepted silicone oil tamponade.Visual acuity was improved in 6 eyes,unchanged in 4 eyes and worsen in 4 eyes after initial surgery.Vitreous hemorrhage appeared in postoperative 1-7 days in 9 eyes,8 days-3 months in 1 eye,3-6 months in 2 eyes and over 6 months in 2 eyes.The cause for postoperative vitreous hemorrhage included residual neovascular membrane,insufficient photocoagulation range and intensity,neovascularization and instable blood glucose level.Vitreous hemorrhage disappeared in 5 eyes after medicine therapy,and reoperation in 9 eyes.In the end of the follow up,visual acuity improved in 9 eyes,unchanged in 2 eyes and worsen in 3 eyes.Retinas reattached in 13 eyes.However,the retina was still detached in 1 eye with silicone oil tamponade.Conclusions Postoperative vitreous hemorrhage usually occurs within 1 week.The main related factors are residual retinal neovascular membrane,inadequate intraocular laser photocoagulation and unstable blood glucose level.Medicine therapy is effective for postoperative vitreous hemorrhage in type 2 diabetic patients,but re-vitrectomy is needed for excessive vitreous bleeding. Key words: Diabetes mellitus/complication; Proliferative; Retinopathy/treatment, surgery; Vitrectomy; Postoperative vitreous hemorrhage

TBK1Gene Duplication and Normal-Tension Glaucoma

Normal-tension glaucoma (NTG) is a common cause of vision loss. To investigate the role of TANK binding kinase 1 (TBK1) gene duplications in NTG to gain insights into the causes of glaucoma that occurs at low intraocular pressure (IOP). In this multicenter case-control study, we investigated patients who met the criteria for NTG, including glaucomatous optic neuropathy, visual field defects, and maximum recorded untreated IOP of 21 mm Hg or less, and matched controls. Participants (N = 755) were recruited from Southampton, United Kingdom (180 patients and 178 controls), Rochester, Minnesota (65 patients and 12 controls), New York, New York (96 patients and 16 controls), and Iowa City, Iowa (208 controls). Detection of TBK1 gene duplications and comparison of the extent of the identified DNA that is duplicated with prior TBK1 copy number variations associated with NTG. A TBK1 gene duplication was detected in 1 of 96 patients (1.0%) from New York and none of the controls. Analysis of duplication borders with comparative genome hybridization demonstrated that this patient has a novel duplication that has not been previously reported. No gene duplications were detected in any of the other cohorts of patients or controls. Duplication of the TBK1 gene is a rare cause of NTG. The identification of another case of NTG attributed to TBK1 gene duplication strengthens the case that this mutation causes glaucoma.

Prevalence of vision impairment and refractive error in school children in Ba Ria – Vung Tau province, Vietnam

BackgroundTo assess the prevalence of vision impairment and refractive error in school children 12–15 years of age in Ba Ria – Vung Tau province, Vietnam.DesignProspective, cross-sectional study.Participants2238 secondary school children.MethodsSubjects were selected based on stratified multistage cluster sampling of 13 secondary schools from urban, rural and semi-urban areas. The examination included visual acuity measurements, ocular motility evaluation, cycloplegic autorefraction, and examination of the external eye, anterior segment, media and fundus.Main Outcome MeasuresVisual acuity and principal cause of vision impairment.ResultsThe prevalence of uncorrected and presenting visual acuity ≤6/12 in the better eye were 19.4% (95% confidence interval, 12.5–26.3) and 12.2% (95% confidence interval, 8.8–15.6), respectively. Refractive error was the cause of vision impairment in 92.7%, amblyopia in 2.2%, cataract in 0.7%, retinal disorders in 0.4%, other causes in 1.5% and unexplained causes in the remaining 2.6%. The prevalence of vision impairment due to myopia in either eye (–0.50 diopter or greater) was 20.4% (95% confidence interval, 12.8–28.0), hyperopia (≥2.00 D) was 0.4% (95% confidence interval, 0.0–0.7) and emmetropia with astigmatism (≥0.75 D) was 0.7% (95% confidence interval, 0.2–1.2). Vision impairment due to myopia was associated with higher school grade and increased time spent reading and working on a computer.ConclusionsUncorrected refractive error, particularly myopia, among secondary school children in Vietnam is a major public health problem. School-based eye health initiative such as refractive error screening is warranted to reduce vision impairment.

Choroidal hypoperfusion associated with photodynamic therapy for choroidal neovascularization

Choroidal neovascularization (CNV) ithe leading cause of vision disordecaused by variouretinal diseases.Apresent,many therapeutimethodare employed clinically,such aphotodynamitherapy (PDT),anti-vasculaendothelial growth facto(anti-VEGF) and transpupillary thermotherapy (TTT).However,none of them can cure CNV thoroughly and repeated treatmenirequired usually.The reason forecurrenCNV istill unclear.Choroidal hypoperfusion associated with Pdmay be one of the reasons.The purpose of thireview ito discusthe problem of choroidal hypoperfusion associated with PDfoCNV awell aitimpacon the eye and possible solutions.Thipapepresentevidenceof choroidal hypoperfusion aftePDand itrelationship with clinical outcomes.Meanwhile,the effecof combination therapy iassessed.Finally,low-fluence Pdirecommended apotential method to reduce choroidal hypoperfusion. Key words: Photodynamic therapy; Choroidal neovascularization; Choroidal hypoperfusion

Childhood Visual Impairment in Fiji

To establish the prevalence and causes of low vision and blindness in children aged 0 to 15 years in Fiji using existing data and new surveys. Method Childhood visual impairment data on both low visual acuity (<20/60-20/400) and blindness (<20/400) were obtained from existing records at hospital clinics, the school, an outreach service for visually impaired children, primary school screening records, and surveys in high schools and schools for children with multiple disabilities. Crude prevalence was derived and, using 5-year age range and age at onset of vision loss, the probable prevalence per 1000 children was calculated. A total of 81 children were identified; causes were established for 70 children, showing that 69% had unavoidable causes of vision loss (retinal, 39.7% and cortical, 15.5%), with the avoidable cause of low vision and blindness mainly being cataract (15.5%). Probable prevalence was 1.134 per 1000 children (95% confidence interval [CI], 1.115-1.153), with low vision, 0.774 per 1000 children (95% CI, 0.758-0.790) and blindness, 0.36 per 1000 children (95% CI, 0.349-0.371). The rate of severe visual impairment (<20/200) was 0.522 per 1000 children (95% CI, 0.509-0.535), only half of the total vision loss. Both the low to moderate prevalence and mainly unavoidable causes of visual impairment indicated that Fiji, a developing country, has prevalence and causes of visual impairment similar to more resourced, industrialized countries.

Cyclooxygenase-2 and choroidal neovascularization

Choroidal neovascularization(CNV)is one of common causes of vision loss.The pathogenesis and development of CNV are a comprehensive process which is regulated by multiple factors and cytokines.Cyclooxygenase-2(COX-2)is an inducible isoform of cyclooxygenase and rate limiting enzyme in the prostaglandin biosynthesis pathway.COX-2 plays an important role in neovascularization by modulating vascular endothelial growth factor(VEGF),migration and apoptosis of endothelial cell.Recently,some experimental studies demonstrated that COX-2 involves in the information of CNV and the inhibitor of COX-2 can suppress CNV.These results provide a new prospect for the prevention and treatment of the CNV.Biological characteristics of COX-2 and its relationship with CNV are reviewed in this article. Key words: choroidal neovascularization; cyclooxygenase-2; vascular endothelial growth factor

Prevalence and vision-related outcomes of cataract surgery in Gujarat, India

Purpose: Investigate the prevalence and vision-related outcomes of cataract surgery in an area of high cataract surgical rate.Methods: Cluster sampling was used in randomly selecting individuals ≥ 50 years of age in 2007. Participants were queried regarding year and place of previous cataract surgery. Cataract surgical procedures and evidence of surgical complications were recorded. The principal cause was identified for eyes presenting with visual acuity (VA) ≤ 20/40.Results: A total of 4,738 persons were examined and 834 (17.6%) had cataract surgery. Intra-ocular lenses (IOLs) were used in 84.1% of the 1,299 cataract-operated eyes, with more than half of these having manual small incision surgery. Surgical coverage among the cataract blind (visual acuity [VA] < 20/200) was estimated as 72.2%. Coverage was associated with older age, literacy, and urban residence; gender was not significant. Among cataract-operated eyes, 18.7% presented with VA ≥ 20/32 and 18.0% were < 20/200. With best-corrected acuity, the corresponding percentages were 55.7% and 11.0%. Presenting and best-corrected VA ≥ 20/63 were associated with young age, literacy, and IOL surgery; urban residence and surgery in non-governmental organizations (NGO)/private facilities were also significant for presenting VA; and recent surgery was significant for best-corrected VA. Refractive error was the main cause of vision impairment/blindness in cataract-operated eyes.Conclusions: Refractive error and posterior capsule opacification, easily treatable causes of visual impairment, are common among the operated. A greater emphasis on the quality of visual acuity outcomes along with sustained efforts to provide access to affordable surgery is needed.