Comments on: All India Ophthalmological Society (AIOS) Task Force guidelines to prevent intraocular infections and cluster outbreaks after cataract surgery
A One-Year Randomized Trial Investigating the Value Of an Intervention to Enhance Adherence in Newly-Diagnosed Glaucoma Patients Receiving Prostaglandin Monotherapy and in Patients Who Are Candidates for Adjunctive Therapy
Incidence and Outcomes of Suprachoroidal Hemorrhage Following Aurolab Aqueous Drainage Implant in Adult and Pediatric Glaucoma
Journal of Glaucoma, 2020
PRCIS Postoperative suprachoroidal hemorrhage is an infrequent but devastating complication after... more PRCIS Postoperative suprachoroidal hemorrhage is an infrequent but devastating complication after non-valved aqueous drainage implant surgery and demonstrated a bimodal distribution. The final outcomes of either conservative management or surgical drainage of the hemorrhage remained poor. PURPOSE To report the incidence and outcomes of eyes developing postoperative suprachoroidal hemorrhage (PSCH) after undergoing Aurolab Aqueous Drainage Implant (AADI) surgery for adult and pediatric refractory glaucomas. MATERIALS AND METHODS In this retrospective series, case files of all patients who underwent AADI between May 2012 and December 2019 were retrieved from an electronic database. A PSCH was defined as the presence of hemorrhagic choroidal detachment, confirmed by ultrasound B scan, occurring in a closed system in the postoperative period. RESULTS Of the 986 eyes that underwent AADI during the study period, 7 (0.7%), developed PSCH (95% CI=0.3-1.6%). There were no differences in the preoperative parameters between those with and without PSCH. Of these, 4 were seen in pediatric eyes (4/288, 1.4%) and 3 in adult eyes (3/698, 0.4%) (P<0.01). Four eyes (57%) had PSCH in the immediate postoperative period (i.e. between 24 - 48▒h of AADI surgery), while the remaining 3 had onset ranging from 6-7 weeks after surgery. Anatomic risk factors were present in all eyes including hypotony (n=4), myopia (n=3), microcornea (n=2), microphthalmos (n=1), post vitrectomy (n=1) and staphyloma (n=1). Visual acuity improved in only one (14%) eye while 3 (43%) eyes developed phthisis bulbi, all in the pediatric age group. CONCLUSIONS PSCH is a rare complication following AADI and is seen in <1% eyes. The incidence is higher in the pediatric age group. Visual and anatomic outcomes are dismal following PSCH with globe salvage possible in only about half these eyes.
Trends in Prevalence of Blindness and Distance and Near Vision Impairment Over 30 Years and Contribution to the Global Burden of Disease in 2020
SSRN Electronic Journal, 2020
Background: The Vision Loss Expert Group and Global Burden of Disease Study have extensively upda... more Background: The Vision Loss Expert Group and Global Burden of Disease Study have extensively updated estimates of global vision loss burden in 2020, temporal changeover 3 decades and forecasts for 2050. Methods: A systematic review and meta-analysis was conducted of population-based datasets relevant to vision impairment (VI) from January 1980 to October 2018. Hierarchical models were fitted to estimate 2020 prevalence (with 95% uncertainty intervals, UI) of (1) mild VI (presenting visual acuity [PVA] 6/12). Findings: In 2020, an estimated 43.2 million (95% UI: 37.5-48.2 million; 55% female) people were blind, 295.3 (95% UI 267.0-325.5) million had MSVI, 257.3 (95% UI 232.2-284.7) million had mild VI, and 507.4 million (95% UI 369.3–663.8) were VI from uncorrected presbyopia. Globally among adults aged ≥50 years, age-standardised prevalence of blindness reduced by 29% between 1990 and 2020, while MSVI increased slightly (+2.4%). The number of blind people increased by 50.2% and MSVI by 91.6%. By 2050, we predict 895.5 million people blind/VI. Interpretation: It is encouraging that age-adjusted prevalence of blindness has reduced over the past 3 decades, yet due to population growth progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages. Funding Statement: Brien Holden Vision Institute. Fondation Thea. Fred Hollows Foundation. Gates Foundation. Sightsavers International. University of Heidelberg. Declaration of Interests: A.M. Bron, Allergan (C) Baush and Lomb (C), Santen (C), Thea (C) - (C) stands for consultant. J Kempen: Consultant (DSMC Chair) for Gilead. Grants and contracts from National Institutes of Health/National Eye Institute; Sight for Souls; and Christoffel Blindenmission. No other authors had conflicts to declare.
PURPOSE: To report the incidence and outcomes of hypertensive phase (HP) following Aurolab Aqueou... more PURPOSE: To report the incidence and outcomes of hypertensive phase (HP) following Aurolab Aqueous Drainage Implant (AADI) (Aurolab) surgery in adults with refractory glaucoma. DESIGN: Retrospective, noncomparative, interventional case series. METHODS: All eyes that received the AADI and had a minimum of 2-year follow-up were identified, and data of patients who had intraocular pressure (IOP) £21 mm Hg at 6 weeks (ie, the time at which the tube-ligature suture dissolves) were used for statistical analysis. HP was defined as IOP >21 mm Hg during the first 3 months after the release of the tube ligating suture (with or without medications) in the absence of tube obstruction. RESULTS: A total of 200 eyes were included in the study, and HP was seen in 64 eyes (32%) with a peak IOP (mean ± SD) of 29.6 ± 7.8 mm Hg and peak incidence at 2-3 months after surgery. HP resolved within 3 months of its onset in 60 of the 64 eyes (94%) with additional IOP-lowering medications. The cumulative success rates were 71.8% (95% CI [ 59.3%-81.2%) in HP eyes and 76.4% (95% CI [ 68.7%-82.7%) in non-HP eyes (P [ .23). Unadjusted Cox proportional hazards analysis showed that eyes experiencing HP had a marginally higher risk of failure (HR [ 1.16, 95% CI [ 0.6-2.1), but this relationship was not statistically significant (P [ .61). CONCLUSIONS: A third of eyes that underwent AADI placement experienced HP. HP was successfully managed with additional IOP-lowering medications in a majority of cases and did not have a significant influence on long-term success rate. (Am J Ophthalmol 2021;221:75-82.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Contemporary data for causes of vision impairment and blindness form an important basis of recomm... more Contemporary data for causes of vision impairment and blindness form an important basis of recommendations in public health policies. Refreshment of the Global Vision Database with recently published data sources permitted modelling of cause of vision loss data from 1990 to 2015, further disaggregation by cause, and forecasts to 2020. In this systematic review and meta-analysis, we analysed published and unpublished population-based data for the causes of vision impairment and blindness from 1980 to 2014. We identified population-based studies published before July 8, 2014, by searching online databases with no language restrictions (MEDLINE from Jan 1, 1946, and Embase from Jan 1, 1974, and the WHO Library Database). We fitted a series of regression models to estimate the proportion of moderate or severe vision impairment (defined as presenting visual acuity of <6/18 but ≥3/60 in the better eye) and blindness (presenting visual acuity of <3/60 in the better eye) by cause, age...
We thank Dr Tripathy for his interest in our recent publication 1 and the opportunity to discuss ... more We thank Dr Tripathy for his interest in our recent publication 1 and the opportunity to discuss the results in more detail. The conversion of Snellen visual acuity to logarithm of the minimum angle of resolution presents a challenge when visual acuity is <20/400. Various authors have addressed this, 2-4 and accurate conversion needs to take into consideration testing distance, contrast, and, in the case of count fingers, the size of the examiner's hand. In the current study, subjects with visual acuity of count fingers or less were assessed at a distance of 30 cm, and thus we have chosen to use the calculations of Lange et al 2 at this distance for conversion. The visual acuity data showed a skewed distribution and, therefore, all values were reported as median and interquartile range to eliminate the distortion likely to occur with mean values. Cox regression analysis was performed for the categories of moderate and severe visual loss, 5 again eliminating any distortion from the higher logarithm of the minimum angle of resolution values. We reported 42 subjects (13.8%) requiring second-line immunosuppression during the course of their disease. A range of immunosuppressive agents were used, reflecting both changing practice patterns over the course of the study and a variation in the underlying systemic associations. The subject who underwent evisceration was a woman with relapsing polychondritis. She had count fingers vision owing to complications of intermediate uveitis and subsequently developed necrotising scleritis and a perforation. Her systemic health was too poor for enucleation, and so she underwent evisceration at our center.
Background Global and regional prevalence estimates for blindness and vision impairment are impor... more Background Global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. We aimed to provide global estimates, trends, and projections of global blindness and vision impairment. Methods We did a systematic review and meta-analysis of population-based datasets relevant to global vision impairment and blindness that were published between 1980 and 2015. We fitted hierarchical models to estimate the prevalence (by age, country, and sex), in 2015, of mild visual impairment (presenting visual acuity worse than 6/12 to 6/18 inclusive), moderate to severe visual impairment (presenting visual acuity worse than 6/18 to 3/60 inclusive), blindness (presenting visual acuity worse than 3/60), and functional presbyopia (defined as presenting near vision worse than N6 or N8 at 40 cm when best-corrected distance visual acuity was better than 6/12). Findings Globally, of the 7•33 billion people alive in 2015, an estimated 36•0 million (80% uncertainty interval [UI] 12•9-65•4) were blind (crude prevalence 0•48%; 80% UI 0•17-0•87; 56% female), 216•6 million (80% UI 98•5-359•1) people had moderate to severe visual impairment (2•95%, 80% UI 1•34-4•89; 55% female), and 188•5 million (80% UI 64•5-350•2) had mild visual impairment (2•57%, 80% UI 0•88-4•77; 54% female). Functional presbyopia affected an estimated 1094•7 million (80% UI 581•1-1686•5) people aged 35 years and older, with 666•7 million (80% UI 364•9-997•6) being aged 50 years or older. The estimated number of blind people increased by 17•6%, from 30•6 million (80% UI 9•9-57•3) in 1990 to 36•0 million (80% UI 12•9-65•4) in 2015. This change was attributable to three factors, namely an increase because of population growth (38•4%), population ageing after accounting for population growth (34•6%), and reduction in age-specific prevalence (-36•7%). The number of people with moderate and severe visual impairment also increased, from 159•9 million (80% UI 68•3-270•0) in 1990 to 216•6 million (80% UI 98•5-359•1) in 2015. Interpretation There is an ongoing reduction in the age-standardised prevalence of blindness and visual impairment, yet the growth and ageing of the world's population is causing a substantial increase in number of people affected. These observations, plus a very large contribution from uncorrected presbyopia, highlight the need to scale up vision impairment alleviation efforts at all levels. Funding Brien Holden Vision Institute.
To evaluate the epidemiology of uncorrected refractive errors (URE) in adults both in the United ... more To evaluate the epidemiology of uncorrected refractive errors (URE) in adults both in the United States and globally, health outcomes impacted by URE, common barriers to treatment, and propose potential interventions. URE is the main cause of visual impairment and the second leading cause of blindness globally. Rates of URE are rising, and cause disability that reduces productivity, economic earnings, and the quality of life of affected individuals. Economic barriers, healthcare access, and sociocultural constraints are among the most fundamental barriers to correcting URE. However, innovative approaches are poised to lower rates of URE. URE is a leading cause of preventable visual impairment with serious health consequences. Numerous social and financial barriers are associated with the high prevalence of URE in low-income adults. Novel delivery programs for eyeglasses and programs to provide refractive surgery to correct refractive error could decrease rates of URE.
This study was designed to investigate the feasibility of teaching experienced surgeons to perfor... more This study was designed to investigate the feasibility of teaching experienced surgeons to perform phacoemulsification in India, a cataract-endemic area. Complications occurring during surgery and the first postoperative day were documented and evaluated. During a 1-month period, at the Aravind Eye Hospital in Madurai, India, the first 100 consecutive cataract operations performed by each of three experienced surgeons (a total of 300 cases), using phacoemulsification were prospectively evaluated. Multiple logistic regression was used to identify factors associated with intraoperative and postoperative complications. The mean age of patients was 57.4+/-9.3 years. The median best corrected preoperative visual acuity was 20/80. Mean surgical and phacoemulsification times were 15.8+/-3.7 minutes and 2.2+/-1.5 minutes, respectively. Complications occurred in 65 (21.7%) eyes. The most common was a rent in the posterior capsule, occurring in 40 (13.3%) eyes. There were significant variatio...
The histologic effects of various Neodymium:YAG laser energy levels were evaluated after iridotom... more The histologic effects of various Neodymium:YAG laser energy levels were evaluated after iridotomy formation in cynomolgus monkey eyes. Scanning election microscopy of the corneal endothelium above the treated areas revealed no significant cell loss or pleomorphism when compared to the adjacent untreated areas. Light and phase contrast microscopy demonstrated closure of the iridotomies in most cases by a bridge of iris pigment epithelium. In several specimens, stromal tissue and pigment laden cells were present over the attenuated iris pigment epithelium. There were four lens opacities with rupture of the anterior lens capsule and anterior epithelial cell hyperplasia in one. No damage was apparent in the trabecular meshwork or retina with light microscopy or fluorescein angiography.
A287 scheduled for an office visit within the next 3 weeks for an anti-VEGF injection or monitori... more A287 scheduled for an office visit within the next 3 weeks for an anti-VEGF injection or monitoring. Additionally, a survey was administered to 75 patients with NVAMD who were aged ≥ 50 years and had received ≥ 1 anti-VEGF injection in the past 6 months. Furthermore, telephone interviews were conducted with 13 caregivers of patients with NVAMD. Results: 56 physicians provided data for 221 patients with NVAMD. Management of patients with NVAMD comprised 20% of the health care staff's working week, with an average of 24 staff members involved. An average patient visit for management of NVAMD was 90 minutes (range: 13 minutes to > 4 hours). Patients reported an average time commitment per visit of almost 12 hours, including preappointment preparation (16 minutes), travel (66 minutes), waiting time (37 minutes), treatment time (43 minutes), and recovery (9 hours). Caregivers reported taking time away from work (> 20%) and personal activities (> 25%) to accompany patients to appointments. ConClusions: NVAMD management imposes a substantial time burden on physicians and other staff members, as well as patients and caregivers. There may be a need for additional support and/ or reimbursement for services required by patients and caregivers, as well as those provided by physicians.
Transactions of the American Ophthalmological Society, 1991
We performed a prospective study evaluating the 2-year success rate of extracapsular cataract sur... more We performed a prospective study evaluating the 2-year success rate of extracapsular cataract surgery and posterior chamber IOL insertion performed in 610 eyes by an experienced surgeon in the Nepal Eye Hospital, Kathmandu, Nepal. All patients were followed for 2 years. All eyes underwent manual irrigation and aspiration of cortical materials with the insertion of a modified J-loop posterior chamber IOL. Almost one half of eyes had final uncorrected visual acuities of 20/50 or better. Devastating complications, including retinal detachment, corneal decompensation, and endophthalmitis, occurred in 7 (1.2%) eyes. Extracapsular cataract surgery with IOL implantation appears to be a possible alternative in underdeveloped nations where the prevalence of cataract is high and aphakic spectacles are not easily obtained by poor patients and may be lost or broken. The procedure may improve the quality of vision, and therefore the quality of life, in those patients able to obtain pseudophakic ...
To determine the prevalence of glaucoma and risk factors for primary open-angle glaucoma in a rur... more To determine the prevalence of glaucoma and risk factors for primary open-angle glaucoma in a rural population of southern India. Design: A population-based cross-sectional study. Participants: A total of 5150 subjects aged 40 years and older from 50 clusters representative of three southern districts of Tamil Nadu in southern India. Methods: All participants had a comprehensive eye examination at the base hospital, including visual acuity using logarithm of the minimum angle of resolution illiterate E charts and refraction, slit-lamp biomicroscopy, gonioscopy, applanation tonometry, dilated fundus examinations, and automated central 24-2 full-threshold perimetry. Main Outcome Measures: Definite primary open-angle glaucoma (POAG) was defined as angles open on gonioscopy and glaucomatous optic disc changes with matching visual field defects, whereas ocular hypertension was defined as intraocular pressure (IOP) greater than 21 mmHg without glaucomatous optic disc damage and visual field defects in the presence of an open angle. Manifest primary angle-closure glaucoma (PACG) was defined as glaucomatous optic disc damage or glaucomatous visual field defects with the anterior chamber angle partly or totally closed, appositional angle closure or synechiae in the angle, and absence of signs of secondary angle closure. Secondary glaucoma was defined as glaucomatous optic nerve damage and/or visual field abnormalities suggestive of glaucoma with ocular disorders that contribute to a secondary elevation in IOP. Results: The prevalence (95% confidence interval) of any glaucoma was 2.6% (2.2, 3.0), of POAG it was 1.7% (1.3, 2.1), and if PACG it was 0.5% (0.3, 0.7), and secondary glaucoma excluding pseudoexfoliation was 0.3% (0.2,0.5). On multivariate analysis, increasing age, male gender, myopia greater than 1 diopter, and pseudoexfoliation were significantly associated with POAG. After best correction, 18 persons (20.9%) with POAG were blind in either eye because of glaucoma, including 6 who were bilaterally blind and an additional 12 persons with unilateral blindness because of glaucomatous optic neuropathy in that eye. Of those identified with POAG, 93.0% had not been previously diagnosed with POAG. Conclusions: The prevalence of glaucoma in this population is not lower than that reported for white populations elsewhere. A large proportion of those with POAG had not been previously diagnosed. One fifth of those with POAG had blindness in one or both eyes from glaucoma. Early detection of glaucoma in this population will reduce the burden of blindness in India.
Comments on: All India Ophthalmological Society (AIOS) Task Force guidelines to prevent intraocular infections and cluster outbreaks after cataract surgery
A One-Year Randomized Trial Investigating the Value Of an Intervention to Enhance Adherence in Newly-Diagnosed Glaucoma Patients Receiving Prostaglandin Monotherapy and in Patients Who Are Candidates for Adjunctive Therapy
Incidence and Outcomes of Suprachoroidal Hemorrhage Following Aurolab Aqueous Drainage Implant in Adult and Pediatric Glaucoma
Journal of Glaucoma, 2020
PRCIS Postoperative suprachoroidal hemorrhage is an infrequent but devastating complication after... more PRCIS Postoperative suprachoroidal hemorrhage is an infrequent but devastating complication after non-valved aqueous drainage implant surgery and demonstrated a bimodal distribution. The final outcomes of either conservative management or surgical drainage of the hemorrhage remained poor. PURPOSE To report the incidence and outcomes of eyes developing postoperative suprachoroidal hemorrhage (PSCH) after undergoing Aurolab Aqueous Drainage Implant (AADI) surgery for adult and pediatric refractory glaucomas. MATERIALS AND METHODS In this retrospective series, case files of all patients who underwent AADI between May 2012 and December 2019 were retrieved from an electronic database. A PSCH was defined as the presence of hemorrhagic choroidal detachment, confirmed by ultrasound B scan, occurring in a closed system in the postoperative period. RESULTS Of the 986 eyes that underwent AADI during the study period, 7 (0.7%), developed PSCH (95% CI=0.3-1.6%). There were no differences in the preoperative parameters between those with and without PSCH. Of these, 4 were seen in pediatric eyes (4/288, 1.4%) and 3 in adult eyes (3/698, 0.4%) (P<0.01). Four eyes (57%) had PSCH in the immediate postoperative period (i.e. between 24 - 48▒h of AADI surgery), while the remaining 3 had onset ranging from 6-7 weeks after surgery. Anatomic risk factors were present in all eyes including hypotony (n=4), myopia (n=3), microcornea (n=2), microphthalmos (n=1), post vitrectomy (n=1) and staphyloma (n=1). Visual acuity improved in only one (14%) eye while 3 (43%) eyes developed phthisis bulbi, all in the pediatric age group. CONCLUSIONS PSCH is a rare complication following AADI and is seen in <1% eyes. The incidence is higher in the pediatric age group. Visual and anatomic outcomes are dismal following PSCH with globe salvage possible in only about half these eyes.
Trends in Prevalence of Blindness and Distance and Near Vision Impairment Over 30 Years and Contribution to the Global Burden of Disease in 2020
SSRN Electronic Journal, 2020
Background: The Vision Loss Expert Group and Global Burden of Disease Study have extensively upda... more Background: The Vision Loss Expert Group and Global Burden of Disease Study have extensively updated estimates of global vision loss burden in 2020, temporal changeover 3 decades and forecasts for 2050. Methods: A systematic review and meta-analysis was conducted of population-based datasets relevant to vision impairment (VI) from January 1980 to October 2018. Hierarchical models were fitted to estimate 2020 prevalence (with 95% uncertainty intervals, UI) of (1) mild VI (presenting visual acuity [PVA] 6/12). Findings: In 2020, an estimated 43.2 million (95% UI: 37.5-48.2 million; 55% female) people were blind, 295.3 (95% UI 267.0-325.5) million had MSVI, 257.3 (95% UI 232.2-284.7) million had mild VI, and 507.4 million (95% UI 369.3–663.8) were VI from uncorrected presbyopia. Globally among adults aged ≥50 years, age-standardised prevalence of blindness reduced by 29% between 1990 and 2020, while MSVI increased slightly (+2.4%). The number of blind people increased by 50.2% and MSVI by 91.6%. By 2050, we predict 895.5 million people blind/VI. Interpretation: It is encouraging that age-adjusted prevalence of blindness has reduced over the past 3 decades, yet due to population growth progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages. Funding Statement: Brien Holden Vision Institute. Fondation Thea. Fred Hollows Foundation. Gates Foundation. Sightsavers International. University of Heidelberg. Declaration of Interests: A.M. Bron, Allergan (C) Baush and Lomb (C), Santen (C), Thea (C) - (C) stands for consultant. J Kempen: Consultant (DSMC Chair) for Gilead. Grants and contracts from National Institutes of Health/National Eye Institute; Sight for Souls; and Christoffel Blindenmission. No other authors had conflicts to declare.
PURPOSE: To report the incidence and outcomes of hypertensive phase (HP) following Aurolab Aqueou... more PURPOSE: To report the incidence and outcomes of hypertensive phase (HP) following Aurolab Aqueous Drainage Implant (AADI) (Aurolab) surgery in adults with refractory glaucoma. DESIGN: Retrospective, noncomparative, interventional case series. METHODS: All eyes that received the AADI and had a minimum of 2-year follow-up were identified, and data of patients who had intraocular pressure (IOP) £21 mm Hg at 6 weeks (ie, the time at which the tube-ligature suture dissolves) were used for statistical analysis. HP was defined as IOP >21 mm Hg during the first 3 months after the release of the tube ligating suture (with or without medications) in the absence of tube obstruction. RESULTS: A total of 200 eyes were included in the study, and HP was seen in 64 eyes (32%) with a peak IOP (mean ± SD) of 29.6 ± 7.8 mm Hg and peak incidence at 2-3 months after surgery. HP resolved within 3 months of its onset in 60 of the 64 eyes (94%) with additional IOP-lowering medications. The cumulative success rates were 71.8% (95% CI [ 59.3%-81.2%) in HP eyes and 76.4% (95% CI [ 68.7%-82.7%) in non-HP eyes (P [ .23). Unadjusted Cox proportional hazards analysis showed that eyes experiencing HP had a marginally higher risk of failure (HR [ 1.16, 95% CI [ 0.6-2.1), but this relationship was not statistically significant (P [ .61). CONCLUSIONS: A third of eyes that underwent AADI placement experienced HP. HP was successfully managed with additional IOP-lowering medications in a majority of cases and did not have a significant influence on long-term success rate. (Am J Ophthalmol 2021;221:75-82.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Contemporary data for causes of vision impairment and blindness form an important basis of recomm... more Contemporary data for causes of vision impairment and blindness form an important basis of recommendations in public health policies. Refreshment of the Global Vision Database with recently published data sources permitted modelling of cause of vision loss data from 1990 to 2015, further disaggregation by cause, and forecasts to 2020. In this systematic review and meta-analysis, we analysed published and unpublished population-based data for the causes of vision impairment and blindness from 1980 to 2014. We identified population-based studies published before July 8, 2014, by searching online databases with no language restrictions (MEDLINE from Jan 1, 1946, and Embase from Jan 1, 1974, and the WHO Library Database). We fitted a series of regression models to estimate the proportion of moderate or severe vision impairment (defined as presenting visual acuity of <6/18 but ≥3/60 in the better eye) and blindness (presenting visual acuity of <3/60 in the better eye) by cause, age...
We thank Dr Tripathy for his interest in our recent publication 1 and the opportunity to discuss ... more We thank Dr Tripathy for his interest in our recent publication 1 and the opportunity to discuss the results in more detail. The conversion of Snellen visual acuity to logarithm of the minimum angle of resolution presents a challenge when visual acuity is <20/400. Various authors have addressed this, 2-4 and accurate conversion needs to take into consideration testing distance, contrast, and, in the case of count fingers, the size of the examiner's hand. In the current study, subjects with visual acuity of count fingers or less were assessed at a distance of 30 cm, and thus we have chosen to use the calculations of Lange et al 2 at this distance for conversion. The visual acuity data showed a skewed distribution and, therefore, all values were reported as median and interquartile range to eliminate the distortion likely to occur with mean values. Cox regression analysis was performed for the categories of moderate and severe visual loss, 5 again eliminating any distortion from the higher logarithm of the minimum angle of resolution values. We reported 42 subjects (13.8%) requiring second-line immunosuppression during the course of their disease. A range of immunosuppressive agents were used, reflecting both changing practice patterns over the course of the study and a variation in the underlying systemic associations. The subject who underwent evisceration was a woman with relapsing polychondritis. She had count fingers vision owing to complications of intermediate uveitis and subsequently developed necrotising scleritis and a perforation. Her systemic health was too poor for enucleation, and so she underwent evisceration at our center.
Background Global and regional prevalence estimates for blindness and vision impairment are impor... more Background Global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. We aimed to provide global estimates, trends, and projections of global blindness and vision impairment. Methods We did a systematic review and meta-analysis of population-based datasets relevant to global vision impairment and blindness that were published between 1980 and 2015. We fitted hierarchical models to estimate the prevalence (by age, country, and sex), in 2015, of mild visual impairment (presenting visual acuity worse than 6/12 to 6/18 inclusive), moderate to severe visual impairment (presenting visual acuity worse than 6/18 to 3/60 inclusive), blindness (presenting visual acuity worse than 3/60), and functional presbyopia (defined as presenting near vision worse than N6 or N8 at 40 cm when best-corrected distance visual acuity was better than 6/12). Findings Globally, of the 7•33 billion people alive in 2015, an estimated 36•0 million (80% uncertainty interval [UI] 12•9-65•4) were blind (crude prevalence 0•48%; 80% UI 0•17-0•87; 56% female), 216•6 million (80% UI 98•5-359•1) people had moderate to severe visual impairment (2•95%, 80% UI 1•34-4•89; 55% female), and 188•5 million (80% UI 64•5-350•2) had mild visual impairment (2•57%, 80% UI 0•88-4•77; 54% female). Functional presbyopia affected an estimated 1094•7 million (80% UI 581•1-1686•5) people aged 35 years and older, with 666•7 million (80% UI 364•9-997•6) being aged 50 years or older. The estimated number of blind people increased by 17•6%, from 30•6 million (80% UI 9•9-57•3) in 1990 to 36•0 million (80% UI 12•9-65•4) in 2015. This change was attributable to three factors, namely an increase because of population growth (38•4%), population ageing after accounting for population growth (34•6%), and reduction in age-specific prevalence (-36•7%). The number of people with moderate and severe visual impairment also increased, from 159•9 million (80% UI 68•3-270•0) in 1990 to 216•6 million (80% UI 98•5-359•1) in 2015. Interpretation There is an ongoing reduction in the age-standardised prevalence of blindness and visual impairment, yet the growth and ageing of the world's population is causing a substantial increase in number of people affected. These observations, plus a very large contribution from uncorrected presbyopia, highlight the need to scale up vision impairment alleviation efforts at all levels. Funding Brien Holden Vision Institute.
To evaluate the epidemiology of uncorrected refractive errors (URE) in adults both in the United ... more To evaluate the epidemiology of uncorrected refractive errors (URE) in adults both in the United States and globally, health outcomes impacted by URE, common barriers to treatment, and propose potential interventions. URE is the main cause of visual impairment and the second leading cause of blindness globally. Rates of URE are rising, and cause disability that reduces productivity, economic earnings, and the quality of life of affected individuals. Economic barriers, healthcare access, and sociocultural constraints are among the most fundamental barriers to correcting URE. However, innovative approaches are poised to lower rates of URE. URE is a leading cause of preventable visual impairment with serious health consequences. Numerous social and financial barriers are associated with the high prevalence of URE in low-income adults. Novel delivery programs for eyeglasses and programs to provide refractive surgery to correct refractive error could decrease rates of URE.
This study was designed to investigate the feasibility of teaching experienced surgeons to perfor... more This study was designed to investigate the feasibility of teaching experienced surgeons to perform phacoemulsification in India, a cataract-endemic area. Complications occurring during surgery and the first postoperative day were documented and evaluated. During a 1-month period, at the Aravind Eye Hospital in Madurai, India, the first 100 consecutive cataract operations performed by each of three experienced surgeons (a total of 300 cases), using phacoemulsification were prospectively evaluated. Multiple logistic regression was used to identify factors associated with intraoperative and postoperative complications. The mean age of patients was 57.4+/-9.3 years. The median best corrected preoperative visual acuity was 20/80. Mean surgical and phacoemulsification times were 15.8+/-3.7 minutes and 2.2+/-1.5 minutes, respectively. Complications occurred in 65 (21.7%) eyes. The most common was a rent in the posterior capsule, occurring in 40 (13.3%) eyes. There were significant variatio...
The histologic effects of various Neodymium:YAG laser energy levels were evaluated after iridotom... more The histologic effects of various Neodymium:YAG laser energy levels were evaluated after iridotomy formation in cynomolgus monkey eyes. Scanning election microscopy of the corneal endothelium above the treated areas revealed no significant cell loss or pleomorphism when compared to the adjacent untreated areas. Light and phase contrast microscopy demonstrated closure of the iridotomies in most cases by a bridge of iris pigment epithelium. In several specimens, stromal tissue and pigment laden cells were present over the attenuated iris pigment epithelium. There were four lens opacities with rupture of the anterior lens capsule and anterior epithelial cell hyperplasia in one. No damage was apparent in the trabecular meshwork or retina with light microscopy or fluorescein angiography.
A287 scheduled for an office visit within the next 3 weeks for an anti-VEGF injection or monitori... more A287 scheduled for an office visit within the next 3 weeks for an anti-VEGF injection or monitoring. Additionally, a survey was administered to 75 patients with NVAMD who were aged ≥ 50 years and had received ≥ 1 anti-VEGF injection in the past 6 months. Furthermore, telephone interviews were conducted with 13 caregivers of patients with NVAMD. Results: 56 physicians provided data for 221 patients with NVAMD. Management of patients with NVAMD comprised 20% of the health care staff's working week, with an average of 24 staff members involved. An average patient visit for management of NVAMD was 90 minutes (range: 13 minutes to > 4 hours). Patients reported an average time commitment per visit of almost 12 hours, including preappointment preparation (16 minutes), travel (66 minutes), waiting time (37 minutes), treatment time (43 minutes), and recovery (9 hours). Caregivers reported taking time away from work (> 20%) and personal activities (> 25%) to accompany patients to appointments. ConClusions: NVAMD management imposes a substantial time burden on physicians and other staff members, as well as patients and caregivers. There may be a need for additional support and/ or reimbursement for services required by patients and caregivers, as well as those provided by physicians.
Transactions of the American Ophthalmological Society, 1991
We performed a prospective study evaluating the 2-year success rate of extracapsular cataract sur... more We performed a prospective study evaluating the 2-year success rate of extracapsular cataract surgery and posterior chamber IOL insertion performed in 610 eyes by an experienced surgeon in the Nepal Eye Hospital, Kathmandu, Nepal. All patients were followed for 2 years. All eyes underwent manual irrigation and aspiration of cortical materials with the insertion of a modified J-loop posterior chamber IOL. Almost one half of eyes had final uncorrected visual acuities of 20/50 or better. Devastating complications, including retinal detachment, corneal decompensation, and endophthalmitis, occurred in 7 (1.2%) eyes. Extracapsular cataract surgery with IOL implantation appears to be a possible alternative in underdeveloped nations where the prevalence of cataract is high and aphakic spectacles are not easily obtained by poor patients and may be lost or broken. The procedure may improve the quality of vision, and therefore the quality of life, in those patients able to obtain pseudophakic ...
To determine the prevalence of glaucoma and risk factors for primary open-angle glaucoma in a rur... more To determine the prevalence of glaucoma and risk factors for primary open-angle glaucoma in a rural population of southern India. Design: A population-based cross-sectional study. Participants: A total of 5150 subjects aged 40 years and older from 50 clusters representative of three southern districts of Tamil Nadu in southern India. Methods: All participants had a comprehensive eye examination at the base hospital, including visual acuity using logarithm of the minimum angle of resolution illiterate E charts and refraction, slit-lamp biomicroscopy, gonioscopy, applanation tonometry, dilated fundus examinations, and automated central 24-2 full-threshold perimetry. Main Outcome Measures: Definite primary open-angle glaucoma (POAG) was defined as angles open on gonioscopy and glaucomatous optic disc changes with matching visual field defects, whereas ocular hypertension was defined as intraocular pressure (IOP) greater than 21 mmHg without glaucomatous optic disc damage and visual field defects in the presence of an open angle. Manifest primary angle-closure glaucoma (PACG) was defined as glaucomatous optic disc damage or glaucomatous visual field defects with the anterior chamber angle partly or totally closed, appositional angle closure or synechiae in the angle, and absence of signs of secondary angle closure. Secondary glaucoma was defined as glaucomatous optic nerve damage and/or visual field abnormalities suggestive of glaucoma with ocular disorders that contribute to a secondary elevation in IOP. Results: The prevalence (95% confidence interval) of any glaucoma was 2.6% (2.2, 3.0), of POAG it was 1.7% (1.3, 2.1), and if PACG it was 0.5% (0.3, 0.7), and secondary glaucoma excluding pseudoexfoliation was 0.3% (0.2,0.5). On multivariate analysis, increasing age, male gender, myopia greater than 1 diopter, and pseudoexfoliation were significantly associated with POAG. After best correction, 18 persons (20.9%) with POAG were blind in either eye because of glaucoma, including 6 who were bilaterally blind and an additional 12 persons with unilateral blindness because of glaucomatous optic neuropathy in that eye. Of those identified with POAG, 93.0% had not been previously diagnosed with POAG. Conclusions: The prevalence of glaucoma in this population is not lower than that reported for white populations elsewhere. A large proportion of those with POAG had not been previously diagnosed. One fifth of those with POAG had blindness in one or both eyes from glaucoma. Early detection of glaucoma in this population will reduce the burden of blindness in India.
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Papers by Alan L Robin