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David S Friedman

Publications and source records attributed to David S Friedman.

At least 37 records · Page 2Linked to original sources
PubMed2004

Prevalence of cataract and pseudophakia/aphakia among adults in the United States.

OBJECTIVES: To determine the prevalence of cataract and pseudophakia/aphakia in the United States and to project the expected change in these prevalence figures by 2020. METHODS: Summary prevalence estimates of cataract and of pseudophakia/aphakia were prepared separately for black, white, and Hispanic persons (for whom only cataract surgery data were available) in 5-year age intervals starting at 40 years for women and men. The estimates were based on a standardized definition of various types of cataract: cortical, greater than 25% of the lens involved; posterior subcapsular, present according to the grading system used in each study; and nuclear, greater than or equal to the penultimate grade in the system used. Data were collected from major population-based studies in the United States, and, where appropriate, Australia, Barbados, and Western Europe. The age-, gender-, and race/ethnicity-specific rates were applied to 2000 US Census data, and projected population figures for 2020, to obtain overall estimates. RESULTS: An estimated 20.5 million (17.2%) Americans older than 40 years have cataract in either eye, and 6.1 million (5.1%) have pseudophakia/aphakia. Women have a significantly (odds ratio = 1.37; 95% confidence interval, 1.26-1.50) higher age-adjusted prevalence of cataract than men in the United States. The total number of persons who have cataract is estimated to rise to 30.1 million by 2020; and for those who are expected to have pseudophakia/aphakia, to 9.5 million. CONCLUSION: The number of Americans affected by cataract and undergoing cataract surgery will dramatically increase over the next 20 years as the US population ages.

Adult↗
PubMed2004

Prevalence of open-angle glaucoma among adults in the United States.

OBJECTIVE: To estimate the prevalence and distribution of open-angle glaucoma (OAG) in the United States by age, race/ethnicity, and gender. METHODS: Summary prevalence estimates of OAG were prepared separately for black, Hispanic, and white subjects in 5-year age intervals starting at 40 years. The estimated rates were based on a meta-analysis of recent population-based studies in the United States, Australia, and Europe. These rates were applied to 2000 US census data and to projected US population figures for 2020 to estimate the number of the US population with OAG. RESULTS: The overall prevalence of OAG in the US population 40 years and older is estimated to be 1.86% (95% confidence interval, 1.75%-1.96%), with 1.57 million white and 398 000 black persons affected. After applying race-, age-, and gender-specific rates to the US population as determined in the 2000 US census, we estimated that OAG affects 2.22 million US citizens. Owing to the rapidly aging population, the number with OAG will increase by 50% to 3.36 million in 2020. Black subjects had almost 3 times the age-adjusted prevalence of glaucoma than white subjects. CONCLUSIONS: Open-angle glaucoma affects more than 2 million individuals in the United States. Owing to the rapid aging of the US population, this number will increase to more than 3 million by 2020.

Adult↗
PubMed2004

Prevalence of age-related macular degeneration in the United States.

OBJECTIVE: To estimate the prevalence and distribution of age-related macular degeneration (AMD) in the United States by age, race/ethnicity, and gender. METHODS: Summary prevalence estimates of drusen 125 microm or larger, neovascular AMD, and geographic atrophy were prepared separately for black and white persons in 5-year age intervals starting at 40 years. The estimated rates were based on a meta-analysis of recent population-based studies in the United States, Australia, and Europe. These rates were applied to 2000 US Census data and to projected US population figures for 2020 to estimate the number of the US population with drusen and AMD. RESULTS: The overall prevalence of neovascular AMD and/or geographic atrophy in the US population 40 years and older is estimated to be 1.47% (95% confidence interval, 1.38%-1.55%), with 1.75 million citizens having AMD. The prevalence of AMD increased dramatically with age, with more than 15% of the white women older than 80 years having neovascular AMD and/or geographic atrophy. More than 7 million individuals had drusen measuring 125 microm or larger and were, therefore, at substantial risk of developing AMD. Owing to the rapidly aging population, the number of persons having AMD will increase by 50% to 2.95 million in 2020. Age-related macular degeneration was far more prevalent among white than among black persons. CONCLUSION: Age-related macular degeneration affects more than 1.75 million individuals in the United States. Owing to the rapid aging of the US population, this number will increase to almost 3 million by 2020.

Adult↗
PubMed2004

Racial variations in causes of vision loss in nursing homes: The Salisbury Eye Evaluation in Nursing Home Groups (SEEING) Study.

OBJECTIVE: To determine the prevalence and causes of low vision in a large sample of nursing home residents. METHODS: Twenty-eight nursing homes on the Eastern Shore of Maryland and Delaware were enrolled in a clinical trial to assess the impact of vision restoration/rehabilitation on nursing home residents. Visual acuity was measured using both recognition charts and preferential looking techniques. An ophthalmologist examined all residents with visual acuity worse than 20/40 in the better-seeing eye and determined the primary cause for decreased vision. Results are reported for the better-seeing eye. RESULTS: Of 2544 eligible residents, 1591 (63%) participated, but 286 residents were unable to respond to visual acuity testing. Of the remaining 1307 residents, 496 (37%) had best-corrected visual acuity worse than 20/40 in the better-seeing eye. Causes were ascribed for 412 subjects. Rates of low vision were similar between African American subjects and white subjects (39% and 38%, respectively; age-adjusted P =.18). Cataract was the leading cause of low vision, responsible for 37% of low vision among white subjects and 54% of low vision among African American subjects. Macular degeneration was responsible for 29% of low vision among white subjects but only 7% among African American subjects. Glaucoma caused low vision in 4% of white subjects and 10% of African American subjects. Refractive error was not a frequent cause of low vision in nursing home residents. CONCLUSIONS: Low vision is highly prevalent among nursing home residents, with 37% having visual acuity worse than 20/40 in the better-seeing eye. Differences in causes of low vision between African American subjects and white subjects were noted, with African American subjects more likely to have vision loss on the basis of cataract, a readily treated condition. Appropriate interventions for nursing home residents, who face significant obstacles in accessing eye care services, have the potential to improve the quality of life of this at-risk older population.

Aged↗
PubMed2004

Risk assessment in the management of patients with ocular hypertension.

PURPOSE: To develop a model for estimating the global risk of disease progression in patients with ocular hypertension and to calculate the "number-needed-to-treat" (NNT) to prevent progression to blindness as an aid to practitioners in clinical decision making. DESIGN: Development of a mathematical model for estimating risk of glaucoma progression. METHODS: Population-based studies of patients with ocular hypertension and glaucoma were reviewed by a panel of glaucoma specialists. Measures of disease progression risks derived from three long-term studies and assumptions based on the available data were used to estimate the risk of progression from ocular hypertension to glaucoma and glaucoma to unilateral blindness for untreated and treated patients over a 15-year period. Using these estimates, the NNT (1/absolute risk reduction on treatment) to prevent unilateral blindness in one patient with ocular hypertension was calculated. RESULTS: In untreated patients, the estimated risk of progression from ocular hypertension to unilateral blindness was 1.5% to 10.5% and in treated patients, the estimated risk of progression was 0.3% to 2.4% over 15 years. From these estimates, between 12 and 83 patients with ocular hypertension will require treatment to prevent one patient from progressing to unilateral blindness over a 15-year period. CONCLUSION: Global risk assessment that incorporates all available data plays a vital role in managing patients with ocular hypertension. A more precise understanding of long-term vision loss should be factored into decisions pertaining to the initiation of glaucoma therapy. Undoubtedly, these estimates will evolve and change with the availability of new population-based epidemiologic information and improvements in multivariable model testing.

Blindness↗
PubMed2004

Applying an evidence-based approach to the management of patients with ocular hypertension: evaluating and synthesizing published evidence.

PURPOSE: The use of evidence-based medicine in managing patients with ocular hypertension has been constrained by the limited availability of high-quality data from controlled clinical trials and by limited formal training of clinicians in evaluating published evidence. This article will provide strategies and techniques to evaluate critically the quality of published research, synthesize the findings, and integrate published evidence in the care of patients with ocular hypertension. DESIGN: Review of the published literature and consensus of a panel of experts. METHODS: The published literature on evidence-based medicine was reviewed. Strategies and techniques in evaluating the quality of evidence and how to integrate evidence into the practice setting using the following three major questions were discussed by a panel of experts: Are the results of the study valid? What are the results? Do the study outcomes apply to individual patient care? RESULTS: Approaches to assessing study validity and the importance of considering the size of the treatment effect and precision of the effect size were detailed. The importance of using the "number-needed-to-treat" as a tool for translating results of clinical trials to individual patient care and the "number-needed-to-harm" as a method of comparing the potential benefit and harm of a given therapy was acknowledged. CONCLUSION: As the volume of high-quality data increases, the information provided herein may help ophthalmologists apply evidence-based medicine techniques as they seek to optimize the care of individual patients with ocular hypertension.

Evidence-Based Medicine↗
PubMed2004

An evidence-based assessment of risk factors for the progression of ocular hypertension and glaucoma.

PURPOSE: To critically review the existing literature concerning risk factors for progression of ocular hypertension and glaucoma to assist in assigning levels of risk for individual patients. DESIGN: Evidence-based review. METHODS: A panel of physicians specializing in treatment of glaucoma patients was convened to critically analyze published population-based studies of ocular hypertension and glaucoma progression. The strength of evidence in support of reported risk factors was weighed. RESULTS: Many putative risk factors for progression of ocular hypertension or glaucoma have been reported in the literature. The risk factors most strongly supported by evidence are higher intraocular pressure (IOP), greater cup-to-disk ratio, thinner central corneal measurement, and older age. Black race does not appear to be an independent risk factor, although black individuals tend to have thinner corneas, greater cup-to-disk ratios, and higher IOP, which increase their risk. The limited number of studies in which other suspected risk factors are reported prevents drawing firm conclusions about their importance at this time. CONCLUSIONS: Only a subset of patients with ocular hypertension will eventually develop glaucoma. Decisions regarding the implementation and extent of therapy for ocular hypertension can be difficult and require an understanding of the relative importance of risk factors for progression. This review discusses the strength of evidence supporting reported risk factors and may be useful in assessing the risk for progression of individual patients.

Disease Progression↗
PubMed2004

Glaucoma risk factor assessment and prevention: lessons from coronary heart disease.

PURPOSE: To determine whether multivariable risk factor assessment can be as successful in developing disease prevention strategies in patients with ocular hypertension as it has been in patients at risk for coronary heart disease (CHD). DESIGN: From a literature review of the evolution of the global risk assessment model for CHD, parallels are drawn to the evolution of a global risk assessment methodology for glaucoma. METHODS: This article summarizes the literature on global risk assessment and prevention of CHD in clinical practice, discusses the development of glaucoma risk assessment based on available trial and population data, and reviews the potential for prevention strategies founded on the cardiovascular disease model. RESULTS: To improve risk assessment in glaucoma and develop disease management strategies for patients with ocular hypertension, it is first necessary to identify and quantify levels of risk associated with factors that predict disease progression. In addition, the incidence of glaucoma and the average person's life expectancy based on his or her age are needed. Finally, it is necessary to quantify how long it takes to develop a visual defect that affects quality of life once a person develops glaucoma. CONCLUSION: The systematic application of epidemiologic data to CHD risk factor models provides insights into how global risk assessment can be incorporated into treatment recommendations for managing individuals with glaucoma. It is hoped that ophthalmologists can use the results of future clinical trials and long-term studies to develop disease prevention strategies in patients with ocular hypertension based on multivariable risk assessment.

Coronary Disease↗
PubMed2004

Long-term outcomes in asians after acute primary angle closure.

PURPOSE: To determine the long-term outcome of Asian eyes with an acute attack of primary angle closure (APAC) and to identify risk factors at presentation associated with the development of glaucomatous optic nerve damage. DESIGN: Cross-sectional observational case series. PARTICIPANTS: Ninety individuals who were initially seen with APAC 4 to 10 years previously at 2 Singapore hospitals. METHODS: All subjects underwent a complete eye examination, including visual acuity, visual field testing, dilated eye examination, and optic nerve head photography. The optic discs were judged clinically and photographically as to whether there was glaucomatous optic neuropathy present, and visual fields were assessed for corresponding visual field loss. All visual fields and optic nerve photographs underwent a second evaluation by an experienced, but masked, glaucoma specialist, who assessed whether the changes were compatible with glaucoma. MAIN OUTCOME MEASURES: The main outcome measures were blindness (defined as best-corrected visual acuity worse than 6/60 and/or central visual field of less than 20 degrees in the attack eye) and glaucomatous optic neuropathy (GON). RESULTS: A total of 90 of 170 eligible subjects (65.2%) were examined. All subjects were Asian and were predominantly Chinese (78 subjects [86.7%]). There were 61 females (67.8%), and the age of the subjects was 62.0+/-9.0 years (mean +/- standard deviation) at the time of APAC, with a mean duration of 6.3+/-1.5 years from the time of the APAC episode to the study examination. Sixteen (17.8%) subjects were blind in the attack eye; half of the cases of blindness were caused by glaucoma. Forty-three subjects (47.8%) had GON, with 13 eyes (15.5%) having markedly cupped optic discs (cup-to-disc ratio >0.9). Thirty-eight eyes (58%) had best-corrected vision worse than 6/9, with cataract responsible for close to half the cases of poor vision. There were no identifiable risk factors related to the APAC episode that were significantly associated with the presence of GON. CONCLUSIONS: Several years after being seen with APAC, 17.8% of subjects examined were blind in the attack eye, and almost half had glaucomatous optic nerve damage. Vision was also reduced in a large number of individuals, largely from unoperated cataract. Subjects with APAC would benefit from regular follow-up to monitor for visual field decline and glaucoma development.

Acute Disease↗
PubMed2004

The utilization of eye care services by persons with glaucoma in rural south India.

PURPOSE: To determine utilization of eye care services, in particular those relating to glaucoma, in a rural population of southern India aged 40 years or older. METHODS: A total of 5,150 subjects aged 40 years or older selected through a random cluster sampling technique from three districts in southern India underwent detailed ocular examinations for vision impairment, blindness, and ocular morbidity. Information regarding previous use of eye care services was collected from this population through a questionnaire administered by trained social workers prior to ocular examinations. RESULTS: One thousand eight hundred and twenty-seven persons (35.5%) gave a history of prior eye examinations, primarily from a general hospital (n = 1,073, 58.7%). Increasing age and education were associated with increased utilization of eye care services. Among the 3,323 persons who had never sought eye care, 912 (27.4%) had felt the need to have an eye examination but did not do so. Only one third of persons with vision impairment, cataracts, refractive errors, and glaucoma had previously utilized services. Of the 64 subjects diagnosed as having primary open-angle glaucoma, 32 (50%) had previously seen an ophthalmologist, but none had had an eye examination within 1 year before the study. Only six (19%) of the 32 had been diagnosed as having glaucoma (9% of all subjects found to have glaucoma in the survey). Thirteen (20.3%) of the 64 subjects were blind in either eye due to glaucoma, including one person who was bilaterally blind. CONCLUSIONS: A large proportion of persons in a rural population of southern India who require eye care are currently not utilizing existing eye care services. Strategies to improve the uptake of services are required to reduce the burden of blindness due to glaucoma in southern India.

Adult↗
PubMed2003

Potential public health impact of Age-Related Eye Disease Study results: AREDS report no. 11.

OBJECTIVE: To estimate the potential public health impact of the findings of the Age-Related Eye Disease Study (AREDS) on reducing the number of persons developing advanced age-related macular degeneration (AMD) during the next 5 years in the United States. METHODS: The AREDS clinical trial provides estimates of AMD progression rates and of reduction in risk of developing advanced AMD when a high-dose nutritional supplement of antioxidants and zinc is used. These results are applied to estimates of the US population at risk, to estimate the number of people who would potentially avoid advanced AMD during 5 years if those at risk were to take a supplement such as that used in AREDS. RESULTS: An estimated 8 million persons at least 55 years old in the United States have monocular or binocular intermediate AMD or monocular advanced AMD. They are considered to be at high risk for advanced AMD and are those for whom the AREDS formulation should be considered. Of these people, 1.3 million would develop advanced AMD if no treatment were given to reduce their risk. If all of these people at risk received supplements such as those used in AREDS, more than 300,000 (95% confidence interval, 158,000-487,000) of them would avoid advanced AMD and any associated vision loss during the next 5 years. CONCLUSION: If people at high risk for advanced AMD received supplements such as those suggested by AREDS results, the potential impact on public health in the United States would be considerable during the next 5 years.

Antioxidants↗
PubMed2003

Ultrasonographic biomicroscopy, Scheimpflug photography, and novel provocative tests in contralateral eyes of Chinese patients initially seen with acute angle closure.

OBJECTIVES: To compare ocular biometry of the contralateral eyes of individuals seen with acute angle closure (AAC) with eyes of population-based control subjects, and to assess novel provocative tests to study the mechanism of AAC. DESIGN: Prospective case-control study. PARTICIPANTS: Chinese persons seen as incident cases of AAC and Chinese population-based controls. METHODS: Slitlamp assessment, ultrasonographic biomicroscopy, Scheimpflug photography, and provocative testing were performed. MAIN OUTCOME MEASURES: Ocular biometric parameters including anterior chamber depth, limbal anterior chamber depth, axial length, lens thickness, and radius of corneal curvature were obtained. Ultrasonographic biomicroscopy parameters that include the angle-opening distance at 500 micro m and the angle-recess area were noted. Scheimpflug photography produced a single measure of angle width. RESULTS: Contralateral eyes of cases of AAC had shorter axial lengths, shallower anterior chamber depths, thicker lenses, and steeper radii of corneal curvature (P<.01). After adjusting for age and sex, cases had a mean adjusted axial length that was 1.2 mm shorter, an optical anterior chamber depth that was 0.63 mm shallower (24% shallower than controls), and lenses that were, on average, 0.35 mm thicker (P<.01). Furthermore, using multiple logistic regression to adjust for age and sex, patients with primary angle-closure glaucoma were 19 times as likely to have a shallower limbal anterior chamber depth (25%; 95% confidence interval, 8.3-45.2). Adjusting for age and sex, the mean angle-opening distance at 500 microm was 0.14 U less for cases, with a mean of 0.26 U in controls, making the angle-opening distance at 500 microm, on average, 54% less among cases. Scheimpflug photographs revealed an adjusted angle width of 21.6 degrees for controls and 15.1 degrees for cases (P<.05). Dynamic testing showed that the angle of control eyes tended to shallow less when going from light to dark and tended to open more when given 1 drop of pilocarpine hydrochloride. CONCLUSIONS: Contralateral eyes of individuals having an AAC attack tend to be shorter and have more crowded anterior segments than those of healthy controls. These static measures of ocular biometry indicate why some individuals are predisposed to AAC. Dynamic measures of the response to luminance changes and pilocarpine therapy indicate that differential reactions to these stimuli are also associated with an AAC attack.

Acute Disease↗
PubMed2003

Pseudoexfoliation in a rural population of southern India: the Aravind Comprehensive Eye Survey.

PURPOSE: To determine the prevalence and risk factors for pseudoexfoliation in a rural population of southern India. DESIGN: A population-based cross-sectional study of pseudoexfoliation with and without glaucoma in rural southern India. METHOD: A total of 5,150 subjects aged 40 years and older from 50 clusters representative of three southern districts of Tamil Nadu in southern India. RESULTS: All participants had a comprehensive eye examination at the base hospital, including visual acuity using logarithm of minimal angle of resolution (logMAR) illiterate E charts and refraction, slit-lamp biomicroscopy, gonioscopy, applanation tonometry, dilated fundus examinations, and automated central 24-2 full-threshold perimetry. Pseudoexfoliation (PXF) was diagnosed by the presence of typical white deposits on the anterior lens surface; additional sites included the cornea, iris, anterior vitreous face, posterior capsule, and intraocular lens in cataract-operated eyes and changes in the angle determined through gonioscopy, including increased pigmentation, PXF deposition, and PXF material within the angle. CONCLUSIONS: The prevalence (95% confidence interval) of PXF was 6.0% (5.3, 6.6). The prevalence increased with age (P <.001) and was greater in males (P =.01). Of subjects with PXF, 25.7% remained bilaterally blind after best correction; 89.3% of this bilateral blindness was the result of cataracts. The prevalence of glaucoma among subjects with PXF was 7.5%; exfoliation was present in 26.7% of those identified as primary open-angle glaucoma. On multivariate analysis, increasing age and male gender were significantly associated with PXF. Pseudoexfoliation appears to be a relatively common disorder in older individuals in southern India. Ophthalmologists in India may wish to focus on the detection of PXF, especially considering the relatively large burden of cataracts in this population, the risks for operative complications related to PXF, and the fact that PXF may be used as a marker to aid in the detectection of glaucoma.

Adult↗
PubMed2003

A prospective ultrasound biomicroscopy evaluation of changes in anterior segment morphology after laser iridotomy in Asian eyes.

PURPOSE: To prospectively quantify changes in anterior segment morphology after laser iridotomy using gonioscopy and ultrasound biomicroscopy (UBM). DESIGN: Prospective comparative observational case series. PARTICIPANTS: Fifty-five fellow eyes of patients presenting with acute primary angle closure (APAC). METHODS: The fellow eyes of patients presenting with APAC were examined with UBM, A-scan ultrasonography, and optical pachymetry at presentation and 2 weeks after sequential argon/neodymium yttrium-aluminum-garnet laser peripheral iridotomy (LPI). UBM images were analyzed using UBM Pro 2000 software. Baseline measurements were made both under standard lighting conditions and in darkness to look for changes in anterior segment findings. MAIN OUTCOME MEASURES: The degree of angle opening was measured using the angle-opening distance (AOD) at 250 and 500 microm from the scleral spur (AOD250 and AOD500, respectively) and angle recess area (ARA). RESULTS: Fifty-five Asian patients were examined; AOD250, AOD500, and ARA all significantly increased after sequential laser iridotomy (P < 0.002). Gonioscopic grading of the angle opening significantly increased in all 4 quadrants (P < 0.001). The Van Herick grade of limbal anterior chamber depth increased (P < 0.001), whereas the number of eyes classified as occludable decreased (73%-33%, P < 0.001). Anterior chamber depth did not change significantly (2.41 mm +/- 0.28 mm vs. 2.42 mm +/- 0.30 mm, P = 0.43) as measured with optical pachymetry. Increased illumination increased the angle-opening measures, but induced a different alteration in peripheral iris morphology. Illumination-induced changes were greater after iridotomy than before laser treatment. CONCLUSIONS: In Asian eyes at high risk of developing APAC, sequential LPI produced a significant widening of the anterior chamber angle without deepening the anterior chamber centrally. LPI produces changes in iris morphology that are different from those caused by an increase in illumination, indicating that different mechanisms account for angle opening under these 2 conditions.

Acute Disease↗
PubMed2003

Interventions for angle-closure glaucoma: an evidence-based update.

PURPOSE: To assess the interventions to treat acute angle closure (AAC) and primary angle closure (PAC) with or without glaucomatous optic neuropathy. CLINICAL RELEVANCE: Primary angle closure is one of the leading causes of blindness in East Asia. At present, there are few clinical guidelines on the optimal treatment of AAC or PAC in the affected or contralateral eye. METHODS: All randomized clinical trials, prospective controlled clinical trials, nonprospective controlled clinical trials, and retrospective case series with >50 cases that evaluated treatments for AAC or PAC were included. Studies published in the English language were identified from MEDLINE, PubMed, EMBASE, and the Cochrane Collaborations, as well as by a hand search of the reference lists of important articles. RESULTS: Nine randomized clinical trials and 24 nonrandomized clinical trials and large case series were evaluated. Laser peripheral iridotomy (LPI) has been found to be as effective as surgical peripheral iridectomy in randomized clinical trials of the affected and contralateral eyes of AAC or PAC patients with or without evidence of glaucoma. In another randomized clinical trial, latanoprost was found to decrease intraocular pressure (IOP) more than timolol for PAC in patients for whom LPI alone failed. CONCLUSIONS: This review suggests that LPI should be recommended for the treatment of affected and contralateral eyes of AAC patients. In patients with PAC and insufficient treatment with LPI, latanoprost eye drops may decrease IOP more than timolol. There is still insufficient evidence about other interventions for the treatment of AAC and PAC.

Acute Disease↗
PubMed2003

Glaucoma in a rural population of southern India: the Aravind comprehensive eye survey.

PURPOSE: 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.

Adult↗
PubMed2003

Angle-closure glaucoma: impact, etiology, diagnosis, and treatment.

PURPOSE OF REVIEW: Recent studies underscore the importance of angle-closure glaucoma (ACG) as a cause of world blindness. A major contribution in assessing the true impact of this disease has been an article estimating the number of persons with occludable angles, angle closure, and blindness from ACG in China as 28.2 million, 9.1 million, and 1.7 million, respectively. Although these numbers are based on data from Singapore and Mongolia, which may be applied to China only with caution, they emphasize the blinding potential of ACG, which is three times as likely to be associated with blindness as open-angle glaucoma (OAG). RECENT FINDINGS: Recent reports in the Chinese literature on ACG prevalence suffer from definitional problems that would appear to lead to systematic overestimates of ACG prevalence and underestimates of OAG prevalence. Nonetheless, data from studies by Chinese investigators further emphasize the strong association between ACG and blindness, with fully 16% of subjects with ACG blind in one report-a far higher proportion than for OAG in China and elsewhere. The importance of topiramate as a cause of secondary angle closure has recently been understood, in part, because of a series of 19 such cases reported by investigators at the Food and Drug Administration. SUMMARY: Angle closure in this setting appears to be caused by uveal effusion and anterior rotation of the ciliary body with resultant closure of the angle. The condition is not always responsive to laser iridectomy, and elimination of the causative agent appears to be critical. Ultrasonic biomicroscopy is a potential new diagnostic modality for ACG, allowing the measurement of novel parameters, such as the angle opening distance (AOD) at 500 microm (AOD 500). The efficacy of such parameters in improving screening for ACG can only be established by prospective studies of potentially at-risk eyes. A number of novel treatments for AC and angle closure have recently been proposed, including cataract extraction, paracentesis, and argon laser iridoplasty. As with proposed new diagnostic modalities, the efficacy of these treatments remains to be demonstrated with prospective studies, ideally organized in a controlled, randomized fashion.

Blindness↗