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Objective To determine the prevalence, etiologies, and risk factors of blindness and visual impairment among persons age 40 years and older residing in an urban West African location. Design Population-based cross-sectional study. Participants Five thousand six hundred and three participants residing in Tema, Ghana. Methods Proportionate random cluster sampling was used to select participants age 40 and over living in the city of Tema. Presenting distance visual acuity was measured at 4 and 1 meters using a reduced Logarithm of the Minimum Angle of Resolution (logMAR) tumbling E chart and then with trial frame based on autorefraction. A screening examination was performed in the field on all participants. Complete clinical examination by an ophthalmologist was performed on participants with best corrected visual acuity < 20/40 or failure of any screening test. Main Outcome Measures Age- and gender-specific prevalence, causes, and risk factors for blindness (visual acuity in the better eye of < 20/400, World Health Organization definition) and visual impairment (visual acuity in the better eye of < 20/40). Results Six thousand eight hundred and six eligible participants were identified of which 5603 (82.3%) participated in the study. The mean age (±standard deviation) of participants was 52.7±10.9. The prevalence of visual impairment was 17.1% and blindness was 1.2%. After refraction and spectacle correction, the prevalence of visual impairment and blindness decreased to 6.7% and 0.75% respectively, suggesting that refractive error is the major correctable etiology of visual impairment and blindness in this population. Of 65 subjects having visual acuity < 20/400, 22 (34%) were correctable with refraction, 21 to the level of visual impairment, and one to normal. The remaining 43 (66%) had underlying pathology (19 cataract, 9 glaucoma, 3 non-glaucomatous optic neuropathy, 3 corneal opacities, 3 retinal disease, 5 undetermined) that prevented refractive correction. Increased age was a significant risk factor for blindness and visual impairment. Conclusions There is a high prevalence of blindness and visual impairment among those aged ≥40 years in Tema, Ghana, West Africa. Refractive error is a major cause of blindness and visual impairment in this population, followed by cataract, glaucoma, and corneal disease.

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Purpose To compare the results of Glaucoma Progression Analysis (GPA, Carl Zeiss Meditec, Dublin, CA) to subjective expert consensus in the detection of glaucomatous visual field progression. Design Retrospective, observational case series. Participants 100 eyes of 83 glaucoma patients. Methods Five serial Humphrey visual fields from 100 eyes of 83 glaucoma patients were evaluated by five masked glaucoma subspecialists for determination of progression. Four months later, with a randomly reordered patient sequence, the same visual field series were re-evaluated by the same graders, at which time they had access to the Glaucoma Progression Analysis (GPA) printout. Main Outcome Measures The level of agreement between majority expert consensus and GPA, both before and after access to GPA data, was assessed using kappa statistics. Results On initial review and on re-evaluation with access to the GPA printout, the level of agreement between majority expert consensus and GPA was fair (kappa = 0.52, 95% confidence interval [CI] = 0.35 – 0.69 and 0.62, 95% CI = 0.46 – 0.78, respectively). Expert consensus was more likely to classify a series of fields as showing progression than was GPA (p ≤ 0.002). There was good agreement between expert consensus on initial review and reevaluation 4 months later (kappa = 0.77, 95% CI = 0.65 – 0.90). Conclusions The level of agreement between majority expert consensus of subjective determination of visual field progression and GPA is fair. In cases of disagreement with GPA, the expert consensus classification was usually progression. Access to the results of GPA did not significantly change the level of agreement between expert consensus and the GPA result; however, expert consensus did change in 11 of 100 cases.

IMPORTANCE Laser trabeculoplasty (LTP) is routinely used to treat open-angle glaucoma; hence, understanding variations in its use over time and region is important. OBJECTIVE To determine trends over time and the regional variation in the performance of LTP. DESIGN, SETTING, AND PARTICIPANTS Database analysis of a 5% random sample of all Medicare beneficiaries 65 years or older with continuous Part B (medical insurance) coverage and no enrollment in a health maintenance organization for each year from 2002 through 2009.INTERVENTIONS We counted unique claims with a Current Procedural Terminology code of 65855 (LTP) submitted by ophthalmologists, optometrists, ambulatory surgery centers, or outpatient hospitals by region for each year. We examined trends over time and regional variation in LTP rates in 9 large geographic regions. MAIN OUTCOMES AND MEASURES Rate of LTP per 10 000 Medicare beneficiary person-years and per 10 000 diagnosed open-angle glaucoma (OAG) person-years.