Prevalence Of Legal Blindness Research Articles

Epidemiology and Course of Disease in Childhood Uveitis

To describe the disease characteristics and visual outcome of pediatric uveitis. Retrospective, longitudinal observation. Five hundred twenty-seven pediatric uveitis patients from the National Eye Institute, University of Illinois, Chicago, and Oregon Health Sciences University. Retrospective chart review. Demographics, uveitis disease characteristics, complications, treatments, and visual outcomes were determined at baseline and at 1-, 3-, 5-, and 10-year time points. The patient population was 54% female; 62.4% white, 12.5% black, 2.7% Asian, 2.1% multiracial, and 14.61% Hispanic. Median age at diagnosis was 9.4 years. The leading diagnoses were idiopathic uveitis (28.8%), juvenile idiopathic arthritis-associated uveitis (20.9%), and pars planitis (17.1%). Insidious onset (58%) and persistent duration (75.3%) were most common. Anterior uveitis was predominant (44.6%). Complications were frequent, and cystoid macular edema (odds ratio [OR] 2.94; P = 0.006) and hypotony (OR, 4.54; P = 0.026) had the most significant visual impact. Ocular surgery was performed in 18.9% of patients. The prevalence of legal blindness was 9.23% at baseline, 6.52% at 1 year, 3.17% at 3 years, 15.15% at 5 years, and 7.69% at 10 years. Posterior uveitis and panuveitis had more severe vision loss. Hispanic ethnicity was associated with a higher prevalence of infectious uveitis and vision loss at baseline. The rate and spectrum of vision threatening complications of pediatric uveitis are significant. Prospective studies using standard outcome measures and including diverse populations are needed to identify children most at risk.

Prevalence and Causes of Blindness & Low Vision; Before and Five Years After ‘VISION 2020’ Initiatives in Oman: A Review

Background: A prevalence survey of blindness and low vision was conducted in Oman in 2005. Here, we present the prevalence and determinants of blindness and low vision among the population ≥ 40 years of age. The results are then compared with those of the survey in 1997 and the changes following the ‘VISION 2020’ initiatives are assessed. Methods: The survey covered 24 randomly selected clusters (75 houses in each). Teams assessed the distance vision of subjects while wearing glasses. The ophthalmologists examined the anterior segment and fundus to determine the causes of disability. The visual field was tested in those suspected of glaucoma. The prevalence rates of blindness (< 3/60 on presentation), legal blindness (< 6/60) and low vision (< 6/18) were calculated. The data from the 1997 survey was then analyzed to obtain similar rates in the population ≥ 40 years of age. Results: The prevalence of blindness was 8.25% (95% CI 7.14–9.36) in the ≥ 40 year-old population in 2005. The rate would be 6.95% (95% CI 5.92–7.98) if blindness were defined as vision with best possible correction. The prevalence of legal blindness and low vision were 12% and 45.12%, respectively. In the 1997 survey, the prevalence of blindness in same age group was 7.23% (95% CI 5.91–8.55). Between the two surveys, the prevalence of blindness due to corneal pathology declined from 1.9% to 1.1% but that of blindness due to unoperated cataract increased from 1.8% to 2.3%. Conclusions: The rate of disability has declined but the number of blind people has increased in Oman. The causes of blindness have changed from communicable/avoidable eye diseases to non-curable/chronic eye diseases, and the number with visual disabilities has increased. An increasing number of operations for cataract and improvements in the care for glaucoma and diabetic retinopathy are recommended.

Is Homelessness a Risk Factor for Eye Disease?

Background: There is general agreement on the presence of a correlation between poverty and impaired health. However, only scarce data are available on whether this also applies to the incidence of eye disease. The present study was carried out to evaluate the prevalence of ocular disease in homeless people in Germany. Methods: 107 homeless people (97 male, 10 female; mean age 49 years, range 18–81 years) treated in specialised social service institutions were investigated prospectively according to a standardised ophthalmological screening protocol. This comprised visual acuity, assessment of pupillary light reaction, intra-ocular pressure, slit lamp examination as well as funduscopy. Results: The median best-corrected visual acuity of all 213 eyes examined was 0.8 (range: no light perception to 1.25). 74 eyes of a subgroup of 50 patients showed one or more of the following disorders: 32% of the patients suffered from external eye disease, 8% exhibited a cataract associated with a visual acuity of 0.63 or below. 6% of the patients had optic nerve atrophy, and 4% suffered from amblyopia. Diabetic retinopathy as well as age-related macular degeneration were detected in 2%, while anophthalmos, lid malposition and traumatic choroidal rupture were noted in 1% of patients. The median visual acuity measured in these 74 eyes was 0.5 (range: no light perception to 1.25), which differs significantly from the acuity of 0.8 in the entire study population (p < 0.001). The prevalence of legal blindness according to WHO criteria was 2%. Conclusions: The present study revealed an unexpectedly high prevalence of optic nerve atrophy in homeless people. The prevalence for cataract and legal blindness was slightly higher than in representative epidemiological investigations. Thus, homelessness seems to be correlated with an increased ocular morbidity. As best-corrected visual acuity differed significantly between eyes with and those without eye disease, the assessment of this parameter may serve as a cost-effective first-stage screening method.

Cause-specific prevalence of bilateral visual impairment in Victoria, Australia

To study the cause-specific prevalence of eye diseases causing bilateral visual impairment in Australian adults. Two-site, population-based cross-sectional study. Participants were aged 40 years and older and resident in their homes at the time of recruitment for the study. The study was conducted during 1992 through 1996. The study uses a cluster stratified random sample of 4744 participants from two cohorts, urban, and rural Victoria. Participants completed a standardized interview and eye examination, including presenting and best-corrected visual acuity, visual fields, and dilated ocular examination. The major cause of vision loss was identified for all participants found to be visually impaired. Population-based prevalence estimates are weighted to reflect the age and gender distribution of the two cohorts in Victoria. Visual impairment was defined by four levels of severity on the basis of best-corrected visual acuity or visual field: <6/18 > or =6/60 and/or <20 degrees > or =10 degrees radius field, moderate vision impairment; severe vision impairment, <6/60 > or =3/60 and/or <10 degrees > or =5 degrees radius field; and profound vision impairment <3/60 and/or <5 degrees radius field. In addition, less-than-legal driving vision, <6/12 > or =6/18, and/or homonymous hemianopia were defined as mild vision impairment. In Australia, legal blindness includes severe and profound vision impairment. The population-weighted prevalence of diseases causing less-than-legal driving or worse impairment in the better eye was 42.48/1000 (95% confidence interval [CI], 30.11, 54.86). Uncorrected refractive error was the most frequent cause of bilateral vision impairment, 24.68/1000 (95% CI, 16.12, 33.25), followed by age-related macular degeneration (AMD), 3.86/1000 (95% CI, 2.17, 5.55); other retinal diseases, 2.91/1000 (95% CI, 0.74, 5.08); other disorders, 2.80/1000 (95% CI, 1.17, 4.43); cataract, 2.57/1000 (95% CI, 1.38, 3.76); glaucoma, 2.32/1000 (95% CI, 0.72, 3.92); neuro-ophthalmic disorders, 1.80/1000 (95% CI, 0, 4.11); and diabetic retinopathy, 1.53/1000 (95% CI, 0.71, 2.36). The prevalence of legal blindness was 5.30/1000 (95% CI, 3.24, 7.36). Although not significantly different, the causes of legal blindness were uncorrected refractive errors, AMD, glaucoma, other retinal conditions, and other diseases. Significant reduction of visual impairment may be attained with the application of current knowledge in refractive errors, diabetes mellitus, cataract, and glaucoma. Although easily preventable, uncorrected refractive error remains a major cause of vision impairment.

Visual Impairments in Elderly People under Everyday Viewing Conditions

This study measured the conventional high-contrast visual acuity, low-contrast visual acuity, low-contrast, low-luminance (SKILL) acuity, contrast sensitivity, disability glare sensitivity, glare recovery, stereo acuity, and visual fields of 900 elderly persons, including 450 aged 75–100. Although the prevalence of legal blindness and low vision were relatively low under conventional conditions, there were dramatic increases in these two conditions under low luminance or glare conditions. The practical implications of these findings are discussed.

Blindness Caused by Diabetes— Massachusetts, 1987-1994

Diabetes, the leading cause of new blindness among U.S. adults aged 20-74 years, accounts for approximately 8% of cases of legal blindness and 12% of all new cases of blindness in the United States each year. One of the national health objectives for the year 2000 is to decrease by 50% the incidence of blindness caused by diabetes (objective 17.10). However, surveillance for blindness among persons with diabetes has not been conducted nationally, and national prevalence estimates of blindness caused by diabetes have been based on state data from the register of the Massachusetts Commission for the Blind (MCB). To characterize recent trends, data on legal blindness caused by diabetes among adults with diabetes in Massachusetts were examined for 1987-1994. This report summarizes the results of that analysis, which indicate that in Massachusetts, the overall incidence and prevalence of legal blindness caused by diabetes did not decrease, despite the availability of methods to prevent vision loss.

Legal blindness among 10-year-old children in Metropolitan Atlanta: prevalence, 1985 to 1987.

The prevalence of legal blindness in 10-year-olds in metropolitan Atlanta was 6.8 per 10,000 during 1985 to 1987. The prevalence was 8.8 per 10,000 in Black boys, 8.6 per 10,000 in White boys, 6.7 per 10,000 in White girls, and 1.8 per 10,000 in Black girls. Retinopathy of prematurity was the most common known cause (1.0 per 10,000). Of the 61 cases, 40 had other disabilities, including 14 with mental retardation, cerebral palsy, and epilepsy. The low prevalence among Black girls and the frequent occurrence of blindness with other disabilities are noteworthy.

BLINDNESS IN ICELAND

In a special survey 419 legally blind persons (corrected visual acuity 6/60 or less) were traced throughout the whole counntry at the end of the year 1979. The overall prevalence of legal blindness is 185.1 per 100000 population. By using the locomotor vision criteria (3/60) the number is 272 and the overall rate 120 per 100000. Two thirds of the legally blind and one third have no useful vision. The prevalence of legal blindness is highest in the oldest age groups and 50% of the total are over 80 years old. The most common causes of legal blindness are senile macular degeneration (39.6%), prenatal influence (19.3%), open angle glaucoma (17.7%). The blindness rate has decreased a great deal in the past three decades. This is due to a decreased incidence in glaucoma blindness. For years there had been no organized registration of the blind in Iceland and the number of visually handicapped people were therefore unknown. A study of legally blind and partially seeing children was done in 1978 (Halldórsson &amp; Björnsson 1980).