Low vision and blindness in adults in Gurage Zone,central Ethiopia

AIM: To determine the magnitude and causes of low vision and blindness in the Gurage zone, central Ethiopia. METHODS: A cross sectional study using a multistage cluster sampling technique was used to identify the study subjects. Visual acuity was recorded for all adults 40 years and older. Subjects who had a visual acuity of <6/18 were examined by an ophthalmologist to determine the cause of low vision or blindness. RESULTS: From the enumerated population, 2693 (90.8%) were examined. The prevalence of blindness (<3/60 better eye presenting vision) was 7.9% (95% CI 6.9 to 8.9) and of low vision (6/24-3/60 better eye presenting vision) was 12.1% (95% CI 10.9 to 13.3). Monocular blindness was recorded in 16.3% of the population. Blindness and low vision increased with age. The odds of low vision and blindness in women were 1.8 times that of the men. The leading causes of blindness were cataract (46.1%), trachoma (22.9%), and glaucoma (7.6%). While the prevalence of vision reducing cataract increased with age, the prevalence of trachoma related vision loss did not increase with age, suggesting that trichiasis related vision loss in this population might not be cumulative. CONCLUSION: The magnitude of low vision and blindness is high in this zone and requires urgent intervention, particularly for women. Further investigation of the pattern of vision loss, particularly as a result of trachomatous trichiasis, is warranted.     

Blindness and Low Vision in Cape Verde Islands: Results of a National Eye Survey

Aims: Prior to establishing a national prevention of blindness program a population based survey was conducted in Cape Verde Islands in1998. The objectives of the survey were to estimate the overall and age-specific prevalence of blindness and low vision, to identify the main disorders causing blindness and low vision, and to estimate the population need for basic eye care services. Methods: A two-level cluster random sampling procedure was used, selecting 30 clusters from the nine inhabited islands and 3,803 persons of all ages were included in the sample. Results: 3,374 persons were examined (coverage 88.7%). The prevalence of bilateral blindness (visual acuity in the better eye less than 3/60) was 0.8% (95% confidence interval [CI] 0.5–1.1), of bilateral low vision (6/18 to 3/60 in the better eye) 1.7% (95% CI: 1.3–2.2) and of monocular blindness 1.5% (95% CI: 1.2–2.0). The major causes of blindness were age related cataract and glaucoma (57.7% and 15.4%, respectively, of blind people recruited). The major causes of bilateral low vision were cataract, refractive errors, and macular disorders (46.2%, 26.8%, and 8.9%, respectively, of persons with low vision). Nontrachomatous corneal opacities accounted for 7.7% of bilateral and for 11.5% of monocular blindness. Vascular retinopathy was responsible for 7.7% of bilateral and for 9.6% of monocular blindness. Trachoma is not a public health problem as only 2.3% of children less than 10 years of age were suffering from active trachoma. Palpebral or limbal vernal conjunctivitis were encountered in 4.5% of persons under 25. Conclusion: More than half of the visual impairments are treatable by provision of cataract surgery and cataract has been indicated as a priority target in the recently designed National Blindness Program of the Cape Verde Republic. Pathologic conditions such as diabetes are emerging as serious burden for ageing populations and account for most of the retinal vascular disease.     

Blindness and low vision in Cape Verde Islands: results of a national eye survey

AIMS: Prior to establishing a national prevention of blindness program a population based survey was conducted in Cape Verde Islands in1998. The objectives of the survey were to estimate the overall and age-specific prevalence of blindness and low vision, to identify the main disorders causing blindness and low vision, and to estimate the population need for basic eye care services. METHODS: A two-level cluster random sampling procedure was used, selecting 30 clusters from the nine inhabited islands and 3,803 persons of all ages were included in the sample. RESULTS: 3,374 persons were examined (coverage 88.7%). The prevalence of bilateral blindness (visual acuity in the better eye less than 3/60) was 0.8% (95% confidence interval [CI] 0.5-1.1), of bilateral low vision (6/18 to 3/60 in the better eye) 1.7% (95% CI: 1.3-2.2) and of monocular blindness 1.5% (95% CI: 1.2-2.0). The major causes of blindness were age related cataract and glaucoma (57.7% and 15.4%, respectively, of blind people recruited). The major causes of bilateral low vision were cataract, refractive errors, and macular disorders (46.2%, 26.8%, and 8.9%, respectively, of persons with low vision). Nontrachomatous corneal opacities accounted for 7.7% of bilateral and for 11.5% of monocular blindness. Vascular retinopathy was responsible for 7.7% of bilateral and for 9.6% of monocular blindness. Trachoma is not a public health problem as only 2.3% of children less than 10 years of age were suffering from active trachoma. Palpebral or limbal vernal conjunctivitis were encountered in 4.5% of persons under 25. CONCLUSION: More than half of the visual impairments are treatable by provision of cataract surgery and cataract has been indicated as a priority target in the recently designed National Blindness Program of the Cape Verde Republic. Pathologic conditions such as diabetes are emerging as serious burden for ageing populations and account for most of the retinal vascular disease.     

西藏自治区墨脱县人群盲和低视力现况调查

目的探讨与了解西藏自治区墨脱县人群盲与低视力的流行病学变化情况。方法以村为基础,采用随机整群抽样原则,抽取6个行政村作为调查地点。采用世界卫生组织制定的盲与低视力标准,对全县按2．05％抽样比例抽取样本进行盲与低视力的流行病学调查。结果检录821人中,受检人数为735人,受检率为89．52％。双眼盲19人,盲率为2．59％（男性1．72％,女性3．40％）;双眼低视力32人,低视力患病率为4．35％（男性4．02％,女性4．67％）。≥40岁盲及低视力患者的患病率明显增高。致盲的眼病依次为白内障（42．11％）、角膜病（21．05％）及青光眼（15．79％）。结论西藏自治区墨脱县人群中盲和致低视力的眼病以白内障居首位,因此手术治疗白内障仍是今后防盲治盲工作的首要任务。     

Prevalence and Causes of Blindness and Low Vision Revisited after 5 years of Eye Care in Timor-Leste

Purpose: To estimate the 2010 prevalence and causes of blindness and low vision among Timor-Leste adults aged ≥40 years, and compare these to the results of a survey conducted 5 years previously.

Method: A population-based cross-sectional survey used multistage cluster random sampling proportionate to size to identify 50 clusters of 45 people each. Cause of vision loss was determined for each eye with presenting visual acuity worse than 6/18.

Results: A participation rate of 89.5% (n?=?2014) was achieved. The gender-age-domicile adjusted prevalence was 7.7% (95% confidence interval [CI] 6.5, 8.8) for 6/60, and 3.6% (95% CI 2.7, 4.4) for 3/60 blindness (better eye presenting vision worse than 6/60 and 3/60, respectively) among Timorese aged ≥40 years. Cataract caused most blindness (69.3% at 6/60). The population prevalence of low vision (better eye presenting vision of 6/60 or better, but worse than 6/18) was 13.6% (95%CI 12.1, 15.1), most caused by uncorrected refractive error (57.4%) or cataract (39.5%). The prevalence and causes of blindness were unchanged compared with 5 years earlier, but low vision was less common.

Conclusion: Unusually for a developing country, Timor-Leste has initiated a cycle of evidence-based eye care in which, although with limitations, population data are periodically available for monitoring and planning.     

Gender inequality in vision loss and eye diseases: Evidence from the Sultanate of Oman

Purpose:

The data from surveys of vision loss and monitoring of services were used to assess changes in gender inequality in Oman.

Study Design:

Retrospective review of data collection instruments.

Materials and Method:

The data sets of 12 years between 1996 and 2007 were abstracted to assess the gender equality for vision loss, eye disease prevalence, and service use. They included two surveys (1996 and 2005), Health Information from eye units (1998 and 2007), and eye screening in schools.

Results:

In 1996, the prevalence of bilateral blindness in ≥ 40 years of age was higher in females [Odd''s Ratio (OR) = 0.36 (95% Confidence Interval (CI) 0.24 – 0.53)]. Gender differences in the prevalence of cataract [OR = 0.82 (95% CI 0.63 – 1.03)] were not significant while trachomatous trichaisis (TT) was less in males [OR = 0.33 (95% CI 0.22-0.48)]. In 2005, gender differences in the prevalence of bilateral blindness [OR = 0.97 (95% CI 0.71 – 1.34)] and TT [OR = 0.66 (95% CI 0.42- 1.04)] were not statistically significant. But males were associated with higher prevalence of cataract [OR = 1.26 (95% CI 1.00 – 1.59)]. Surgery rates for cataract, glaucoma and TT were not different by gender. More male compared to female patients with diabetic retinopathy were treated. Myopia was significantly higher in girls. Compliance of spectacle wear was higher in girls.

Conclusions:

Gender inequality for eye care seems to have reduced in the last 10 years in Oman. However, apart from TT and glaucoma patients the difference in service utilization by gender was not statistically significant.     

Prevalence and causes of blindness and low vision in Timor-Leste

AIM: To estimate the prevalence and causes of blindness and low vision in people aged > or = 40 years in Timor-Leste. METHOD: A population-based cross-sectional survey using multistage cluster random sampling to identify 50 clusters of 30 people. A cause of vision loss was determined for each eye presenting with visual acuity worse than 6/18. RESULTS: Of 1470 people enumerated, 1414 (96.2%) were examined. The age, gender and domicile-adjusted prevalence of functional blindness (presenting vision worse than 6/60 in the better eye) was 7.4% (95% CI 6.1 to 8.8), and for blindness at 3/60 was 4.1% (95% CI 3.1 to 5.1). The adjusted prevalence for low vision (better eye presenting vision of 6/60 or better, but worse than 6/18) was 17.7% (95% CI 15.7 to 19.7). Gender was not a risk factor for blindness or low vision, but increasing age, illiteracy, subsistence farming, unemployment and rural domicile were risk factors for both. Cataract was the commonest cause of blindness (72.9%) and an important cause of low vision (17.8%). Uncorrected refractive error caused 81.3% of low vision. CONCLUSION: Strategies that make good-quality cataract and refractive error services available, affordable and accessible, especially in rural areas, will have the greatest impact on vision impairment.     

Prevalence and causes of low vision and blindness in an urban population: The Chennai Glaucoma Study

Aim:

To evaluate the prevalence and causes of low vision and blindness in an urban south Indian population.

Settings and Design:

Population-based cross-sectional study. Exactly 3850 subjects aged 40 years and above from Chennai city were examined at a dedicated facility in the base hospital.

Materials and Methods:

All subjects had a complete ophthalmic examination that included best-corrected visual acuity. Low vision and blindness were defined using World Health Organization (WHO) criteria. The influence of age, gender, literacy, and occupation was assessed using multiple logistic regression.

Statistical Analysis:

Chi-square test, t-test, and multivariate analysis were used.

Results:

Of the 4800 enumerated subjects, 3850 subjects (1710 males, 2140 females) were examined (response rate, 80.2%). The prevalence of blindness was 0.85% (95% CI 0.6–1.1%) and was positively associated with age and illiteracy. Cataract was the leading cause (57.6%) and glaucoma was the second cause (16.7%) for blindness. The prevalence of low vision was 2.9% (95% CI 2.4–3.4%) and visual impairment (blindness + low vision) was 3.8% (95% CI 3.2–4.4%). The primary causes for low vision were refractive errors (68%) and cataract (22%).

Conclusions:

In this urban population based study, cataract was the leading cause for blindness and refractive error was the main reason for low vision.     

Causes of low vision and blindness in rural Indonesia

AIM: To determine the prevalence rates and major contributing causes of low vision and blindness in adults in a rural setting in Indonesia METHODS: A population based prevalence survey of adults 21 years or older (n=989) was conducted in five rural villages and one provincial town in Sumatra, Indonesia. One stage household cluster sampling procedure was employed where 100 households were randomly selected from each village or town. Bilateral low vision was defined as habitual VA (measured using tumbling "E" logMAR charts) in the better eye worse than 6/18 and 3/60 or better, based on the WHO criteria. Bilateral blindness was defined as habitual VA worse than 3/60 in the better eye. The anterior segment and lens of subjects with low vision or blindness (both unilateral and bilateral) (n=66) were examined using a portable slit lamp and fundus examination was performed using indirect ophthalmoscopy. RESULTS: The overall age adjusted (adjusted to the 1990 Indonesia census population) prevalence rate of bilateral low vision was 5.8% (95% confidence interval (CI) 4.2 to 7.4) and bilateral blindness was 2.2% (95% CI 1.1 to 3.2). The rates of low vision and blindness increased with age. The major contributing causes for bilateral low vision were cataract (61.3%), uncorrected refractive error (12.9%), and amblyopia (12.9%), and the major cause of bilateral blindness was cataract (62.5%). The major causes of unilateral low vision were cataract (48.0%) and uncorrected refractive error (12.0%), and major causes of unilateral blindness were amblyopia (50.0%) and trauma (50.0%). CONCLUSIONS: The rates of habitual low vision and blindness in provincial Sumatra, Indonesia, are similar to other developing rural countries in Asia. Blindness is largely preventable, as the major contributing causes (cataract and uncorrected refractive error) are amenable to treatment.     

Prevalence and Causes of Blindness,Low Vision and Status of Cataract in 50 Years and Older Citizen of Qatar—A Community Based Survey

Background: Rapid Assessment for the Avoidable Blindness (RAAB) was conducted in Qatar during 2009. We present the prevalence and determinants of visual disabilities and status of cataract among citizens aged 50 years and older.

Methods: Residents of randomly selected houses and clusters participated in the survey. Opticians noted the presenting and the best corrected vision of participants from 49 clusters. Ophthalmologists examined participants with additional instruments like bio-microscope, digital camera, auto-perimeter and auto-refractor in a mobile van. World Health Organization recommended principal cause of blindness (Visual acuity [VA]?<?3/60 in better eye), Severe visual impairment (SVI) (<6/60), low vision (VA?<?6/18) and unilateral blindness (VA?<?3/60) were designated. Persons with VA?<?6/18 and cataract were interviewed to calculate coverage and barriers for cataract surgeries. Age sex adjusted prevalence of visual disabilities and their 95% Confidence Intervals (CI) were estimated.

Results: We examined 2,433 (97.3%) participants. The age sex adjusted prevalence of bilateral blindness was 1.28% [95% CI 1.22–1.35], SVI (1.67%), low vision (3.66%) and unilateral blindness (3.61%) in 50 years and older population. Female and older age groups were significant risk factors of visual disabilities. Cataract and glaucoma were the main causes of visual disabilities. The coverage of cataract services was 68.2%. Believing that cataract as an aging process (25) and adequate vision in the fellow eye (15) were the reasons for delay in surgery.

Conclusions: To reduce avoidable blindness, un-operated cataract should be addressed. Primary and secondary eye care systems should be strengthened to improve the care of blinding eye diseases in Qatar.     

The prevalence and causes of blindness in the Sultanate of Oman: the Oman Eye Study (OES)

AIMS: To estimate the magnitude and the causes of blindness through a community based nationwide survey in Oman. This was conducted in 1996-7. METHODS: A stratified cluster random sampling procedure was used to select 12 400 people. The WHO/PBD standardised survey methodology was used, with suitable adaptation. The major causes of blindness were identified among those found blind. RESULTS: A total of 11 417 people were examined (response rate 91.8%) The prevalence of blindness in the Omani population was estimated to be 1.1% (95% CI 0.9 to 1.3), blindness being defined according to the WHO Tenth Revision of the International Classification of Diseases. Prevalence of blindness was clearly related to increasing age, with estimates of 0.08% for the 0-14 age group, 0.1% for the 15-39 age group, 2.3% for the 40-59 age group, and 16.8% for the group aged 60 +. There was a statistically significant difference between the prevalence in females (1.4%) and males (0.8%). The northern and central regions had a higher prevalence of blindness (1.3% to 3%). The major causes of blindness were unoperated cataract (30.5%), trachomatous corneal opacities (23.7%), and glaucoma (11.5%) CONCLUSIONS: Despite an active eye healthcare programme, blindness due to cataract and trachoma remains a public health problem of great concern in several regions of the sultanate. These results highlight the need, when planning effective intervention strategies, to target the eye healthcare programme to the ageing population, with special emphasis on women.     

Four-year incidence of visual impairment: Barbados Incidence Study of Eye Diseases

OBJECTIVE: To describe the 4-year incidence of visual impairment and causes of blindness among black participants of the Barbados Eye Studies. DESIGN: Population-based incidence study. SETTING AND PARTICIPANTS: The Barbados Incidence Study of Eye Diseases (BISED) followed the cohort of the Barbados Eye Study (BES), a prevalence study based on a simple random sample of Barbadians 40 to 84 years of age. BISED included 3193 black participants from the original cohort (85% of those eligible). MAIN OUTCOME MEASURES: Best-corrected visual acuity (Ferris-Bailey chart) at baseline and follow-up was measured according to a modified Early Treatment of Diabetic Retinopathy Study protocol. By use of World Health Organization (WHO) criteria, low vision and blindness for an individual were defined as visual acuity (VA) <6/18 to 6/120 and <6/120, respectively, in the better eye. By commonly used US criteria, low vision and blindness were defined as VA < or = 20/40 and < or = 20/200, respectively. Vision loss was defined as a doubling of the visual angle (i.e., decrease of 15 letters or more read correctly between baseline and follow-up examinations). Progression was defined as vision loss among those with low vision at baseline. RESULTS: On the basis of WHO criteria, the overall 4-year incidence was 3.6% (95% confidence interval [CI], 3.0%-4.4%) for low vision and 0.6% (95% CI, 0.4%-1.0%) for blindness. Incidence rates were higher using US criteria: 5.3% (95 % CI, 4.5%-6.2%) and 1.5% (95% CI, 1.1%-2.0%), respectively, reaching 21.5% and 7.3% for persons aged 70 years or older at baseline. One tenth of the cohort had vision loss, and 28.6% of those with low vision progressed. About one half of incident blindness was due to age-related cataract. Nearly one fifth was caused by open-angle glaucoma (OAG) alone or combined with cataract, and approximately 10% was caused by diabetic retinopathy (DR). CONCLUSIONS: The incidence of visual impairment was high in this Afro-Caribbean population, particularly in older age groups, indicating the public health significance of visual loss for this and similar black populations. Cataract, OAG, and DR were among the leading causes of incident blindness, paralleling their high prevalence in this population.     

Cataract prevalence, cataract surgical coverage and its contribution to the reduction of visual disability in Oman

AIM: To estimate the magnitude and determinants of cataract prevalence and cataract surgical coverage and to evaluate their role in visual disability in Oman. METHODS: A cross-sectional study was conducted on 11,413 subjects in Oman in 1997. The presence and stage of cataract was noted on the basis of the history and an examination. The patient's phakic, pseudophakic or aphakic status and visual status were determined. The prevalence of cataract and the cataract surgical coverage were estimated. A causal relation was assumed between a backlog of cataract and age, gender and area of residence. The Attributable Risk (AR) and Population Attributable Risk (PAR) for these factors were estimated. RESULTS: The prevalence of cataract was 29.3/1000 (95% CI: 27.76 to 30.84). This was 4.97/1000 (95% CI: 3.68 to 6.26) for blinding cataract (vision < 3/60). The cataract surgery services covered 70.18% (95% CI: 69.52 to 70.84) of the blinding cataracts and 28.76% (95% CI: 28.11 to 29.41) of all cataracts. The AR and PAR of female gender in the cataract backlog were 35.5% and 1.06%, respectively. The AR and PAR of the residents of 'Group B' regions were 40.5% and 1.26%, respectively. The AR and PAR of subjects "less than 60 years old' were 55.6% and 1.66%, respectively. If the gaps in cataract surgery due to gender, regions and age groups were to be filled, the prevalence of cataract could be reduced by 1.06%, 1.21% and 1.66%, respectively. CONCLUSION: The health program should identify and address the barriers to cataract surgery among identified high-risk groups.     

Prevalence and causes of visual impairment and blindness in Sistan-va-Baluchestan Province, Iran: Zahedan Eye Study

AIM: To determine the prevalence and causes of visual impairment and blindness in the Sistan-va-Baluchestan Province of Iran. METHODS: A population-based cross-sectional study with a multistage cluster sampling technique was used to identify the study subjects. Visual acuity (VA) was defined for all participants aged >or=10 years. Participants with a VA of <20/60 were examined by an ophthalmologist to determine the causes of low vision or blindness. RESULTS: 5446 (84.0%) of the invited people were examined. The prevalence of visual impairment (VA <20/60) was 6.81% (95% CI 5.91% to 7.71%) and of bilateral blindness (VA <3/60) was 0.79% (95% CI 0.50% to 1.08%). Visual impairment increased with age and illiteracy. Bilateral blindness doubled in women aged >40 years. The causes of visual impairment and blindness were cataract (37.7%), corneal opacity (15.0%), amblyopia (15.0%), glaucoma (5.7%) and hyperopia (5.0%). 39.5% of the visual impairment cases were potentially curable. CONCLUSION: The estimated magnitude of visual impairment and blindness was much higher than our expectations. Further investigation of the pattern of vision loss in women and children, particularly as a result of trachoma and amblyopia, is warranted. Implementation of measures to treat curable cases of the study population can improve the situation in the region dramatically.     

Blindness and eye disease in Cambodia

PURPOSE: To assess the prevalence and etiology of blindness and low vision and to assess the prevalence of common eye diseases in central Cambodia. METHODS: In this cross-sectional, population-based study, 6,558 residents of Kandal Province, Cambodia were registered, and 5,803 (88.5%) were interviewed and examined. This house-to-house survey was conducted by a team consisting of a senior ophthalmologist, a Cambodian eye doctor, and eight Cambodian eyecare workers. RESULTS: The prevalence of bilateral blindness (visual acuity <3/60) is 1.1% (95% confidence interval [CI], 0.9-1.4), and an additional 4.4% (95% CI, 3.9-5.0) have low vision (visual acuity < 6/18, > or =3/60 in the better eye). The major causes of bilateral blindness are cataract (67.4%), phthisis (6.1%), uncorrected refractive error (6.1%), corneal scar (5.3%), uncorrected aphakia (3.0%), trachoma corneal scar (3.0%), optic atrophy (3.0%), and others (6.1%). The major causes of low vision are uncorrected refractive error (49.8%) and cataract (42.7%). The prevalence of unilateral blindness is 1.2% (95% CI, 0.9-1.4), often caused by cataract, corneal scar, or phthisis. Trauma due to landmine explosions and war-related injuries was frequently the underlying etiology in subjects with phthisis, corneal scarring, or other pathology.CONCLUSIONS: The prevalence of blindness and low vision in Cambodia is relatively high compared to other developing countries. Most of the causes of blindness and low vision are treatable or preventable. Landmines and other war-related injuries are an important cause of ocular injury. These results will assist in developing a national plan for the prevention of blindness in Cambodia.     

山东省莱芜市白内障手术复明效果及术后并发症的调查

目的 了解白内障手术后的复明情况,并探讨其影响因素及有效的解决方法。方法 采用大样本含量分层整群随机抽样法对山东省莱芜市人群进行普查,记录白内障患者的手术类型、术后视力及术后并发症情况,将结果进行统计学分析。结果 共查出白内障术后患者1089例（1274只眼）。盲和低视力的发生率分别为4.87%和23.70%。术后发生角膜失代偿,继发性青光眼、晶状体后囊膜混浊、黄斑囊祥水肿和视网膜脱离者650只眼（51.02%）,治疗后因这些术后并发症导致的盲及低视力发生率由治疗前的4.87%、23.70%分别降至1.96%和6.01%。白内障针拨术和囊内白内障摘除术的手术脱盲率和最终脱残率最低,术后并发症的发生率最高。结论 适当选择白内障手术类型;对农村地区白内障术后患者进行定期随诊及普查,及时发现,治疗术后并发症,对提高白内障手术的脱盲率和脱殖率具有极为重要的意义。     

甘肃省平凉市崆峒区人群盲和低视力现况调查

目的:探讨与了解甘肃省平凉市崆峒区人群盲与低视力的患病率及致病原因。方法:应用横断面研究的流行病学调查方法,以村(社区)为基础,采用随机整群抽样原则抽取6个乡镇2个街道办事处作为调查地点。采用世界卫生组织制定的盲与低视力标准,对全区按0.719%抽样比例抽取样本进行盲与低视力的流行病学调查。结果:检录3235例中,受检人数为2801例,受检率为86.58%,双眼盲21例,盲率为0.75%(男0.59%,女0.91%);双眼低视力125例,低视力患病率为4.46%(男3.73%,女5.16%),≥60岁以上盲与低视力患者的患病率明显增高。致盲病因前三位的眼病依次为白内障(47.62%)、角膜病(14.29%)、青光眼(14.29%)。结论:崆峒区人群中盲和低视力的眼病以白内障居首位,因此手术治疗白内障仍是今后防盲治盲工作的首要任务。     

Blindness and Eye Disease in Cambodia

Purpose: To assess the prevalence and etiology of blindness and low vision and to assess the prevalence of common eye diseases in central Cambodia. Methods: In this cross-sectional, population-based study, 6,558 residents of Kandal Province, Cambodia were registered, and 5,803 (88.5%) were interviewed and examined. This house-to-house survey was conducted by a team consisting of a senior ophthalmologist, a Cambodian eye doctor, and eight Cambodian eyecare workers. Results: The prevalence of bilateral blindness (visual acuity <3/60) is 1.1% (95% confidence interval [CI], 0.9–1.4), and an additional 4.4% (95% CI, 3.9–5.0) have low vision (visual acuity < 6/18, ≥3/60 in the better eye). The major causes of bilateral blindness are cataract (67.4%), phthisis (6.1%), uncorrected refractive error (6.1%), corneal scar (5.3%), uncorrected aphakia (3.0%), trachoma corneal scar (3.0%), optic atrophy (3.0%), and others (6.1%). The major causes of low vision are uncorrected refractive error (49.8%) and cataract (42.7%). The prevalence of unilateral blindness is 1.2% (95% CI, 0.9–1.4), often caused by cataract, corneal scar, or phthisis. Trauma due to landmine explosions and war-related injuries was frequently the underlying etiology in subjects with phthisis, corneal scarring, or other pathology.Conclusions: The prevalence of blindness and low vision in Cambodia is relatively high compared to other developing countries. Most of the causes of blindness and low vision are treatable or preventable. Landmines and other war-related injuries are an important cause of ocular injury. These results will assist in developing a national plan for the prevention of blindness in Cambodia.     

我国白内障的流行病学调查资料分析

目的 探讨我国白内障的患病率与各地检查条件、诊断标准及地理环境的关系。方法 采用世界卫生组织盲与低视力标准,对全国抽样调查资料进行统计学分析。结果 双眼视力〈０．３的白内障患者约５００万人,患病率为０．４６％;盲与低视力的患病率分别为０．４３％和０．５８％。盲人中白内障致盲占４１．０６％;低视力患者中４９．３８％为白内障所致;白内障致老年盲（年龄≥６０岁）及低视力占７３．１３％。以晶体混及视力〈０