Prevalence and causes of visual impairment in an elderly Chinese population in Taiwan: the Shihpai Eye Study

OBJECTIVE: Few population-based data on the prevalence and causes of visual impairment are available from East Asia. The purpose of this study was to determine the prevalence and causes of visual impairment in an elderly Chinese population in Taiwan. DESIGN: Population-based cross-sectional study. PARTICIPANTS: The Shihpai Eye Study was a survey of vision and ocular disease among an elderly Chinese population 65 years of age or older residing in Shihpai, Taiwan. A random sample of 2045 elderly residents was identified and selected from the household registration databank. Among them, 1361 (66.6%) underwent a detailed ophthalmic examination. METHODS: The ophthalmic examination included best-corrected visual acuity measurements using standardized protocols. Visual acuity was assessed with a Snellen E chart. The major cause of visual loss was identified for all participants who were visually impaired. MAIN OUTCOME MEASURES: Low vision and blindness were defined as a best-corrected visual acuity in the eye with better vision worse than 20/60 to a lower limit of 20/400 and worse than 20/400, respectively, according to World Health Organization categories of visual impairment. RESULTS: The mean age of the participants was 72.2 (range, 65-91) years old. A total of 40 participants met the World Health Organization criteria of low vision, and 8 were diagnosed as blind. The rate of blindness and low vision was estimated to be 0.59% (95% confidence interval, 0.25%, 1.16%) and 2.94% (95% confidence interval, 2.11%, 3.99%), respectively. There was a significant increase in the rate of low vision (P<0.001) from 0.83% at 65 to 69 years of age to 8.33% at age 80 years or older. There was no gender difference in the prevalence of blindness or low vision. The leading cause of visual impairment was cataract (41.7%), followed by myopic macular degeneration (12.5%) and age-related macular degeneration (10.4%). CONCLUSIONS: The rate of blindness and low vision is close to that reported for other developed countries. The high frequency of myopic macular degeneration as a major cause of visual loss, however, is not observed in European-derived populations. Specific prevention or low-vision rehabilitation programs should be developed for the elderly Chinese population.     

Prevalence and causes of visual impairment in elderly Amis aborigines in eastern Taiwan (the Amis Eye Study)

Purpose

To investigate the prevalence and causes of visual impairment in elderly Amis aborigines in Eastern Taiwan.

Methods

Population-based cross-sectional study of visual impairment of elderly Amis (65?years of age or older). We conducted ocular examinations on 2,316 participants, which represent 61.2?% of the elderly population. We used WHO criteria to identify visual impaired subjects, and the causes were analyzed.

Results

Ninety-four subjects were identified with low vision and nineteen were blind. The prevalence of low vision was 4.06?% (95?% confidence interval, 3.26, 4.56?%); that of blindness was 0.82?% (95?% confidence interval, 0.45, 1.19?%). Cataracts (47.79?%) were the main cause of visual impairment, followed by age-related macular degeneration (15.93?%), corneal opacity (7.96?%), optic neuropathy (7.96?%), diabetic retinopathy (5.31?%), and retinitis pigmentosa (2.65?%). Glaucoma was a minor cause of visual impairment. There were no significant gender differences in the prevalence and specific causes of visual impairment.

Conclusion

The prevalence of treatable causes of vision impairment, for example cataracts and corneal opacity, is high among the elderly Amis aborigines. They would, therefore, benefit from a more aggressive and in-depth eye-care program as a blindness-prevention strategy.     

Trends in blind and low vision registrations in Taipei City

PURPOSE: To determine the overall reported incidence and causes of registrable blindness and low vision in Taipei, Taiwan, that have occurred in the previous 10 years. METHODS: Study data were obtained from disability identification registration forms completed between January 1995 and December 2004. Definitions of low vision and blindness were defined by WHO criteria: low vision included visual acuity worse than 6/18 (20/60) to a lower limit of 3/60 (20/400). Blindness was defined as visual acuity worse than 3/60 (20/400) in the better eye with best possible correction. RESULTS: There were 3151 registrations for visual impairment during the study period. A total of 239 registrations were excluded due to insufficient data. Of the remaining 2912 (1518 males and 1394 females), 640 males and 647 females were legally blind (44.20%). A total of 878 males and 747 females were partially sighted. The six leading causes of low vision and blindness, in decreasing frequency, were glaucoma, optic neuropathy, diabetic retinopathy, retinitis pigmentosa, age-related macular degeneration, and myopic macular degeneration. CONCLUSIONS: The proportions of new registrations owing to glaucoma, diabetic retinopathy, age-related macular degeneration, and myopic macular degeneration have changed significantly since 2000; the proportion due to diabetic retinopathy has increased.     

Causes of blindness and visual impairment in a population-based sample of U.S. Hispanics

OBJECTIVE: To describe the causes of blindness and visual impairment in a population-based sample of Hispanics. DESIGN: A cross-sectional study. PARTICIPANTS: A random sample of 4774 Hispanic residents of Santa Cruz and Pima Counties in Southern Arizona aged 40 years and older who participated in Proyecto VER (Vision Evaluation and Research). TESTING: Subjects were interviewed and underwent a thorough ophthalmic examination. Presenting and best-corrected visual acuity was determined using the Early Treatment of Diabetic Retinopathy Study protocol, followed by a standardized ophthalmic examination to determine the causes of visual loss. Anterior and posterior segment specialists in ophthalmology confirmed the causes. MAIN OUTCOME MEASURES: Causes of visual loss (best-corrected acuity worse than 20/40). RESULTS: The response rate of eligible participants was more than 70%. Best-corrected acuity in the better seeing eye worse than 20/40 increased from 0.3% in those aged 40 to 49 to 5.6% in those aged 65 and older. The leading cause was cataract, accounting for 42% of all visual loss, followed by age-related macular degeneration (15%), and diabetic retinopathy (13%). Among 14 people who were bilaterally blind, open-angle glaucoma was the leading cause. Women had higher age-adjusted prevalence of severe cataract compared with men and were more likely to be visually impaired from cataract, diabetic retinopathy, and open-angle glaucoma, although gender differences were not statistically significant. CONCLUSIONS: Causes of visual impairment differ from those reported in Caucasian populations, with open-angle glaucoma being the leading cause of blindness. Further work on gender-based obstacles to eye care in the Hispanic community may be warranted.     

Ophthalmic plaque radiotherapy for age-related macular degeneration associated with subretinal neovascularization

PURPOSE: To evaluate ophthalmic plaque radiotherapy for the treatment of subretinal neovascularization associated with age-related macular degeneration. METHODS: In a prospective phase I clinical trial, we treated 23 patients (23 eyes) with ophthalmic plaque radiotherapy for subfoveal exudative macular degeneration. Palladium 103 ophthalmic plaque brachytherapy was delivered to a retinal apex dose of 1,250 to 2,362 cGy (rad). Early Treatment Diabetic Retinopathy Study type visual acuity determinations, ophthalmic examinations, and angiography were performed before and after treatment. Clinical evaluations were performed in a nonrandomized and unmasked fashion. RESULTS: Patients were followed up for a mean (+/-SD) of 19 +/- 10.7 months (range, 3 to 37 months). Six months after radiation therapy, three (16%) of 19 eyes had lost 3 or more lines of best-corrected visual acuity; 12 months after radiation therapy, four eyes (31% of 13 eyes), and 24 months after radiation therapy, only two (22% of nine eyes) lost 3 or more lines of visual acuity. No eye suffered sudden irreversible loss of central vision. No radiation retinopathy, optic neuropathy, or cataract could be attributed to radiotherapy within this follow-up period. CONCLUSION: Ophthalmic plaque radiotherapy can be used to treat neovascular age-related macular degeneration. In contrast to external beam radiotherapy, ophthalmic plaque radiotherapy is a unilateral treatment, which allows a larger dose to be delivered to the macula with less irradiation of normal ocular structures. We have found no sight-limiting complications at the doses, dose rates, and follow-up evaluated in this study.     

杭州市下城区50岁及以上人群眼病流行病学调查

目的：调查杭州市下城区50岁及以上人群眼部疾病的患病情况及盲和中、重度视力损伤的患病率及病因。方法：横断面调查研究。于2015年4-8月期间采用整群随机抽样方法,从杭州市下城区8个街道共抽取50岁及以上人群2 953例,对其进行视力、屈光状态、眼压等检查,分析不同年龄、性别和受教育程度人群盲和中、重度视力损伤的患病率及病因。各数据间的比较采用 χ 2 检验和趋势χ 2 检验。结果：共2 363例接受并完成了检查,受检率为80%,人群中盲和中、重度视力损伤的患病率为1.6%（38例）,并随着年龄增长而上升（ χ 2 =38.094,P < 0.001）;文化程度越低,盲的患病率越高（ χ 2 =39.497,P < 0.001）。导致盲和中、重度视力损伤的主要原因有眼底异常（30眼,39.5%）、白内障（26眼,34.2%）、青光眼（12眼,15.8%）等。人群中眼病患病率由高到低依次为未矫正的屈光不正（2 048例,86.7%）、白内障（1 065例,44.7%）、翼状胬肉（219例,9.3%）、年龄相关性黄斑变性（81例,3.5%）、青光眼（52例,2.2%）、斜视（46例,2.0%）、糖尿病视网膜病变（39例,1.7%）。结论：杭州市下城区50岁及以上人群常见的眼部疾病是未矫正的屈光不正、白内障。盲和中、重度视力损伤的患病率较低,其中眼底异常、白内障是导致盲和中、重度视力损伤的主要原因。     

Low vision in Nigerians with diabetes mellitus

Objectives: To determine the prevalence and causes of low vision in diabetes mellitus patients in Nigeria. Materials and methods: All consecutive new patients seen at the Diabetic Eye Clinic, Nnamdi Azikiwe University Teaching Hospital Nnewi Nigeria, between March 1997 and September 1998 were the subjects of the study. Examination methods included interviewer-administered structured questionnaire, visual acuity test, external eye examination, refraction, tonometry, gonioscopy, binocular indirect ophthalmoscopy and slit lamp fundus examination with 78D non-contact lens. Results: Of the 100 new patients examined, 47 (47%) did not know that diabetes could lead to visual loss; 53 (53%) had not been examined by any eye health worker. Eighteen patients (18%) were bilaterally blind and 26 (26%) had monocular blindness; visual impairment was present in the better eyes of 30 patients (30%), with 20 (20%) having bilateral visual impairment. Glaucoma, cataract, diabetic retinopathy, central retinal vein occlusion, age-related macular degeneration, and leukoma were the causes of blindness. Visual impairment was due to diabetic macular edema, ametropia, cataract, age-related macular degeneration, glaucoma, uveitis and branch retinal vein occlusion. Conclusion: The causes of low vision in the patients are treatable and visual defects from them are thus avoidable. It is recommended that (a) all diabetics be made aware that diabetic complications cause visual loss; (b) laser photocoagulation facilities be provided for treating diabetic retinopathy.     

Visual status and ocular morbidity in older adults living in residential care

Background

The frequency of visual impairment and blindness increases with age and is more prevalent among older adults living in residential care centers. The main aim of this study was to assess the visual status and determine the prevalence and major causes of visual impairment and blindness among the older adults living in residential care centers of Kathmandu Valley, Nepal.

Methods

A cross-sectional study was conducted on 385 residents of 60?years or older residing in seven residential care centers of Kathmandu Valley. Presenting distance visual acuity was assessed in each eye with a Snellen chart at 6-m distance in non-standardized outdoor illumination. Objective and subjective refractions were performed and the best-corrected distance visual acuity was considered in the better eye. Near acuity was assessed binocularly with The Lighthouse Near Acuity Card. Complete anterior and posterior segment examination was carried out.

Results

The mean age of residents was 74.34?±?8.19?years. The majority was female residents (78.2?%). The prevalence of visual impairment and blindness was 43.70?%. Adequate refractive correction could alone reduce the prevalence of visual impairment and blindness by 15.40?%. Cataract was the leading cause of visual impairment and blindness, which was followed by age-related macular degeneration, corneal opacity, glaucoma, and macular scar.

Conclusions

The prevalence of visual impairment and blindness is significant among the older adults living in residential care centers. The frequency of visual impairment and blindness can be prevented by adequate refractive correction, frequent eye examination, and appropriate high use of cataract surgery.     

The Chinese American Eye Study: Design and Methods

Abstract

Purpose: To summarize the study design, operational strategies and procedures of the Chinese American Eye Study (CHES), a population-based assessment of the prevalence of visual impairment, ocular disease, and visual functioning in Chinese Americans.

Methods: This population-based, cross-sectional study included 4570 Chinese participants aged 50 years and older, residing in the city of Monterey Park, California. Each eligible participant completed a detailed interview and eye examination. The interview included an assessment of demographic, behavioral and ocular risk factors and health-related and vision-related quality of life. The eye examination included measurements of visual acuity, intraocular pressure, visual fields, fundus and optic disc photography, a detailed anterior and posterior segment examination, and measurements of blood pressure, glycosylated hemoglobin levels, and blood glucose levels.

Results: The objectives of the CHES are to obtain prevalence estimates of visual impairment, refractive error, diabetic retinopathy, open-angle and angle-closure glaucoma, lens opacities, and age-related macular degeneration in Chinese Americans. In addition, outcomes include effect estimates for risk factors associated with eye diseases. Lastly, CHES will investigate the genetic determinants of myopia and glaucoma.

Conclusion: The CHES will provide information about the prevalence and risk factors of ocular diseases in one of the fastest growing minority groups in the United States.     

The Los Angeles Latino Eye Study: design, methods, and baseline data

OBJECTIVE: To describe the study design, operational strategies, procedures, and baseline characteristics of the Los Angeles Latino Eye Study (LALES), a population-based assessment of the prevalence of visual impairment, ocular disease, and visual functioning in Latinos. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in Los Angeles, California. METHODS: A detailed interview and eye examination were performed on each eligible participant. The interview included an assessment of demographic, behavioral, and ocular risk factors and health-related and vision-related quality of life. The eye examination included a measurement of visual acuity, intraocular pressure, and visual fields; fundus and optic disc photography; a detailed anterior and posterior segment examination; and measurement of blood pressure, glycosylated hemoglobin levels, and blood glucose levels. MAIN OUTCOME MEASURES: Prevalence of visual impairment, blindness, cataract, glaucoma, diabetic retinopathy, and age-related macular degeneration constitute the study's primary outcome variables. Secondary outcomes include odds ratios for risk factors associated with eye disease, health-related quality of life, and vision-related quality of life. Response rates and baseline characteristics are presented. RESULTS: Of the 7789 individuals eligible for LALES, 6357 (82%) had a clinical examination; an additional 524 completed only an in-home interview. The majority of participants were female (58%), the average (+/- standard deviation) age was 54.9 (+/-10.8) years, and 80.0% were of Mexican origin and 0.4% self-identified as American Indian or Alaskan Native. The age distribution of LALES participants was similar to that of Latinos of Mexican origin in the rest of the United States. CONCLUSION: The LALES has recruited Latinos 40 and older for an ophthalmic epidemiologic study. The LALES cohort will provide information about the prevalence and risk factors of ocular disease in the largest and fastest growing minority in the United States.     

2009年上海市宝山区大场社区60岁及以上人群盲和低视力患病率调查

目的 探讨上海市宝山区大场社区60岁及以上人群的盲和低视力患病率、致盲原因及其相关因素。方法 横断面现况调查研究。由上海市眼病防治中心和上海市宝山区疾病预防控制中心于2009年10至12月期间对上海市宝山区大场社区60岁及以上并在当地居住10年以上的常住户籍人口进行随机整群抽样调查。对调查对象完成视力、眼压、验光、裂隙灯显微镜、免散瞳数字眼底照相等检查,采用世界卫生组织视力损伤标准和日常生活视力和视力损伤标准确立盲或低视力,并明确主要致盲原因。组间率的比较采用卡方检验。结果 实际受检4545人,受检率为87.42％。受检人群均为近10年内随着城市化进程从原农村人口转变而来的城市人口。按照世界卫生组织视力损伤标准：双眼盲30人,患病率0.67％;双眼低视力145人,患病率3.19％。白内障、黄斑变性、眼球萎缩或缺如、青光眼、糖尿病视网膜病变（或角膜病）是前5位致盲眼病。女性低视力患病率高于男性,差异有统计学意义(x2 =4.88,P＜0.05)。按照日常生活视力和视力损伤标准：双眼盲39人,患病率0.86％,双眼低视力401人,患病率8.82％;75岁后成为视力损害的高速发展期。白内障、未矫正的屈光不正、黄斑变性、眼球萎缩或缺如、青光眼是前5位致盲原因。女性低视力患病率高于男性,差异有统计学意义(x2=13.345,P＜0.01)。结论 在上海市城市化进程较快的老龄化社区中,白内障、未矫正的屈光不正、黄斑变性是引起日常生活视力盲的前3位原因,女性低视力患病率明显高于男性。对这类社区居民需要进行更多的有针对性眼的保健教育与服务工作。     

Prevalence and causes of visual impairment according to World Health Organization and United States criteria in an aged, urban Scandinavian population: The Copenhagen City Eye Study

PURPOSE: To evaluate the prevalence and causes of visual impairment in an epidemiologic study of aged, urban individuals in Denmark. DESIGN: Cross-sectional study. PARTICIPANTS: The study population consisted of 1000 randomly selected residents aged 60 to 80 years in Copenhagen, Denmark. Of 976 eligible persons, 946 (96.9%) could be examined. Information about best-corrected visual acuity (VA) was obtained from 944 cooperative persons (96.7%). METHODS: Data from the Copenhagen City Eye Study were used to assess the cause-specific prevalence of visual impairment as defined by the World Health Organization (WHO) (VA worse than 20/60-20/400 in the better eye) and the criteria used most commonly in the United States (VA worse than 20/40 but better than 20/200 in the better eye). Eligible subjects underwent an extensive ophthalmologic examination at The National University Hospital of Denmark. MAIN OUTCOME MEASURES: Best-corrected VA and primary causes of visual impairment. RESULTS: The prevalence of low vision according to the WHO definition ranged from 2.6% in subjects aged 70 to 74 years to 4.8% in subjects 75 to 80 years of age, with an age-adjusted relative prevalence of 1.58%. Using the U.S. definition, the overall age-adjusted prevalence of visual impairment was 2.9%. The causes of visual impairment according to the WHO criteria were age-related macular degeneration (AMD) (44.4%), cataract (33.3%), glaucoma in combination with cataract (11.1%), myopic macular degeneration (5.6%), and diabetic retinopathy (5.6%). However, according to the U.S. criteria, cataract was the most frequent primary cause (50.0%) and AMD was the second most frequent primary cause (34.4%) of visual impairment. Furthermore, using the U.S. criteria diabetic retinopathy was revealed as equally important as AMD and cataract as a cause of visual impairment among persons aged 65 to 69 years (33.3%). CONCLUSIONS: Increasing age was an independent predictor of visual impairment. Cataract and AMD were the leading causes. Adequate implementation of surgery to treat cataract could reduce visual impairment by 33.3% according to the WHO criteria and by 50% according to the U.S. criteria.     

Prevalence of Visual Impairment in the Adult Japanese Population by Cause and Severity and Future Projections

Purpose: To present a comprehensive estimate of the total number of people with visual impairment in the adult Japanese population by age, gender, severity and cause, and to estimate future prevalence based on population projections and expected demographic changes.

Methods: Definitions of visual impairment used in this study were based on the United States criteria. Total visual impairment was calculated as the sum of low vision and blindness. The prevalence estimates were based on input from a number of Japanese epidemiological surveys, census material and official population projections.

Results: There were an estimated 1.64 million people with visual impairment in 2007 in Japan. Of these, 187,800 were estimated to be blind. The prevalence of visual impairment in Japan increased with age and half of the people with visual impairment were aged 70 years or older. The leading causes of visual impairment in Japan were glaucoma (24.3%), diabetic retinopathy (20.6%), degenerative myopia (12.2%), age-related macular degeneration (10.9%), and cataract (7.2%). These five major causes comprised three-quarters of all visual impairment. The prevalence of visual impairment was projected to increase from 1.3% of the population in 2007 to 2.0% by 2050.

Conclusions: This comprehensive study presents the prevalence of total visual impairment in the adult Japanese population. The projected increases in the prevalence of visual impairment over time reflect the demographic changes of a declining and aging Japanese population. These projections highlight that the burden of disease due to visual impairment and imposed on society is likely to increase.     

Contributing ocular comorbidity to end-of-life visual acuity in medically treated glaucoma patients,ocular hypertension and glaucoma suspect patients

AimTo assess the visual acuity at the end of life in glaucoma suspect patients, ocular hypertension, and patients treated for glaucoma and to find factors contributing to a reduced visual acuity in this cohort of deceased patients.MethodsIn a cohort of 3883 medically treated glaucoma patients, glaucoma suspect, or patients with ocular hypertension assembled in 2001–2004, 1639 were deceased. Patient data were collected from electronic and paper patient files. The files of 1378 patients were studied and the last measured visual acuity and ocular comorbidities influencing the visual acuity were extracted.ResultsOur results show that only 37.2% of patients had no visual impairment in either eye, 30.5% was visually impaired or blind in both eyes and 4.1% was blind in both eyes, all based on VA. The most common contributing factors for severe visual impairment or blindness (prevalence ≥ 1%) were: glaucoma, retinal vein occlusion, dry and exudative age-related macular degeneration, past retinal detachment, amblyopia, diabetic retinopathy, anterior ischemic optic neuropathy, trauma, decompensated cornea, past keratitis, enucleation, corneal transplantation, and macular hole.ConclusionsDespite the current advanced treatment modalities for glaucoma, 30.5% of patients had a VA < 0.5 in both eyes and 4.1% was blind in both eyes. However, this disability cannot be confidently attributed only to glaucoma. Besides glaucoma, most common contributing factors were among others retinal and macular diseases. Patient management in glaucoma should be based on more than lowering the intraocular pressure to prevent blindness at the end of life.Subject terms: Optic nerve diseases, Pattern vision     

Translocation of the macula for management of subfoveal choroidal neovascularization: comparison of results in age-related macular degeneration and degenerative myopia

PURPOSE: To report the results of limited macular translocation in subfoveal choroidal neovascularization resulting from age-related macular degeneration or degenerative myopia. METHODS: The first consecutive 32 patients (23 age-related macular degeneration eyes and nine myopic eyes) were operated on with the limited macular translocation technique described by de Juan. Before and after surgery, a complete examination included fluorescein and indocyanine-green angiographies and optical coherence tomography. Mean follow-up was 9 months in the age-related macular degeneration group (range, 6 to 14 months) and 10 months in the myopic group (range, 6 to 15 months). RESULTS: The improvement in visual acuity was better in the myopic group than in the age-related macular degeneration group and was correlated with younger age in the myopic group (P <.05). At the end of follow-up, visual acuity improved by 2 lines or more in seven age-related macular degeneration eyes (30%), including four eyes (13%) with an improvement of 6 lines or more, and in six myopic eyes (67%), including two eyes (22%) with an improvement of 6 lines or more. Final visual acuity was unchanged in four age-related macular degeneration eyes (17%) and three myopic eyes (33%), and decreased in 12 age-related macular degeneration eyes (52%). Conversely, the mean foveal displacement was greater in age-related macular degeneration than in myopia (1,105 microm and 685 microm, respectively; P <.05). Main complications were retinal detachment (six eyes), neovascularization at the injection site (two eyes), and recurrence of neovascularization (43% of the age-related macular degeneration group and 11% of the myopic group). CONCLUSIONS: Limited macular translocation allowed a significant improvement in visual acuity in some eyes with subfoveal neovascularization and resulted in a moderate rate of complications. Longer follow-up and additional studies are required to confirm these findings.     

Prevalence and causes of visual impairment and blindness among 9980 Scandinavian adults: the Copenhagen City Eye Study

PURPOSE: To investigate the age-specific prevalence and causes of visual impairment and blindness in an epidemiologic study of an adult Scandinavian population. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: The study population was composed of 9980 persons, ages 20 to 84, from the general population of Copenhagen, Denmark. METHODS: This study is based on the third Copenhagen City Heart Study (CCHS III). Participants who reported visual impairment or blindness or had difficulty reading newspaper type and used prescribed eye medications were contacted from 1999 through 2000 and asked to complete a standardized interview concerning their ophthalmologic history. Verification of objective ophthalmologic data was done with a validated questionnaire response method. MAIN OUTCOME MEASURES: Best-corrected visual acuity in the better eye and primary causes of visual impairment and blindness. Visual impairment was defined as visual acuity worse than 20/40 but better than 20/200, and blindness was defined as visual acuity of 20/200 or worse. RESULTS: The age-standardized prevalence rates of visual impairment and blindness were 0.66% and 0.20%, respectively, and rose significantly with age (P<0.001). For persons 20 to 64 years, myopia-related retinal disorders, diabetic retinopathy, optic neuropathy, and retinitis pigmentosa were the most common causes of impaired vision. For persons 65 to 84 years, cataract was the most common cause of visual impairment, whereas age-related macular degeneration was the major cause of blindness. CONCLUSIONS: Visual impairment and blindness are strongly associated with increasing age, and the causes are determined by age. Among persons aged 20 to 64 years, an intervention for the predominating eye diseases might have some effect. Among those aged 65 to 84 years, cataract surgery could reduce visual impairment by one third.     

Color Doppler imaging of the retrobulbar circulation in non-exudative and exudative age-related macular degeneration

PURPOSE: To study ocular perfusion in the ophthalmic artery, central retinal artery, nasal and temporal posterior ciliary : arteries in non-exudative and exudative age-related macular degeneration. MATERIAL AND METHODS: Twenty five subjects with non-exudative age-related macular degeneration were compared to twenty five subjects with exudative age-related macular degeneration and to twenty five age-matched control subjects. Color Doppler imaging measured peak systolic velocity (PSV) and end diastolic velocity (EDV) in the ophthalmic artery, central retinal artery, nasal and temporal posterior ciliary arteries of one eye. The resistivity index (RI) and the pulsatility index (PI) were calculated. RESULTS: There were statistically significant differences between: subjects with non-exudative age-related macular degeneration and subjects with exudative age-related macular degeneration in EDV, RI and PI in the ophthalmic artery and PSV in the temporal posterior ciliary artery, subjects with non-exudative age-related macular degeneration and control subjects in RI in central retinal artery, subjects with non-exudative age-related macular degeneration and control subjects in RI and PI in nasal posterior ciliary artery, subjects with exudative age-related macular degeneration and control subjects in PI in nasal posterior ciliary artery. CONCLUSIONS: The study results showed reduced ocular blood flow in patients with non-exudative age-related macular degeneration compared to patients with exudative age-related macular degeneration and to control subjects. The higher RI in central retinal artery in non-exudative age-related macular degeneration compared to control subjects, suggest there may be a more generalized perfusion abnormality beyond the choroid.     

National Registry for the Blind in Israel: Estimation of prevalence and incidence rates and causes of blindness

OBJECTIVE To describe the population registered as blind in Israel and estimate the prevalence and incidence of blindness, by age, sex and the causes of blindness. METHODS Israel has maintained a Registry for the Blind since 1987. Patients are identified by ophthalmologists and registered if they have a visual acuity of =0.05 (20/400) or a visual field of &lt;20 degrees radius in their better eye. The Registry consists of all eligible citizens living in Israel at the time of registration. This report includes prevalence data on 18,891 persons enrolled in the Registry from 1987–1999 and still alive and living in Israel in 1999, and incidence data on 2,511 persons newly registered in 1999. Data were collected on visual acuity and visual field loss, cause of blindness, and patient demographics. RESULTS In 1999, the estimated prevalence rate of blindness nation-wide was 0.31% and the estimated incidence rate was 0.037%. The major causes of blindness in the complete Registry were age related macular degeneration (AMD) and glaucoma (14%), followed by diabetic retinopathy (11%), cataract and myopic maculopathy (10%), and optic atrophy (8.4%). The leading causes of newly diagnosed blindness were age-related macular degeneration (AMD) (20%), glaucoma (14%), diabetic retinopathy (12%), myopic maculopathy (11%), and optic atrophy and cataract (10%). CONCLUSIONS Israel has one of the few nationwide blindness registries in the world. The prevalence and incidence of blindness in Israel appear to be comparable to other western countries Comparisons are difficult because of different definitions of blindness, age distributions, and the uniqueness of the Israeli Registry.     

雷珠单抗和PDT治疗湿性AMD的疗效比较

目的：比较雷珠单抗和光动力疗法(photodynamic therapy, PDT)治疗湿性年龄相关性黄斑变性(age-related macular degeneration, AMD)的临床疗效。

方法：回顾性分析23例PDT治疗的湿性AMD患者和23例予雷珠单抗玻璃体腔内注射治疗的湿性AMD患者的资料,比较两组在治疗后 1,3,6mo的视力、OCT及FFA变化情况。

结果：两组患者术后1,3mo视力均得到明显提高,两组在统计学意义上无显著差异,雷珠单抗组有2例(9%)患者在治疗后6mo出现视力回降现象,PDT组患者在术后3mo及术后6mo视力变化稳定。

结论：雷珠单抗和PDT治疗湿性AMD,均能有效控制湿性AMD患者病情发展并能改善患者视力,两种疗法疗效的比较在短期内无统计学意义,但是术后6mo,PDT的稳定性优于雷珠单抗。