-
[show abstract]
[hide abstract]
ABSTRACT: The aim of this work is to prospectively assess the relationship between trans-laminar cribrosa pressure difference and neuroretinal rim area as morphologic surrogate of glaucomatous optic nerve damage.
The study included 22 patients with high-pressure glaucoma, 13 patients with normal-pressure glaucoma, and 17 subjects with ocular hypertension. All participants underwent a standardized ophthalmologic examination including confocal laser scanning tomography of the optic nerve head and computerized perimetry and a neurologic examination including measurement of the lumbar cerebrospinal fluid (CSF) pressure. The trans-lamina cribrosa pressure difference was calculated as difference of intraocular pressure minus lumbar CSF pressure.
Neuroretinal rim area (p = 0.006; correlation coefficient r = -0.38) and mean visual field defect (p = 0.008; r = 0.38) were significantly associated with trans-lamina cribrosa pressure difference. The probability of error was lower (i.e., the p value were lower) and the correlation coefficients were higher for the associations between rim area/visual field defect with trans-lamina cribrosa pressure difference than for the associations between rim area/visual field defect and intraocular pressure or lumbar CSF pressure.
The trans-lamina cribrosa pressure difference as the difference of intraocular pressure minus the lumbar CSF pressure was the main pressure parameter associated with the amount of glaucomatous optic nerve damage. This may suggest that the CSF pressure as trans-lamina cribrosa counter pressure against the intraocular pressure may play some role in the pathogenesis of glaucomatous optic neuropathy.
Albrecht von Graæes Archiv für Ophthalmologie 04/2011; 249(7):1057-63. · 2.17 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To examine in an intra-individual comparison whether cataract is associated with age-related macular degeneration (AMD).
The population-based Beijing Eye Study included 4,439 subjects (age: 40+ years) out of 5,324 subjects invited to be examined. Using lens and fundus photographs, the amount of AMD was graded according to the Wisconsin Age-Related Maculopathy Grading system and the degree of cataract was graded using the system of the Age-Related Eye Disease Study.
Photographs with sufficient quality for bilateral examination of the lens and macula were available for 3,826 (86.2%) participants with a mean age of 55.3 ± 10.0 years (range: 40-90 years) and a mean refractive error of -0.38 ± 2.18 diopters (range: -20.13 diopters to +7.50 diopters). The side difference in presence of early AMD and late AMD respectively was not significantly associated with the inter-eye difference in the amount of nuclear cataract [P = 0.27 and P = 0.28 (r = 0.02) respectively), amount of cortical cataract (P = 0.12 and P = 0.05 respectively), and amount of subcapsular posterior cataract (P = 0.91 and P = 0.85 respectively). In a similar manner, the side difference in the presence of early AMD and late AMD was not significantly associated with the inter-eye difference in the presence of nuclear cataract (P = 0.99 and P = 0.99 respectively), cortical cataract (P = 0.25 and P = 1.00 respectively), and subcapsular posterior cataract (P = 0.59 and P = 0.05 respectively). The side difference in the number of macular drusen was not significantly associated with the inter-eye difference in the amount of nuclear cataract (P = 0.74), amount of cortical cataract (P = 0.19) and amount of subcapsular posterior cataract (P = 0.88). As a corollary, unilateral pseudophakia or aphakia was not significantly associated with inter-eye differences in the count (P = 0.59) of drusen, and overall presence of early AMD (P = 0.99) or late AMD (P = 0.99).
In an intra-individual, inter-eye comparison, avoiding interdependencies of systemic parameters, inter-eye difference was not significantly associated with any characteristics of age-related macular degeneration in either any type of cataract or in pseudophakia. This suggests that the development of cataract or cataract surgery did not markedly influence the development of age-related macular degeneration.
Albrecht von Graæes Archiv für Ophthalmologie 12/2010; 249(7):981-5. · 2.17 Impact Factor
-
American journal of ophthalmology 12/2009; 148(6):954. · 3.83 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To assess the relationship of hypertension with major eye diseases and other ocular parameters.
Population-based study.
The Beijing Eye Study is a population-based study that included 4439 Chinese subjects examined at the baseline examination in 2001; there was a follow-up examination in 2006, in which 3251 subjects participated, of whom 3222 had blood pressure measurements.
All participants underwent an ophthalmic examination, anthropometric measurements, and blood pressure measurement. Hypertension was defined as a systolic blood pressure >or=140 mmHg and/or diastolic blood pressure >or=90 mmHg, and/or self-reported current treatment for hypertension with antihypertensive medication.
Blood pressure and ocular parameters, including intraocular pressure and prevalence of major ophthalmic diseases.
Mean age of participants in the present study was 60.4+/-10.0 years. Hypertension was present in 1500 (46.6%) of the 3222 subjects who had their blood pressure measured. In multiple regression analysis, hypertension was associated with higher intraocular pressure (beta = 0.39; 95% confidence interval [CI], 0.12-0.66; P = 0.005), focal arteriolar narrowing (odds ratio [OR], 1.78; 95% CI, 1.34-2.36; P<0.001), arteriovenous nicking (OR, 1.50; 95% CI, 1.11-2.04; P = 0.009), generalized retinal arteriolar narrowing (OR, 1.65; 95% CI, 1.30-2.09; P<0.001), retinal vein occlusions (OR, 2.86; 95% CI, 1.21-6.80; P = 0.02), and diabetic retinopathy (OR, 1.90; 95% CI, 1.08-3.31; P = 0.02). Hypertension was not significantly associated with the prevalence of open-angle glaucoma (P = 0.19), angle-closure glaucoma (P = 0.15), age-related macular degeneration (AMD) (P = 0.73), nuclear cataract (P = 0.88), posterior subcapsular cataract (P = 0.30), cortical cataract (P = 0.10), or area of alpha zone (P = 0.05) or beta zone of parapapillary atrophy (P = 0.95).
In Chinese persons, while controlling for other systemic parameters, hypertension was associated with increased intraocular pressure, retinal microvascular abnormalities, and prevalence of retinal vein occlusion and diabetic retinopathy. Hypertension was not associated significantly with AMD, age-related cataract, or glaucoma.
Ophthalmology 10/2009; 116(12):2373-80. · 5.45 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the prevalence and causes of visual impairment among Chinese children aged 3 to 6 years in Beijing.
Population-based prevalence survey.
Presenting and pinhole visual acuity were tested using picture optotypes or, in children with pinhole vision < 6/18, a Snellen tumbling E chart. Comprehensive eye examinations and cycloplegic refraction were carried out for children with pinhole vision < 6/18 in the better-seeing eye.
All examinations were completed on 17,699 children aged 3 to 6 years (95.3% of sample). Subjects with bilateral correctable low vision (presenting vision < 6/18 correctable to >or= 6/18) numbered 57 (0.322%; 95% confidence interval [CI], 0.237% to 0.403%), while 14 (0.079%; 95% CI, 0.038% to 0.120%) had bilateral uncorrectable low vision (best-corrected vision of < 6/18 and >or= 3/60), and 5 subjects (0.028%; 95% CI, 0.004% to 0.054%) were bilaterally blind (best-corrected acuity < 3/60). The etiology of 76 cases of visual impairment included: refractive error in 57 children (75%), hereditary factors (microphthalmos, congenital cataract, congenital motor nystagmus, albinism, and optic nerve disease) in 13 children (17.1 %), amblyopia in 3 children (3.95%), and cortical blindness in 1 child (1.3%). The cause of visual impairment could not be established in 2 (2.63%) children. The prevalence of visual impairment did not differ by gender, but correctable low vision was significantly (P < .0001) more common among urban as compared with rural children.
The leading causes of visual impairment among Chinese preschool-aged children are refractive error and hereditary eye diseases. A higher prevalence of refractive error is already present among urban as compared with rural children in this preschool population.
American journal of ophthalmology 02/2009; 147(6):1075-81. · 3.83 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the causes of visual impairment and blindness in adult Chinese in an urban and rural region of Beijing, China.
Population-based prevalence survey.
From a rural region and an urban region of Greater Beijing, 4439 of 5324 > or=40-year-old invited subjects participated in the study (response rate, 83.4%). Using the World Health Organization (WHO) standard and the United States standard, blindness was defined as best-corrected visual acuity (BCVA) in the better-seeing eye of <20/400 and of <2/20, respectively, and visual impairment was defined as best-corrected vision of <20/60 and > or =20/400, and of <20/40 and > or =2/20, respectively.
Determination of BCVA, pneumotonometry, frequency doubling perimetry, evaluation of photographs of the fundus and lens, and clinical examination.
Causes of visual impairment and blindness.
Visual acuity measurements were available for 8816 eyes of 4409 subjects (99.3%). Using the WHO standard and the U.S. standard, 49 (1.1%) subjects and 95 (2.2%) subjects, respectively, had low vision, and 13 (0.3%) subjects and 15 (0.3%) subjects, respectively, were blind by definition. Taking the whole study population, the most frequent cause of low vision/blindness was cataract (36.7%/38.5%), followed by degenerative myopia (32.7%/7.7%), glaucoma (14.3%/7.7%), corneal opacity (6.1%/15.4%), and other optic nerve damage (2.0%/7.7%). Age-related macular degeneration (AMD) (2.0%/7.7%) and diabetic retinopathy (0%/7.7%) were responsible for a minority of cases. In subjects 40 to 49 years old, the most frequent cause of low vision and blindness was degenerative myopia. In the 50- to 59-year age group, the most frequent cause was cataract, followed by degenerative myopia. In the 60- to 69-year-old subjects and the > or =70-year group, the most frequent cause of low vision and blindness was cataract, followed by degenerative myopia and glaucoma.
The most frequent cause of low vision and blindness in adult Chinese is cataract, followed by degenerative myopia and glaucomatous optic neuropathy, with degenerative myopia dominating in younger groups and cataract dominating in elder groups. In contrast to studies in Western countries, AMD and diabetic retinopathy appear to play a minor role as a cause of visual impairment in elderly Chinese.
Ophthalmology 08/2006; 113(7):1134.e1-11. · 5.45 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The aim of the study was to evaluate the prevalence of under-corrected refractive error among elderly Chinese in the Beijing area.
The population-based, cross-sectional, cohort study comprised 4,439 subjects out of 5,324 subjects asked to participate (response rate 83.4%) with an age of 40+ years. It was divided into a rural part [1,973 (44.4%) subjects] and an urban part [2,466 (55.6%) subjects]. Habitual and best-corrected visual acuity was measured. Under-corrected refractive error was defined as an improvement in visual acuity of the better eye of at least two lines with best possible refractive correction.
The rate of under-corrected refractive error was 19.4% (95% confidence interval, 18.2, 20.6). In a multiple regression analysis, prevalence and size of under-corrected refractive error in the better eye was significantly associated with lower level of education (P<0.001), female gender (P<0.001), and age (P=0.001).
Under-correction of refractive error is relatively common among elderly Chinese in the Beijing area when compared with data from other populations.
Albrecht von Graæes Archiv für Ophthalmologie 08/2006; 244(7):871-3. · 2.17 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To determine the prevalence of lens opacities in the elderly Chinese population in an urban and a rural region of Beijing.
Population-based cross-sectional study.
The study included 4439 subjects of 5324 subjects invited to participate (response rate, 83.4%). The subjects were divided into a rural part (1973 subjects [44.4%]) and an urban part (2466 subjects [55.6%]). The study was limited to participants age 40 and older, and the mean age was 56.2+/-10.6 years (range, 40-101 years).
Nuclear, cortical, and posterior subcapsular lens opacities were assessed based on standardized slit-lamp photographs of the lens using a modification of the grading score of the Age-related Eye Disease Study (AREDS).
Grading score of the AREDS.
Lens data were provided for 4378 subjects (98.6%) of 4439 persons examined, which consisted of 8724 eyes. Prevalence of any cataract surgery was 1.3% (95% confidence interval [CI]: 1.0-1.7), which was statistically independent of gender (P = 0.51; odds ratio [OR]: 0.86; 95% CI: 1.00-1.34), rural area versus urban region (P = 0.25), and level of education (P = 0.84). Prevalence of any nuclear lens opacity was 82.0% (95% CI: 80.8-83.2); prevalence of any cortical lens opacity was 10.3% (95% CI: 9.4-11.3); and prevalence of any posterior subcapsular opacity was 4.3% (95% CI: 3.7-4.9). If grade 2 of nuclear lens opacity was considered to be normal, prevalence of nuclear cataract was 50.3% (95% CI: 48.8-51.8), and the overall prevalence of any cataract was 53.1% (95% CI: 51.6-54.6), increasing from 6.5% (95% CI: 5.2-7.8) in those subjects 40 to 49 years of age to 52.3% (95% CI: 47.4-55.3) in those who were 50 to 59 years of age, and to 97.8% (95% CI: 96.4-99.2) in those 70 years and older (P<0.001). Frequencies of any cortical cataract and any subcapsular posterior cataract were 10.3% (95% CI: 9.4-11.3) and 4.3% (95% CI: 3.7-4.9), respectively.
Cataracts are common among adult Chinese residents in Beijing, with age as the most important associated factor. In view of the relatively low rate of cataract surgery performed so far, one may expect a marked increase in the number of cataract surgeries to meet the visual needs of the growing elderly population in China.
Ophthalmology 05/2006; 113(5):747-55. · 5.45 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To estimate the prevalence and distribution of blindness and low vision in Northern China.
Population-based cohort study.
The Beijing Eye Study included 4438 subjects with an age of 40+ years. Mean age was 56.2 +/- 10.6 years (range, 40 to 101 years).
Forty-three (1.0%) individuals had low vision (<20/60 and >/=20/400 best-corrected vision), and 17 (0.4%) individuals were blind (best-corrected visual acuity in the better-seeing eye <20/400). Low vision/blindness were significantly associated with age (P < .001), myopic refractive error (P < .001), and level of educational background (P = .035). It was not associated with gender (P = .76) and rural vs urban area (P = .88).
Blindness or low vision affects approximately one in 100 Chinese older than 40 years. An estimated 4.1 million Chinese older than 40 years have low vision, and an estimated 1.6 million Chinese older than 40 years are blind.
American Journal of Ophthalmology 03/2006; 141(3):591-3. · 4.22 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate intraocular pressure (IOP) and its demographic associations in an urban and rural population in Northern China.
Population-based cohort study.
In the Beijing Eye Study, IOP was measured by noncontact pneumatonometry. Mean age was 56.20 +/- 10.59 years (range, 40-101 years).
Mean IOP was 16.11 +/- 3.39 mm Hg (median, 16 mm Hg; range, 7-60 mm Hg). In the rural group and the urban population group, respectively, IOP was significantly (P = .016 and P = .029, respectively) lower in the high-age group (>or=75 years) than in the middle-age group (55-64 years). In the rural group, IOP was additionally significantly lower in the age group of 40 to 44 years than in the middle-age group, which suggests a reversed U-like course. A multiple regression analysis revealed that IOP significantly increased with myopia (P = .024), and that it was statistically independent of rural area vs urban area (P = .12) and gender (P = .71).
In the Northern Chinese population, mean and median of IOP that is measured by pneumatonometry is 16 mm Hg with a normal range (mean +/- two SDs) of 10 to 22 mm Hg. In cross-sectional analysis, IOP slightly increased towards an age of 55 to 64 years and decreased towards higher ages. IOP increased with myopia. It was not associated with rural vs urban region or gender.
American Journal of Ophthalmology 11/2005; 140(5):913-5. · 4.22 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate refractive error and its demographic associations in an urban and rural population in northern China.
Epidemiological study.
The Beijing Eye Study is a population-based cohort study in northern China including 4439 subjects. Excluding pseudophakic and aphakic patients, the present study involved 4319 subjects. It was divided into a rural part (1905 [44.1%] subjects) and an urban part (2414 [55.9%] subjects). Mean age was 55.85+/-10.33 years (range, 40-90).
Standardized ophthalmologic examination. For statistical analysis, the spherical equivalent was converted to binary variables, and logistic regression was used to investigate the association with continuous or categorical independent variables.
Refractive error.
Mean refractive error measured -0.33+/-2.22 diopters (D) (range, -20.88 to +7.88). Myopia of >-0.50 D, -1.0 D, >-6.0 D, and >-8 D, respectively, occurred in 22.9% (95% confidence interval [CI], 21.7-24.2), 16.9% (95% CI, 15.8-18.0), 2.6% (95% CI, 2.2-3.1), and 1.5% (95% CI, 1.1-1.9) of the subjects, respectively. Myopic refractive error was associated significantly with younger age (P<0.001), urban region (vs. rural region) (P<0.001), higher educational background (P<0.001), higher degree of nuclear cataract (P<0.001), decreasing uncorrected visual acuity (UCVA) (P<0.001), decreasing best-corrected visual acuity (BCVA) (P<0.001), and female gender (P<0.001). Prevalence of high myopia (myopic refractive error >-8 D) was associated with age (P<0.001), female gender (P = 0.020), urban region (P = 0.023), and lower BCVA (P<0.001). Mean anisometropia was 1.09+/-2.03 D (median, 0.38; range, 0-22.0). Prevalence of anisometropia of > or =1 D was associated significantly with age (P<0.001), refractive error (P<0.001), BCVA (P<0.001), and region (P<0.001). Mean astigmatic error measured 0.62+/-0.90 D (median, 0.25; range, 0-7.50). Astigmatism of > or =1 D was associated significantly with age (P<0.001), lower UCVA (P = 0.003), lower BCVA (P<0.001), urban area (P<0.001), and degree of cortical cataract (P = 0.027).
As in other population-based studies on Chinese, myopia was more prevalent in younger subjects. Myopia was associated with urban region, educational background, female gender, decreasing visual acuity, and nuclear cataract. If longitudinal studies confirm the association of refractive error with age, refractive surgery may achieve emmetropia only for a limited time.
Ophthalmology 10/2005; 112(10):1676-83. · 5.45 Impact Factor
