Visual conditions affecting eye growth alter diurnal levels of vitreous DOPAC.

In chicks, the diurnal patterns of retinal dopamine synthesis and release are associated with refractive development. To assess the within-day patterns of dopamine release, we assayed vitreal levels of DOPAC (3,4-dihydroxyphenylacetic acid) using high performance liquid chromatography with electrochemical detection, at 4-h intervals over 24 h in eyes with experimental manipulations that change ocular growth rates. Chicks were reared under a 12 h light/12 h dark cycle; experiments began at 12 days of age. Output was assessed by modelling using the robust variance structure of Generalized Estimating Equations. Continuous spectacle lensdefocus or form deprivation: One group experienced non-restricted visual input to both eyes and served as untreated "normal" controls. Three experimental cohorts underwent monocular visual alterations known to alter eye growth and refraction: wearing a diffuser, a negative lens or a positive lens. After one full day of device-wear, chicks were euthanized at 4-h intervals over 24 h (8 birds per time/condition). Brief hyperopic defocus: Chicks wore negative lenses for only 2 daily hours either in the morning (starting at ZT 0; n = 16) or mid-day (starting at ZT 4; n = 8) for 3 days. Vitreal DOPAC was assayed. In chicks with bilateral non-restricted vision, or with continuous defocus or form-deprivation, there was a diurnal variation in vitreal DOPAC levels for all eyes (p < 0.001 for each). In normal controls, DOPAC was highest during the daytime, lowest at night, and equivalent for both eyes. In experimental groups, regardless of whether experiencing a growth stimulatory input (diffuser; negative lens) or growth inhibitory input (positive lens), DOPAC levels were reduced compared both to fellow eyes and to those of normal controls (p < 0.001 for each). These diurnal variations in vitreous DOPAC levels under different visual conditions indicate a complexity for dopaminergic mechanisms in refractive development that requires further study.

Meta-regression with partial information on summary trial or patient characteristics.

We present a model for meta-regression in the presence of missing information on some of the study level covariates, obtaining inferences using Bayesian methods. In practice, when confronted with missing covariate data in a meta-regression, it is common to carry out a complete case or available case analysis. We propose to use the full observed data, modelling the joint density as a factorization of a meta-regression model and a conditional factorization of the density for the covariates. With the inclusion of several covariates, inter-relations between these covariates are modelled. Under this joint likelihood-based approach, it is shown that the lesser assumption of the covariates being Missing At Random is imposed, instead of the more usual Missing Completely At Random (MCAR) assumption. The model is easily programmable in WinBUGS, and we examine, through the analysis of two real data sets, sensitivity and robustness of results to the MCAR assumption.

Vision related quality of life in multiple sclerosis: correlation with new measures of low and high contrast letter acuity.

OBJECTIVE: To examine the relation between low contrast letter acuity, a new visual function test for multiple sclerosis (MS) trials, and vision targeted health related quality of life (HRQOL). METHODS: Patients in this cross sectional study were part of an ongoing investigation of visual function in MS. Patients were tested binocularly using low contrast letter acuity and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA) charts. The 25 Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25), 10 Item Neuro-Ophthalmic Supplement to the NEI-VFQ-25, Impact of Visual Impairment Scale and Short Form 36 Health Survey (SF-36) were administered. RESULTS: Among 167 patients, mean age was 48 (10) years, with median Expanded Disability Status Scale (EDSS) 2.0 (range 1.0-7.5), and median binocular Snellen acuity equivalent (ETDRS charts) 20/16 (range 20/12.5 to 20/100). Reductions in vision specific HRQOL were associated with lower (worse) scores for low contrast letter acuity and VA (p<0.001, linear regression, accounting for age). Two line differences in visual function were associated, on average, with >4 point (6.7-10.9 point) worsening in the NEI-VFQ-25 composite score, reductions that are considered clinically meaningful. Scores for the 10 Item Neuro-Ophthalmic Supplement to the NEI-VFQ-25 also correlated well with visual function. Associations between reduced low contrast acuity and worse vision targeted HRQOL remained significant in models accounting for high contrast VA, EDSS and history of acute optic neuritis. CONCLUSIONS: Low contrast letter acuity scores correlate well with HRQOL in MS. Two line differences in scores for low contrast acuity and VA reflect clinically meaningful differences in vision targeted HRQOL. Low contrast acuity testing provides information on patient reported aspects of vision, supporting use of these measures in MS clinical trials.

Association of dietary protein intake and coffee consumption with serum homocysteine concentrations in an older population.

BACKGROUND: Elevated blood concentrations of total homocysteine (tHcy) have been implicated in the pathogenesis of atherosclerotic cardiovascular disease. Previous studies identified suboptimal nutritional status and dietary intake of folate, vitamin B-6, and vitamin B-12 as determinants of elevated tHcy. OBJECTIVE: We identified other nutritional factors associated with tHcy in 260 retired schoolteachers in the Baltimore metropolitan area. DESIGN: We performed observational analyses of baseline and 2-4-mo follow-up data collected in a study designed to test the feasibility of conducting a large-scale clinical trial of vitamin supplements by mail. The study population consisted of 151 women and 109 men with a median age of 64 y. At baseline, each participant completed a food-frequency questionnaire. At follow-up, fasting serum tHcy was measured. RESULTS: In multivariable linear regression and generalized linear models, there was an independent, inverse dose-response relation between dietary protein and In tHcy (P = 0.002) and a positive, significant dose-response relation between coffee consumption and In tHcy (P for trend = 0.01). Other significant predictors of In tHcy were creatinine (positive; P = 0.0001) and prestudy use of supplemental B vitamins (inverse; P = 0.03). In stratified analyses restricted to persons receiving standard multivitamin therapy, the association of 1n tHcy with dietary protein and coffee persisted. CONCLUSIONS: These results support the hypothesis that increased protein intake and decreased coffee consumption may reduce tHcy and potentially prevent atherosclerotic cardiovascular disease and other disease outcomes.

Idiopathic intracranial hypertension: relation of age and obesity in children.

The relation between obesity and age in children with idiopathic intracranial hypertension (pseudotumor cerebri) has remained uncertain. The authors reviewed the records of 45 consecutive children with newly diagnosed idiopathic intracranial hypertension seen at two medical centers. Forty-three percent of patients aged 3 to 11 years were obese, whereas 81% of those in the 12- to 14-year age group and 91% of those in the 15- to 17-year age group met criteria for obesity (p = 0.01). Younger children with idiopathic intracranial hypertension are less likely to be obese than are older children or adults.

Psychophysical evidence for rod vulnerability in age-related macular degeneration.

PURPOSE: To determine whether there is rod system dysfunction in the central retina of patients with age-related macular degeneration (AMD). METHODS: Dark-adapted sensitivity (500-nm stimulus) and light-adapted sensitivity (600 nm) were measured psychophysically at 52 loci in the central 38 degrees (diameter) of retina in 80 patients with AMD, and results were compared with those from older adult normal controls. All dark-adapted data were corrected for preretinal absorption. RESULTS: Mean field dark-adapted sensitivity was significantly lower in AMD patients as a group than in normal subjects. Within the AMD group were subsets of patients with normal mean dark- and light-adapted sensitivities; reduced dark-adapted sensitivities without detectable light-adapted losses; both types of losses; and, least commonly, only light-adapted losses. Regional retinal analyses of the dark-adapted deficit indicated the greatest severity was 2 degrees to 4 degrees or approximately 1 mm from the fovea, and the deficit decreased with increasing eccentricity. CONCLUSIONS: These psychophysical results are consistent with histopathologic findings of a selective vulnerability for parafoveal rod photoreceptors in AMD. The different patterns of rod and cone system losses among patients at similar clinical stages reinforces the notion that AMD is a group of disorders with underlying heterogeneity of mechanism of visual loss. Dark-adapted macula-wide testing may be a useful complement to the more traditional outcome measures of fundus pathology and foveal cone-based psychophysics in future AMD trials.

Foveolar choroidal blood flow in age-related macular degeneration.

PURPOSE: To compare measurements of the foveolar choroidal blood circulation in subjects with nonexudative, age-related macular degeneration (AMD) with those of control subjects. METHODS: Laser Doppler flowmetry was used to assess relative choroidal blood velocity (ChBVel), volume (ChBVol), and flow (ChBFlow) in the center of the fovea. Measurements were obtained in 20 eyes of 20 subjects with 10 or more large drusen, visual acuity of 20/32 or better, and no evidence of choroidal neovascularization. Findings obtained in these subjects were compared with those of 10 eyes of 10 age- and blood pressure-matched control subjects with no large drusen. Foveolar choroidal blood flow measurements were obtained by asking the study participants to fixate on a probing laser beam. RESULTS: No significant differences in average age, blood pressure, or intraocular pressure were observed between subjects with AMD and control subjects. In subjects with AMD, average ChBVol was 0.24 +/- 0.08 (+/- 1 SD) arbitrary units (AU); this value was 33% lower than that of control subjects (0.36 +/- 0.11 AU; two-tailed, independent Student's t-test, P = 0.005). Average ChBVel, conversely, was not significantly different from normal (0.44 +/- 0.07 AU) in subjects with AMD (0.44 +/- 0.10 AU). Average ChBFlow in subjects with AMD (8.7 +/- 3.1 AU) was 37% lower than that of control subjects (13.7 +/- 3.5 AU) (P = 0.0005). Average blood flow pulsatility was 6% higher in subjects with AMD (0.71 +/- 0.15) than in control subjects (0.66 +/- 0.14), but this difference was not statistically significant (P = 0.42). CONCLUSIONS: Average ChBFlow in the nonexudative stages of AMD is lower than that of age-matched controls, and the effect is caused mainly by a decrease in ChBVol. Further studies are needed to elucidate whether decreased ChBFlow plays a role in the development of choroidal neovascularization, and whether ChBFlow measurements may help identify subjects with AMD at risk for developing choroidal neovascularization.

Macular pigment and lutein supplementation in retinitis pigmentosa and Usher syndrome.

PURPOSE: To determine macular pigment (MP) in patients with inherited retinal degeneration and the response of MP and vision to supplementation of lutein. METHODS: Patients with retinitis pigmentosa (RP) or Usher syndrome and normal subjects had MP optical density profiles measured with heterochromatic flicker photometry. Serum carotenoids, visual acuity, foveal sensitivity, and retinal thickness (by optical coherence tomography [OCT]) were quantified. The effects on MP and central vision of 6 months of lutein supplementation at 20 mg/d were determined. RESULTS: MP density in the patients as a group did not differ from normal. Among patients with lower MP, there was a higher percentage of females, smokers, and light-colored irides. Disease expression tended to be more severe in patients with lower MP. Inner retinal thickness by OCT correlated positively with MP density in the patients. After supplementation, all participants showed an increase in serum lutein. Only approximately half the patients showed a statistically significant increase in MP. Retinal nonresponders had slightly greater disease severity but were otherwise not distinguishable from responders. Central vision was unchanged after supplementation. CONCLUSIONS: Factors previously associated with lower or higher MP density in normal subjects showed similar associations in RP and Usher syndrome. In addition, MP in patients may be affected by stage of retinal disease, especially that leading to abnormal foveal architecture. MP could be augmented by supplemental lutein in many but not all patients. There was no change in central vision after 6 months of lutein supplementation, but long-term influences on the natural history of these retinal degenerations require further study.

Reproducibility of HLA-A, B, and DR typing using peripheral blood samples: results of retyping in the collaborative corneal transplantation studies. Collaborative Corneal Transplantation Studies Group (corrected)

Recipients enrolled in the Collaborative Corneal Transplantation Studies were retyped as part of a quality assurance program. Because the observed percentage of HLA-DR homozygosity on original typing was more than twice as high as expected from CCTS allele frequencies, the sample selected for retyping was heavily weighted with patients whose original typing identified fewer than two DR antigens. Retyping was performed in a different laboratory from the laboratory performing the original typing. For the 129 patients who were retyped, agreement between the original and retyping laboratories was 88% for HLA-A, 79% for HLA-B, and 55% for HLA-DR. When criteria was relaxed to consider only discrepancies involving readily identifiable antigens, the agreement improved to 95% for HLA-A, 91% for HLA-B, and 59% for HLA-DR. Identification of a second HLA-DR antigen on retyping when only one DR antigen had been identified on original typing was by far the most common form of disagreement. There were no significant differences in the amount of disagreement among the laboratories. Of special interest is that 50% of the discrepancies involved DR3, DR5, and/or DR6, which have structural similarities. Based on the results of the project, we recommend: (1) replicate testing for all DR typing; and (2) retyping using a second source of antiserum for all subjects having DR blanks.

A model of the incidence and consequences of choroidal neovascularization secondary to age-related macular degeneration. Comparative effects of current treatment and potential prophylaxis on visual outcomes in high-risk patients.

OBJECTIVE: To describe the comparative impact of current and preventive treatments on incidence of choroidal neovascularization (CNV) and severe vision loss in patients with bilateral soft drusen (BSD). DESIGN: Stochastic model. SETTING: US population. PATIENTS: Prevalence cohort of white patients 43 years or older with BSD. INTERVENTIONS: Application of prophylaxis of 10% to 50% efficacy to 1 or both eyes of patients with BSD, application of laser photocoagulation to eligible CNV lesions, or both. MAIN OUTCOME MEASURES: Proportion of patients with BSD after 10 years with unilateral and bilateral CNV and resultant unilateral and bilateral vision loss to visual acuity of 20/200 or worse. RESULTS: The natural history of patients with BSD generated by the model shows that 12.40% of these patients develop either unilateral or bilateral CNV within 10 years of their entry into the BSD prevalence cohort. Bilateral disease occurs in 3.86% of patients with BSD within 10 years. The proportion of patients with BSD becoming legally blind from CNV within 10 years is 2.54% if no treatment is performed. Current laser treatment for CNV decreases the proportion with legal blindness within 10 years to 2.24%. The addition of a preventive treatment of 10% efficacy applied bilaterally to the current laser treatment regimen decreases the proportion with legal blindness to 1.86%; a 25% effective preventive treatment decreases it to 1.34%. Comparatively, preventive treatment of 10% and 25% efficacy given to the fellow eye only after the first eye has developed CNV decreases the proportion of legally blind patients at 10 years only to 2.06% and 1.77%, respectively. All outcomes vary with sex and age at entry into the BSD cohort. CONCLUSIONS: Patients with BSD face a 12.40% risk of developing CNV within 10 years. The addition of even a modest (10% effective) bilateral preventive treatment to the current regimen for CNV would more than double the prevention of legal blindness in the BSD population relative to current laser treatment; a preventive treatment of 33% efficacy more than halves the rate of legal blindness caused by CNV. Preventive treatment given to the fellow eye only after the first develops CNV has substantially less impact.

Detecting recurrent choroidal neovascularization. Comparison of clinical examination with and without fluorescein angiography.

OBJECTIVE/DESIGN: To evaluate prospectively the ability of three retina specialists to detect recurrent choroidal neovascularization (CNV) after clinical examination alone and then with fluorescein angiography at 3 and 6 weeks and at 3, 6, 9, and 12 months after laser photocoagulation. SETTING: Single tertiary retinal referral center. PATIENTS: All patients who had laser treatment for CNV within 14 months of their study visit. One hundred thirty-seven eyes of 134 patients were evaluated during 401 visits. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive predictive value, and negative predictive value of clinical examination with biomicroscopy to detect recurrent CNV when defined as leakage on the periphery of the laser-treated area on the fluorescein angiogram. RESULTS: Ninety-seven definite or probable recurrences in 56 eyes were identified on the fluorescein angiogram. Clinical examination had a sensitivity of 59%, specificity of 94%, positive predictive value of 76%, and negative predictive value of 88%. These figures varied somewhat by underlying cause, age, time since treatment, and lesion location. Using either a reported or measured loss of vision with the results of biomicroscopy as an indication of recurrence increased the sensitivity to 77% but reduced the specificity to 81%. CONCLUSIONS: Clinical examination probably cannot replace fluorescein angiography in detecting all recurrent CNV after laser treatment. However, for follow-up visits in which recurrent CNV was not suspected on biomicroscopy, definite or questionable recurrent CNV was identified on the fluorescein angiogram only 12% of the time, while the absence of recurrent CNV using this method was confirmed 88% of the time.

Relationship of drusen and abnormalities of the retinal pigment epithelium to the prognosis of neovascular macular degeneration. The Macular Photocoagulation Study Group.

We graded macular features of 127 fellow eyes of participants in the Macular Photocoagulation Study who had an extrafoveal choroidal neovascular membrane secondary to age-related macular degeneration in the first eye and no initial evidence of the neovascular form of age-related macular degeneration in the fellow eye. Our aims were to determine the relationship of drusen characteristics and retinal pigment epithelial abnormalities to the risk of subsequent development of neovascularization in the fellow eye and the risk of subsequent development of recurrent neovascular membranes after photocoagulation in the first eye. Regression analysis demonstrated that the presence of large drusen and focal hyperpigmentation of the retinal pigment epithelium were independent risk factors for the subsequent development of neovascularization in the fellow eye (relative risk, 2.4 and 2.5, respectively). Only 10% of eyes with no large drusen or any retinal pigment epithelial hyperpigmentation compared with 58% of eyes with both large drusen and retinal pigment epithelial hyperpigmentation developed neovascularization in the fellow eye within 5 years. Using multivariate Cox regression analysis, we noted that the risk of developing recurrent neovascular membranes in the first eye was significantly increased when large drusen (relative risk, 2.8) were noted in the fellow eye at the time of laser treatment in the first eye. Fundus features in the fellow eye appear to help identify patients at high risk of developing visual loss from recurrent neovascular membranes following laser treatment in the first eye and from development of a neovascular membrane in the fellow eye.

Laser burn intensity and the risk for choroidal neovascularization in the CNVPT Fellow Eye Study.

OBJECTIVE: To explore the relationship between laser burn intensity and the subsequent risk for development of choroidal neovascularization (CNV) in eyes assigned to the treatment group of the Fellow Eye Study (FES) of the Choroidal Neovascularization Prevention Trial (CNVPT), using computerized methods for laser burn quantitation, and to examine the association between laser burn intensity and (1) drusen reduction and (2) visual acuity. METHODS: Color fundus images before and immediately after laser treatment in the CNVPT FES were available for 53 of 59 eyes. Prelaser and postlaser treatment images were analyzed using custom-developed computer software, allowing for laser burn identification and quantitation. As measures of laser burn intensity, we derived integrated burn rating (IBR) (the integral of the normalized intensity difference divided by the burn pixels), and the maximum burn intensity (MAX). We identified CNV using fluorescein angiography. A Cox proportional hazards model was fit to the time to development of CNV. Baseline and 6-month color photographs were used to determine reduction in drusen. Visual acuity was measured using a standardized protocol. RESULTS: The IBR and MAX spanned 4.5 logarithm units. After adjusting for smoking history and predominant drusen size, the risk ratio for CNV per logarithm unit of increasing laser burn intensity for each measure was 2.0 (P =.05) for MAX and 1.7 (P =.07) for IBR. When patients were divided into high- and low-intensity treatment groups of equal size, the high-intensity group had more drusen reduction (57% vs 32%; P =.14). There was no effect of laser intensity on change in visual acuity at 6 months. CONCLUSION: Higher-intensity prophylactic laser applications appear to be associated with a greater risk for development of CNV and with more extensive drusen reduction.

Interval between onset of mild nonproliferative and proliferative retinopathy in type I diabetes.

OBJECTIVE: To describe the interval between first appearance of mild nonproliferative diabetic retinopathy (NPDR) and first appearance of neovascularization (NV) in type I diabetes. SETTING: A longitudinal study of 269 patients followed up annually. PARTICIPANTS: Participants had insulin-dependent diabetes and were free of proliferative diabetic retinopathy in both eyes at the baseline visit. MAIN OUTCOME MEASURE: Stereoscopic color fundus photographs of each eye at each study visit, graded for features of retinopathy. RESULTS: Among the 305 eyes for which the duration of diabetes at the first appearance of mild NPDR could be determined, NV developed in 28 by the end of the study. Survival analysis showed that the later the onset of mild NPDR was, the shorter the time from onset of mild NPDR to onset of NV (relative hazard for each additional year to onset of mild NPDR, 1.22; 95% confidence interval, 1.10-1.35). Adjustment for systolic and diastolic blood pressure, proteinuria, and glycosylated hemoglobin (Hgb A10) levels did not change the relative hazard estimate for onset of mild NPDR. Higher levels of Hgb A10 were associated with a shorter time from onset of mild NPDR to onset of NV (relative hazard, 1.26; 95% confidence interval, 1.05-1.51 [after adjusting for time at onset of mild NPDR]), as were higher levels of diastolic blood pressure, although not significantly (relative hazard for 10-mm Hg increase in diastolic blood pressure, 1.52; 95% confidence interval, 0.82-2.83 [adjusting for onset of mild NPDR, Hgb A10 level, systolic blood pressure, and proteinuria]). Neither proteinuria nor systolic blood pressure had an effect on time from onset of mild NPDR to onset of NV, after adjustment for time at onset of mild NPDR, Hgb A10 level, and diastolic blood pressure. CONCLUSION: Later onset of mild NPDR is not necessarily associated with delayed development of NV in patients with type I diabetes. Caution must therefore be used in assessing the value of interventions that delay the onset of mild NPDR without evidence of delayed onset of NV.

Efficacy of ofloxacin vs cefazolin and tobramycin in the therapy for bacterial keratitis. Report from the Bacterial Keratitis Study Research Group.

PURPOSE: To compare ofloxacin solution with a combination of fortified antibiotic cefazolin sodium and tobramycin sulfate solutions in the treatment of bacterial keratitis. METHODS: Patients under care at any one of 28 participating clinical centers who had an eye with suspected bacterial keratitis were randomly allocated in a double-masked manner to treatment with 0.3% ofloxacin solution or a combination of the fortified antibiotics (1.5% tobramycin and 10.0% cefazolin solutions). MAIN OUTCOME MEASURES: Time to healing defined as complete re-epithelization, accompanied by a nonprogressive stromal infiltrate for two consecutive visits. Secondary outcome measures included patient symptoms and signs of infection and adverse reactions to study medications. Only patients with a positive bacterial corneal culture were included in most analyses. RESULTS: A positive bacterial corneal culture was obtained in 140 (56%) of the 248 enrolled patients. The time to healing was similar among the 73 patients receiving ofloxacin and the 67 patients receiving fortified antibiotics (P = .70). By 7 days after study entry, the keratitis in 37% of the ofloxacin group and 38% of the fortified antibiotics group had healed. By 28 days, keratitis in 89% of the ofloxacin group and 86% of the fortified antibiotics group had healed. Two patients receiving ofloxacin and one receiving fortified antibiotics discontinued study medication because of lack of efficacy. Patients receiving ofloxacin reported substantially less burning and stinging on instillation than the patients receiving fortified antibiotics (P < .001). Five of six patients among the 140 with positive bacterial cultures who had study medications discontinued because of ocular side effects were in the fortified antibiotics group; an additional three patients, all in the fortified antibiotics group, among the remaining 108 receiving study medications had ocular side effects. CONCLUSIONS: The efficacy of ofloxacin solution in treating bacterial keratitis is equivalent to that of the fortified cefazolin and tobramycin solutions. The reduced frequency of ocular toxic effects and the relative ease of preparation of ofloxacin are additional considerations.

Laser treatment for choroidal neovascularization outside randomized clinical trials.

This study was undertaken to determine whether the treatment benefit reported in randomized trials for patients with extrafoveal choroidal neovascular membranes (NVMs) secondary to age-related macular degeneration (AMD) or the ocular histoplasmosis syndrome (OHS) can be duplicated in other clinical settings. The visual results and recurrence rates in treated extrafoveal NVMs of 70 patients with AMD and 21 patients with OHS were similar to those reported by the Macular Photocoagulation Study Group, in which all treated patients received argon blue-green laser photocoagulation after the administration of retrobulbar anesthesia. In this study, 78% (71/90) of the patients were treated with krypton laser and only 35% (32/90) had retrobulbar anesthesia. These results suggest, but do not prove, that the wavelength of the laser used or the administration of retrobulbar anesthesia may not be critical variables in determining the success of treatment in patients with extra-foveal NVMs.

Assessment of visual function in patients with age-related macular degeneration and low visual acuity.

The visual function of 100 eyes with low visual acuity of 100 patients with age-related macular degeneration was examined using measurements of visual acuity, peak contrast sensitivity, and the ability to read, to tell time, and to distinguish colors, products, and facial expressions. Visual acuity and peak contrast sensitivity were correlated (r = .62); however, a range of peak contrast sensitivities was observed at each level of acuity. When considered individually, visual acuity and peak contrast sensitivity were related to the ability to perform each of the tasks. When multivariate methods were applied, both visual acuity and peak contrast sensitivity contributed independently to the ability to read and tell time. Among patients with the same contrast sensitivity, visual acuity had little or no relationship to the ability to identify colors, products, and faces.

Functional vision in patients with neovascular maculopathy and poor visual acuity.

Central visual function is characteristically reported as Snellen acuity at distance and near. We performed functional tests in a group of patients with visual acuity of 20/100 or worse due to macular disease to determine whether there was a relationship between Snellen acuity and functional performance among these patients with poor visual acuity. Our tests of functional performance included currency discrimination, color recognition, reading a clock, and reading large print. Our results suggest that there is a correlation between Snellen acuity and functional vision, even among patients with poor visual acuity. Hence, therapeutic efforts to keep patients' visual acuity at 20/200 rather than 20/400, for example, appears to be justifiable in that better acuity levels seem to be associated with improved functional performance.

Subfoveal choroidal neovascular membranes in age-related macular degeneration. Visual prognosis in eyes with relatively good initial visual acuity.

We determined the visual prognosis of 94 eyes in 92 patients having age-related macular degeneration, a discrete choroidal neovascular membrane directly under the center of the foveal avascular zone (subfoveal), and an initial visual acuity of 20/100 or better. Of the patients who were reexamined 24 months following their initial presentation, 77% had lost at least four lines of vision and 64% had lost at least six lines. Estimation of visual loss using a conservative assessment procedure showed four-line visual loss in 65% of the patients and six-line loss in 50%. In general, the better the visual acuity at the initial examination, the more likely the patient was to have a smaller choroidal neovascular membrane. These results suggest that it may be reasonable to consider a randomized clinical trial of laser photocoagulation for this group of patients with a relatively poor visual prognosis.

Five-year incidence and disappearance of drusen and retinal pigment epithelial abnormalities. Waterman study.

PURPOSE: To obtain 5-year longitudinal data on age-related macular degeneration (AMD) that might be useful for disease prognosis, public health planning, and clinical trial development. PATIENTS AND METHODS: Baseline (1985) and 5-year follow-up (1990) fundus photographs of 483 watermen over 30 years of age who participated in a cohort study conducted on the eastern shore of Maryland were graded independently in a reliable, standardized fashion. Eyes in which AMD appeared or disappeared also were graded in a side-by-side fashion. RESULTS: Development of definite choroidal neovascularization and/or disciform scarring occurred in one of 50 participants over 70 years of age, specifically one of 15 participants over 70 years of age with AMD-3 (defined as large or confluent drusen focal hyperpigmentation of the retinal pigment epithelium [RPE], and/or nongeographic atrophy of the RPE). Appearance of large drusen, focal hyperpigmentation, or AMD-3 was age related, occurring in 5%, 1%, and 7%, respectively, of participants aged 50 to 59 years; 17%, 3%, and 14%, respectively, of participants aged 60 to 69 years; and 17%, 9%, and 26%, respectively, of participants aged 70 years or more. Disappearance of large drusen, hyperpigmentation, or AMD-3 occurred in 16 (34%) of 47 participants, 11 (58%) of 19 participants, and 17 (28%) of 61 participants, respectively, who had each feature photographically present in 1985. Among the 47 eyes identified in which AMD-3 developed by independent gradings, 38 cases of AMD-3 (81%) were confirmed on side-by-side grading. Among the 16 eyes identified as having AMD-3 that disappeared, nine disappearances (56%) were confirmed. Borderline differences in appearance of pigment, drusen size, drusen location, or photographic quality may have accounted for disappearance in seven cases (44%). CONCLUSIONS: Prospective studies on the nonneovascular features of AMD (including large drusen and abnormalities of the RPE) must account for the appearance and disappearance of these features and support the idea that side-by-side gradings can complement independent gradings identifying appearance or disappearance of features of AMD.