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PurposeTo investigate changes in limbal basal epithelial cell density in eyes with limbal stem cell deficiency (LSCD) using in vivo confocal laser scanning microscopy.DesignRetrospective observational comparative study.MethodsA total of 43 eyes of 30 patients diagnosed with LSCD were included in the study. Ten eyes from normal subjects were included as control. Confocal imaging of the central cornea, and the superior, nasal, inferior and temporal limbus were collected using the Heidelberg Retina Tomograph III Rostock Corneal Module. Basal cell density in all locations was measured by 2 independent observers.ResultsThe mean basal cell density of the normal group was 9264 ± 598 cells/mm(2) in the cornea and 7120 ± 362 cells/mm(2) in the limbus. In the LSCD group, the mean basal cell density in the cornea decreased 31.0% (6389 ± 1820 cells/mm(2), P < .001) and in the limbus decreased 23.6% (5440 ± 1123 cells/mm(2), P < .001) compared to that in the control. There was a trend of basal cell density decline in more advanced stages of LSCD. The basal cell density declined in the unaffected regions at a similar degree as that in the affected region in sectoral LSCD (P > .05). The basal cell diameter increased by 24.6% in the cornea (14.7 μm) and by 15.7% in the limbus (15.5 μm) compared to the control.ConclusionsBasal cell density in both central cornea and limbus decreases in LSCD. Limbal stem cells (LSCs) are affected globally and basal cell density could be used as a parameter to measure LSC function at the early stages of the disease process.

PurposeTo determine the retinal nerve fiber layer (RNFL) thickness at which visual field (VF) damage becomes detectable and associated with structural loss.DesignRetrospective cross-sectional study.MethodsEighty-seven healthy and 108 glaucoma subjects (1 eye per subject) were recruited from an academic institution. All patients had VF examinations (Swedish Interactive Threshold Algorithm 24-2 test of the Humphrey Visual Field Analyzer 750i) and spectral-domain optical coherence tomography RNFL scans. Comparison of RNFL thickness values with VF threshold values showed a plateau of VF threshold values at high RNFL thickness values and then a sharp decrease at lower RNFL thickness values. A broken stick statistical analysis was used to estimate the tipping point at which RNFL thickness values are associated with VF defects. The slope for the association between structure and function was computed for data above and below the tipping point.ResultsThe mean RNFL thickness value that was associated with initial VF loss was 89 μm. The superior RNFL thickness value that was associated with initial corresponding inferior VF loss was 100 μm. The inferior RNFL thickness value that was associated with initial corresponding superior VF loss was 73 μm. The differences between all the slopes above and below the aforementioned tipping points were statistically significant (P < .001).ConclusionsIn open-angle glaucoma, substantial RNFL thinning or structural loss appears to be necessary before functional visual field defects become detectable.

PurposeTo investigate whether recurrence rates of ocular toxoplasmosis are higher during pregnancy in women of childbearing age.DesignRetrospective longitudinal cohort study.MethodsWe reviewed medical records of all women seen at a university eye clinic (Utrecht, Netherlands) during episodes of active toxoplasmic retinochoroiditis that occurred while the women were of childbearing age (16-42 years). Each woman was sent a questionnaire requesting information regarding all pregnancies and episodes of ocular toxoplasmosis, whether or not episodes were observed at the eye clinic. Conditional fixed-effects Poisson regression was used to model incidence rate ratios of recurrence during pregnant versus nonpregnant intervals, adjusted for potential confounders, including age at time of active toxoplasmic retinochoroiditis and interval since last episode of active disease, which are known to influence risk for recurrence.ResultsQuestionnaires were returned by 50 (58%) of 86 women, 34 of whom had had 69 pregnancies during 584 person-years of study. There were 128 episodes of ocular toxoplasmosis during the study period (6 during pregnancy). First episodes of ocular toxoplasmosis occurred between ages 9.6 and 38.5 years. The youngest age at pregnancy was 16.1 years; the oldest age at childbirth was 40.9 years. The incidence-rate ratios for pregnant versus nonpregnant intervals were in the direction of lower recurrence rates during pregnancy, with point estimates of 0.54 and 0.75 under 2 different approaches, but the ratios were not significantly different from the null value (P values of 0.16 and 0.55).ConclusionsRecurrence rates of ocular toxoplasmosis are probably not higher during pregnancy, in contrast to traditional beliefs.

PurposeTo assess vision-specific quality of life (QOL), based on abbreviated surveys derived from the National Eye Institute Visual Function Questionnaire (NEI-VFQ), in a cohort of United States women who participated in the Study of Osteoporotic Fractures.DesignProspective, observational cohort study.MethodsAge-related macular degeneration (AMD) status, based on a 3-level classification (no AMD, early AMD, late AMD), and vision-specific QOL, based on abbreviated NEI-VFQ surveys, were calculated for 1674 women enrolled in the Study of Osteoporotic Fractures at 4 centers within the United States who had gradable fundus photographs at both the 10-year and 15-year follow-up visits. The associations among 5-year changes in NEI-VFQ composite scores, change in AMD status, and distance visual acuity were examined.ResultsCompared with study participants without AMD at both visits, study participants with late AMD at both visits and those who progressed from early AMD to late AMD demonstrated the greatest declines in adjusted NEI-VFQ composite scores, up to a mean decrease of 16.2 from a scale of 100. Visual acuity declines also were most prominent for patients with late AMD at both visits and for those who progressed from early AMD to late AMD. Change in visual acuity was found to correlate significantly with change in vision-specific QOL.ConclusionsThe abbreviated NEI-VFQ surveys provide reliable assessments of vision-specific QOL in AMD patients. The decline in vision-specific QOL associated with the progression of AMD is clinically meaningful.

PurposeTo test the reliability and validity of questionnaires shortened from the National Eye Institute 25-item Vision Function Questionnaire (NEI VFQ-25).DesignCross-sectional, multicenter cohort study.MethodsReliability was assessed by Cronbach alpha coefficients. Validity was evaluated by studying the association of vision-targeted quality-of-life composite scores with objective visual function measurements. A total of 5482 women between the ages of 65 and 100 years participated in the year-10 clinic visit in the Study of Osteoporotic Fractures (SOF). A total of 3631 women with complete data were included in the visual acuity (VA) and visual field (VF) analyses of the 9-item NEI VFQ (NEI VFQ-9), which is defined for those who care to drive, and a total of 5311 women with complete data were included in the VA and VF in the analyses of the 8-item NEI VFQ (NEI VFQ-8). To assess differences in prevalent eye diseases, which were ascertained for a random sample of SOF participants, 853 and 1237 women were included in the NEI VFQ-9 and the NEI VFQ-8 analyses, respectively.ResultsThe Cronbach alpha coefficient for the NEI VFQ-9 scale was 0.83, and that of the NEI VFQ-8 was 0.84. Using both questionnaires, women with VA worse than 20/40 had lower composite scores compared with those with VA of 20/40 or better (P < .001). Participants with mild, moderate, and severe binocular VF loss had lower composite scores compared with those with no binocular VF loss (P < .001). Compared with women without chronic eye diseases in both eyes, women with at least 1 chronic eye disease in at least 1 eye had lower composite scores.ConclusionsBoth questionnaires showed high reliability across items and validity with respect to clinical markers of eye disease. Future research should compare the properties of these shortened surveys with those of the NEI VFQ-25.

PurposeTo estimate the incidence of age-related macular degeneration (AMD) and the association of smoking and alcohol in a population of older women.DesignProspective cohort study.MethodsSubjects were women who attended the Study of Osteoporotic Fractures year-10 and year-15 follow-up clinic visits and had fundus photographs taken at both visits (n = 1958; 245 Black and 1713 White subjects; mean age at year 10 visit, 78.2 years). Forty-five degree stereoscopic fundus photographs were graded for AMD. Logistic regression was used to test whether risk factors were associated with incident AMD.ResultsThe overall 5-year AMD incidence was 24.1% (95% confidence interval [CI], 21.7 to 26.6) for early and 5.7% (95% CI, 4.6 to 6.8) for late. Early AMD incidence in White subjects ranged from 21.9% in those aged 74 to 79 years to 33.2% in those 80 to 84 years, but was observed at the slightly lower rate of 29.0% in subjects > or =85 years (trend P < .0001). After confounder adjustment, alcohol consumption was significantly associated with an elevated risk of incident early AMD (odds ratio [OR], 1.57; 95% CI, 1.18 to 2.11). There was an increased risk of early AMD among subjects aged 80 years or older who were smoking compared to those younger than 80 years who were not smoking (OR, 5.49; 95% CI, 1.57 to 19.20; P for interaction = .026).ConclusionsThe magnitude of the greater-than-additive effect of smoking on the age-adjusted risk of AMD reinforces recommendations to quit smoking even for older individuals.

PurposeTo explore the association between the consumption of fruits and vegetables and the presence of glaucoma.DesignCross-sectional cohort study.MethodsIn a sample of 1,155 women located in multiple centers in the United States, glaucoma specialists diagnosed glaucoma in at least one eye by assessing optic nerve head photographs and 76-point suprathreshold screening visual fields. Consumption of fruits and vegetables was assessed using the Block Food Frequency Questionnaire. The relationship between selected fruit and vegetable consumption and glaucoma was investigated using adjusted logistic regression models.ResultsAmong 1,155 women, 95 (8.2%) were diagnosed with glaucoma. In adjusted analysis, the odds of glaucoma risk were decreased by 69% (odds ratio [OR], 0.31; 95% confidence interval [CI], 0.11 to 0.91) in women who consumed at least one serving per month of green collards and kale compared with those who consumed fewer than one serving per month, by 64% (OR, 0.36; 95% CI, 0.17 to 0.77) in women who consumed more than two servings per week of carrots compared with those who consumed fewer than one serving per week, and by 47% (OR, 0.53; 95% CI, 0.29 to 0.97) in women who consumed at least one serving per week of canned or dried peaches compared with those who consumed fewer than one serving per month.ConclusionsA higher intake of certain fruits and vegetables may be associated with a decreased risk of glaucoma. More studies are needed to investigate this relationship.