METHODS: Case report.
RESULTS: A 22-year-old female patient presented with a long-standing history of reduced visual acuity in her right eye. She has generalized redundant skin, downslanting of palpebral fissures, and long philtrum. Ophthalmic examination showed ptosis in her right eye and visual acuity of 20/2000 in the right eye and 20/30p in the left eye. Funduscopic examination showed a round macular scar lesion in the right eye macula and a chorioretinal scar superonasally in the left eye. Multimodal imaging showed macular atrophy in the right eye with speckled hypoautofluorescence of the described lesions. Genetic testing showed a homozygous splice acceptor variant of the ATP6V0A2 gene.
CONCLUSION: The natural history of the presented pigmentary lesions is not known, and further follow-up is needed to assess any progressive nature. Our case adds to the variability of ophthalmic manifestations reported in autosomal recessive cutis laxa type 2A and, therefore, to the importance of regular ophthalmic surveillance in patients with cutis laxa.
METHODS: We measured psychophysical contrast thresholds in one eye of 16 control subjects and 19 patients aged 67.8 ± 5.65 and 71.9 ± 7.15, respectively, (mean ± SD). Patients ranged in disease severity from suspects to severe glaucoma. We used the 17-region FDT-perimeter C20-threshold program and a custom 9-region test (R9) with similar visual field coverage. The R9 stimuli scaled their spatial frequencies with eccentricity and were modulated at lower temporal frequencies than C20 and thus did not display a clear spatial frequency-doubling (FD) appearance. Based on the overlapping areas of the stimuli, we transformed the C20 results to 9 measures for direct comparison with R9. We also compared mfVEP-based and psychophysical contrast thresholds in 26 younger (26.6 ± 7.3 y, mean ± SD) and 20 older normal control subjects (66.5 ± 7.3 y) control subjects using the R9 stimuli.
RESULTS: The best intraclass correlations between R9/C20 thresholds were for the central and outer regions: 0.82 ± 0.05 (mean ± SD, p ≤ 0.0001). The areas under receiver operator characteristic plots for C20 and R9 were as high as 0.99 ± 0.012 (mean ± SE). Canonical correlation analysis (CCA) showed significant correlation (r = 0.638, p = 0.029) with 1 dimension of the C20 and R9 data, suggesting that the lower and higher temporal frequency tests probed the same neural mechanism(s). Low signal quality made the contrast-threshold mfVEPs non-viable. The resulting mfVEP thresholds were limited by noise to artificially high contrasts, which unlike the psychophysical versions, were not correlated with age.
CONCLUSION: The lower temporal frequency R9 stimuli had similar diagnostic power to the FDT-C20 stimuli. CCA indicated the both stimuli drove similar neural mechanisms, possibly suggesting no advantage of FD stimuli for mfVEPs. Given that the contrast-threshold mfVEPs were non-viable, we used the present and published results to make recommendations for future mfVEP tests.
PURPOSE: This study evaluated differences of TPC and TNF-α concentrations in tears at different severity of NPDR among participants with diabetes in comparison with normal participants.
METHODS: A total of 75 participants were categorized based on Early Treatment for Diabetic Retinopathy Study scale, with 15 participants representing each group, namely, normal, diabetes without retinopathy, mild NPDR, moderate NPDR, and severe NPDR. All participants were screened using McMonnies questionnaire. Refraction was conducted subjectively. Visual acuity was measured using a LogMAR chart. Twenty-five microliters of basal tears was collected using glass capillary tubes. Total protein concentration and TNF-α concentrations were determined using Bradford assay and enzyme-linked immunosorbent assay, respectively.
RESULTS: Mean ± SD age of participants (n = 75) was 57.88 ± 4.71 years, and participants scored equally in McMonnies questionnaire (P = .90). Mean visual acuity was significantly different in severe NPDR (P = .003). Mean tear TPC was significantly lower, and mean tear TNF-α concentration was significantly higher in moderate and severe NPDR (P < .001). Mean ± SD tear TPC and TNF-α concentrations for normal were 7.10 ± 1.53 and 1.39 ± 0.24 pg/mL; for diabetes without retinopathy, 6.37 ± 1.65 and 1.53 ± 0.27 pg/mL; for mild NPDR, 6.32 ± 2.05 and 1.60 ± 0.21 pg/mL; for moderate NPDR, 3.88 ± 1.38 and 1.99 ± 0.05 pg/mL; and for severe NPDR, 3.64 ± 1.26 and 2.21 ± 0.04 pg/mL, respectively. Tear TPC and TNF-α concentrations were significantly correlated (r = -0.50, P < .0001). Visual acuity was significantly correlated with tear TPC (r = -0.236, P = .04) and TNF-α concentrations (r = 0.432, P < .0001).
CONCLUSIONS: This cross-sectional study identified differences in tear TPC and TNF-α concentrations with increasing severity of NPDR.
METHODS: This was a cross-sectional study. 1332 participants aged ≥ 55 years were selected by random sampling from the parliamentary electoral register. Only 1274 participants completed the frailty assessment and 1278 participants completed the contrast sensitivity assessment. Impaired vision was defined as a Snellen visual acuity of worse than 6/12 in the better eye. Poor contrast sensitivity was defined as a score on the Pelli Robson chart of lower than 1.65. Frailty was defined with the Fried's phenotype criteria. Inter-group comparisons were determined with the independent T-test for continuous variables and the Pearson's Chi-squared test for categorical variables. The odds ratio (OR) with 95% confidence interval (CI) was used to evaluate the cross-sectional association between frailty and visual function.
RESULTS: The mean age of participants was 68.8 ± 7.5 years, of which 58.1% (774) were women. Impaired vision and poor contrast sensitivity were present in 187 (14%) and 271 (21.2%) subjects respectively. 73 (5.8%) individuals were classified as frail, 1161 (91.0.%) pre-frail, and 40 (2.8%) non-frail. There was no significant difference in frailty phenotypes between those with good and impaired vision (p = 0.241). Fried's component of handgrip strength, gait speed and exhaustion were significantly better in those with good visual function (p
DESIGN: Artificial intelligence (neural network) study.
METHODS: We assessed 1400 OCT scans of patients with neovascular AMD. Fifteen physical features for each eligible OCT, as well as patient age, were used as input data and corresponding recorded visual acuity as the target data to train, validate, and test a supervised neural network. We then applied this network to model the impact on acuity of defined OCT changes in subretinal fluid, subretinal hyperreflective material, and loss of external limiting membrane (ELM) integrity.
RESULTS: A total of 1210 eligible OCT scans were analyzed, resulting in 1210 data points, which were each 16-dimensional. A 10-layer feed-forward neural network with 1 hidden layer of 10 neurons was trained to predict acuity and demonstrated a root mean square error of 8.2 letters for predicted compared to actual visual acuity and a mean regression coefficient of 0.85. A virtual model using this network demonstrated the relationship of visual acuity to specific, programmed changes in OCT characteristics. When ELM is intact, there is a shallow decline in acuity with increasing subretinal fluid but a much steeper decline with equivalent increasing subretinal hyperreflective material. When ELM is not intact, all visual acuities are reduced. Increasing subretinal hyperreflective material or subretinal fluid in this circumstance reduces vision further still, but with a smaller gradient than when ELM is intact.
CONCLUSIONS: The supervised machine learning neural network developed is able to generate an estimated visual acuity value from OCT images in a population of patients with AMD. These findings should be of clinical and research interest in macular degeneration, for example in estimating visual prognosis or highlighting the importance of developing treatments targeting more visually destructive pathologies.