PURPOSE: The purpose of this study was to compare habitual visual acuity in a sample of young children using two versions of the single Lea symbols charts with different crowding features.
METHODS: Monocular habitual visual acuity was measured in a sample of 77 young children aged between 4 and 6 years using crowded Lea symbols charts with either flanking bars separated from the central symbol by 0.5 optotype width or flanking Lea optotypes separated from the central symbol by 1.0 optotype width.
RESULTS: Mean visual acuity was higher (i.e., lower logarithm of the minimum angle of resolution) with the Lea symbols crowded using flanking optotypes, equivalent to about 1.5 optotype difference. Visual acuity measured with the two charts was significantly correlated; however, the 95% limits of agreement were larger than expected from repeatability studies using Lea symbols.
CONCLUSIONS: Lea symbols with flanking optotypes resulted in higher visual acuity than the Lea symbols with flanking bars, probably as a result of differences in the crowding effect. The two charts showed insufficient agreement, and we do not recommend their use interchangeably. We recommend using the Lea symbols with flanking bars because of the closer flanker-target separation.
DESIGN: Retrospective interventional case series.
PARTICIPANTS: Five patients with visual disturbances resulting from a benign, well-circumscribed orbital apex tumor (3 cases of cavernous hemangioma and 2 cases of schwannoma).
METHODS: Each patient treated with GKRS with a total radiation dose of 20 Gy in 4 sessions (5 Gy in each session with an isodose line of 50%) delivered to the tumor margin.
MAIN OUTCOME MEASURES: Best-corrected visual acuity, visual field changes, orbital imaging, tumor growth control, and side effects of radiation.
RESULTS: All patients demonstrated improvement in visual acuity, pupillary responses, color vision, and visual field. Tumor shrinkage was observed in all patients and remained stable until the last follow-up. No adverse events were noted during or after the radiosurgery. None of the patients experienced any radiation-related ocular morbidity.
CONCLUSIONS: From this experience, multisession GKRS seems to be an effective management strategy to treat solitary, benign, well-circumscribed orbital apex tumors.
METHODS: Observational study. Nonglaucomatous patients on NIPD underwent systemic and ocular assessment including mean arterial pressure (MAP), body weight, serum osmolarity, visual acuity, IOP measurement, and ASOCT within 2 hours both before and after NIPD. The Zhongshan Angle Assessment Program (ZAAP) was used to measure ASOCT parameters including anterior chamber depth, anterior chamber width, anterior chamber area, anterior chamber volume, lens vault, angle opening distance, trabecular-iris space area, and angle recess area. T tests and Pearson correlation tests were performed with P<0.05 considered statistically significant.
RESULTS: A total of 46 eyes from 46 patients were included in the analysis. There were statistically significant reductions in IOP (-1.8±0.6 mm Hg, P=0.003), MAP (-11.9±3.1 mm Hg, P<0.001), body weight (-0.7±2.8 kg, P<0.001), and serum osmolarity (-3.4±2.0 mOsm/L, P=0.002) after NIPD. All the ASOCT parameters did not have any statistically significant changes after NIPD. There were no statistically significant correlations between the changes in IOP, MAP, body weight, and serum osmolarity (all P>0.05).
CONCLUSIONS: NIPD results in reductions in IOP, MAP, body weight, and serum osmolarity in nonglaucomatous patients.
Methods: A new Hindi visual acuity chart was designed to logMAR specifications using Hindi optotypes experimentally selected to have similar relative legibility under equivalent spherical and cylindrical defocus. The chart calibration study was carried out in a large clinical setup in India. Participants who were literate in English and Hindi participated in the study. Visual acuity was measured with the new Hindi logMAR chart and a modified ETDRS (m-ETDRS) logMAR chart. The method of presentation was randomized between the charts. Repeat visual acuity was measured on a subsequent day with a second version of the Hindi logMAR chart.
Results: The Hindi logMAR chart correlated highly with the m-ETDRS logMAR chart (r2 = 0.92); however, the mean visual acuity difference (Hindi logMAR-m-ETDRS logMAR) was nearly one and half lines (0.13 logMAR, 95% confidence interval [CI] = ±0.15 logMAR). The Hindi logMAR chart also proved to be highly repeatable (r2 = 0.99; mean difference 0.005, 95% CI = ±0.04 logMAR).
Conclusion: This study reports the first standardized visual acuity chart developed in Hindi incorporating equal letter legibility and logMAR chart design features. The Hindi logMAR visual acuity chart provides a valid and repeatable tool for the measurement of visual acuity in native Hindi language speakers. Future use of the new Hindi chart should incorporate an increase in optotype size of 0.13 logMAR.
METHODS: A 45-year-old man who had undergone LASIK 5 years previously presented with blurred distance vision. Unaided vision in the right eye was 20/329-2) and 20/20 in the left eye. He enrolled for NeuroVision treatment (NeuroVision Pte Ltd, Singapore), a computer-based interface in which a repetitive set of visual excerises is performed for 10 to 12 weeks.
RESULTS: After 35 sessions, unaided visual acuity in the right eye was 20/16(-3) and 20/20(-1) in the left eye, representing 2.8 lines of improvement in the right eye and 1.6 lines in the left eye.
CONCLUSIONS: NeuroVision, a noninvasive treatment based on the concept of perceptual learning, is a benefit in cases in which surgical enhancement is not recommended.
METHODS: Multi-centre retrospective cohort study of RP patients at initial presentation. Disease severity was scored using ellipsoid zone (EZ) width on SD-OCT and logistic regression used to determine risk factors for advanced disease at presentation.
RESULTS: A total of 146 unrelated RP patients were included. Median age at onset and presentation was 40.5 (range 1-74) and 50.1 (range 3.9-81.8), respectively. Severe disease (<5° of remaining EZ width) was present in 28.1% of cases at presentation. Patients with family history of RP had greater odds of severe disease (OR 3.29, 95% CI 1.56, 6.95; p = 0.002), while male gender, race, age, syndromic features, and socioeconomic status did not. Patients with affected siblings (median EZ width 6.2°; p = 0.01), but not affected parents (median EZ width 9.4°; p = 0.99), presented with severe EZ loss compared to patients without family history (median EZ width 13.1°). Patients with affected siblings had delayed presentation (≥5 years; OR 5.76, 95% CI 1.817, 18.262; p = 0.003) compared to patients without family history.
CONCLUSIONS: Family history influences the stage of disease at which RP patients initially seek ophthalmology review. This has implications for patient counselling and the number of patients who may benefit from future therapies.
METHODS: Both eyes of patients with myopic MNV diagnosed with fluorescein angiography (FA), SD OCT and OCTA were assessed by unmasked investigators. The images were deidentified and randomised before graded by masked investigators, who determined the presence of active myopic MNV by using SD OCT together with OCTA without FA and by FA alone, respectively. The findings of masked investigators were compared with unmasked investigators.
RESULTS: 213 eyes of 110 patients comprising 499 imaging episodes were eligible for grading. For diagnosing new-onset myopic MNV without FA, combined use of SD OCT and OCTA had a sensitivity of 0.94, specificity of 0.84 and area under the curve (AUC) of 0.92. FA had a sensitivity of 0.52 (p<0.01), specificity of 0.80 (p=0.38) and AUC of 0.66 (p<0.01). For recurrent myopic MNV, the combination of SD OCT and OCTA had a sensitivity of 0.98, specificity of 0.78 and AUC of 0.88. FA had a sensitivity of 0.50 (p=0.04), specificity of 0.76 (p=0.85) and AUC of 0.63 (p=0.01). Myopic traction maculopathy was more frequently associated with recurrent myopic MNV (p<0.01).
CONCLUSION: SD OCT with dense volumetric scan was highly sensitive for diagnosing myopic MNV. The addition of OCTA improved the diagnostic specificity without FA. Monitoring of the longitudinal changes on SD OCT and judicious use of FA is a reliable surveillance strategy for myopic MNV.
METHODS: This was a cross-sectional observational study on patients with Type II diabetes mellitus from October 2020 to May 2021. Data collected include systolic/diastolic blood pressure, visual acuity, glycated hemoglobin, and central macular thickness. Diabetic retinopathy severity was categorized using the Early Treatment Diabetic Retinopathy Study classification. Photoplethysmography signals were acquired using pulse-oximeter modules (OEM-60; Dolphin Medical, Inc) measured for 90 seconds at 275 Hz sampling rate and 16-bit resolution, which records photoplethysmography fitness index, vascular risk prediction index, and vascular age.
RESULTS: One hundred and forty-one patients were equally distributed into six DR categories. Mean age was 58.8 ± 9.9 years, with female-to-male ratio of 1.27. There were significant differences in mean systolic (125.5 ± 10.0 mmHg, P = 0.007) and diastolic blood pressure (80.0 ± 8.8 mmHg), mean glycated hemoglobin (7.6 ± 1.9%, P = 0.005), median log unit of minimal angle of resolution (0.3, interquartile range: 0.2-0.5, P < 0.001), and central macular thickness ( P = 0.003) across DR severity. Significant differences were also seen in photoplethysmography fitness index ( P = 0.001), vascular risk prediction index ( P < 0.001), and vascular age ( P = 0.001), with poorer values in severe compared with mild/moderate DR. After adjusting for age, blood pressure, and glycated hemoglobin, photoplethysmography fitness reduces by 3.3% (regression coefficient, b = -3.27, P < 0.001), vascular age increases by 2.5 years ( b = 2.54, P = 0.002), and vascular risk prediction index increases by 3.1 ( b = 3.08, P < 0.001) with every DR worsening.
CONCLUSION: More severe DR stages were associated with poorer photoplethysmography vascular markers.
METHODS: This prospective clinical study included consecutive Asian patients with dark irides and confirmed for glaucoma. Only one eye of each patient was treated. Diode laser contact transscleral cyclophotocoagulation treatment was performed with the center of the probe placed 1.5 mm behind the limbus. About 30 pulses of 810-mm laser radiation (power, 1.8 to 2.0 W; duration, 0.3 to 0.5 second) were applied around the eye. Patients were examined at fixed postoperative intervals. Intraocular pressure levels and postoperative complications were recorded. The relation between patient and disease characteristics, total laser energy delivered, and intraocular pressure effects were analyzed.
RESULTS: Thirty-three patients were studied, with a mean follow-up period of 9.4 months. An average 56% of patients showed a 30% or greater drop in intraocular pressure. About 38% of patients achieved sustained intraocular pressure lowering to below 22 mm Hg at 18 months. Complications were few and included transient hypotony and iritis.
CONCLUSIONS: In Asian patients with refractory glaucoma or painful glaucomatous eyes with poor visual acuity (defined for this study as worse than 20/200), low-energy-setting diode laser contact transscleral cyclophotocoagulation by means of the glass ball probe is relatively effective and safe.
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.