BMI was significantly higher in the obese than in the normal-weight group (p < 0.05). The obese group exhibited significantly higher EGM thresholds than the normal-weight group on the right (p < 0.05) and left (p < 0.05) posterior tongue. In chemical taste tests, the obese group had higher thresholds for sweet, salty, sour, and bitter tastes than the normal-weight group, although the difference in threshold was significant only for salty taste (p < 0.05). Smoking had an impact on taste threshold, with smokers having higher thresholds than non-smokers, with significantly higher EGM thresholds on the right anterior and posterior and the left anterior tongue (p < 0.05 each).

PurposeTo introduce a new convenient and accurate method to measure the angle kappa using ultrasound biomicroscopy (UBM) and corneal topography.MethodsData from 42 eyes (13 males and 29 females) were analyzed in this study. The angle kappa was measured using Orbscan II and calculated with UBM and corneal topography. The angle kappa of the dominant eye was compared with measurements by Orbscan II.ResultsThe mean patient age was 36.4 ± 13.8 years. The average angle kappa measured by Orbscan II was 3.98° ± 1.12°, while the average angle kappa calculated with UBM and corneal topography was 3.19° ± 1.15°. The difference in angle kappa measured by the two methods was statistically significant (p < 0.001). The two methods showed good reliability (intraclass correlation coefficient, 0.671; p < 0.001). Bland-Altman plots were used to demonstrate the agreement between the two methods.ConclusionsWe designed a new method using UBM and corneal topography to calculate the angle kappa. This method is convenient to use and allows for measurement of the angle kappa without an expensive device.

Purpose: To evaluate the clinical usefulness of a low vision aid using a virtual reality device (LVA-VR) in patients with low vision. Methods: Forty low vision patients were enrolled in this prospective study. All subjects participated in a two-session LVA-VR training course. The binocular best-corrected distance, intermediate, and near visual acuities (BCDVA, BCIVA, and BCNVA, respectively) were measured, along with contrast sensitivity and reading performance, at baseline and after 2 weeks of LVA-VR use. All subjects also provided a self-rated functional score (SFS) and completed a satisfaction questionnaire following the study. Results: Thirty-nine subjects (mean age, 54.6 ± 22.7 years) completed the study. Significant improvements in BCDVA, BCIVA, BCNVA, and contrast sensitivity were observed after 2 weeks of LVA-VR use (p < 0.001). Reading accuracy also improved significantly (p = 0.027); however, the reading speed did not change. Subject functionality improved, as indicated by the increase in the SFS (11.8 ± 4.5 vs. 19.6 ± 5.3) (p < 0.001). Most patients were satisfied with their visual function improvement and found LVA-VR to be useful in their daily activities. No device-related adverse events were observed or indicated. Conclusions: This study suggests that LVA-VR is beneficial for visual rehabilitation. Future technological advances are expected to improve LVA-VR performance and acceptability further for a better quality of life in low vision patients.

Real-time digital image processing to optimally enhance low vision is now realizable with recent advances in personal computers. This study aimed to evaluate the efficacy of a wearable smartphone-based low vision aid (LVA) with customizable vision enhancement in patients with visual impairment. We recruited 35 subjects with visual impairment and who were literate and cognitively capable. The subjects completed a training session and were provided a smartphone-based LVA for a 4-week use. Visual functions including binocular best-corrected distance, intermediate, and near visual acuities; reading performance (reading speed and accuracy); and facial recognition performance were measured at baseline and after 4-weeks use. All subjects also completed the Low Vision Quality of Life (LVQOL) Questionnaire. Thirty-four subjects (mean age, 43.82 ± 15.06 years) completed the study. Significant improvements in binocular best-corrected distance, intermediate, and near visual acuities were observed after smartphone-based LVA use (all p < 0.001). Reading accuracy and facial recognition performance also improved significantly (p = 0.009 and p < 0.001, respectively), but reading speed did not. LVQOL scores significantly improved after 4 weeks of use in subjects aged < 40 years (p = 0.024), but not in subjects aged ≥ 40 years (p = 0.653). Ocular and non-ocular adverse events were infrequent and resolved when the device was removed. The smartphone-based LVA with customizable vision enhancement could provide clinically significant improvements in the visual function of patients with visual impairment and was generally well tolerated. This study suggests that the smartphone-based LVA would be beneficial for visual rehabilitation.

Citation: Yeo JH, Jung BK, Lee H, et al. Development of a Pde6b gene knockout rat model for studies of degenerative retinal diseases. Invest Ophthalmol Vis Sci. 2019;60:1519-1526. https://doi.org/10.1167/ iovs.18-25556 PURPOSE. To describe the phenotypes of a newly developed Pde6b-deficient rat model of retinal degeneration.METHODS. Pde6b knockout rats were produced by CRISPR-Cpf1 technology. Pde6b knockout rats were evaluated for ocular abnormalities by comparison with wild-type eyes. Eyes were imaged using fundus photography and optical coherence tomography (OCT), stained by hematoxylin and eosin (H&E), and examined by TUNEL assay. Finally, eyes were functionally assessed by electroretinograms (ERGs). RESULTS.Pde6b knockout rats exhibited visible photoreceptor degeneration at 3 weeks of postnatal age. The fundus appearance of mutants was notable for pigmentary changes, vascular attenuation with an irregular vascular pattern, and outer retinal thinning, which resembled retinitis pigmentosa (RP) in humans. OCT showed profound retinal thinning in Pde6b knockout rats; the outer nuclear layer (ONL) was significantly thinner in Pde6b knockout rats, with relative preservation of the inner retina at 3 weeks of postnatal age. H&E staining confirmed extensive degeneration of the ONL, beginning at 3 weeks of postnatal age; no ONL remained in the retina by 16 weeks of postnatal age. Retinal sections of Pde6b knockout rats were highly positive for TUNEL, specifically in the ONL. In ERGs, Pde6b knockout rats showed no detectable a-or b-waves at 8 weeks of postnatal age.CONCLUSIONS. The Pde6b knockout rat exhibits photoreceptor degeneration. It may provide a better model for experimental therapy for RP because of its slower progression and larger anatomic architecture than the corresponding mouse model. Further studies in this rat model may yield insights into effective therapies for human RP.