BackgroundAlbinism poses a significant threat to visual functions and causes remarkable ocular morbidity often resulting in visual disabilities. The study aimed at describing the visual status in patients with diagnosed cases of complete oculocutaneous albinism (OCA) attending to a tertiary eye hospital in Nepal.MethodsThis was a cross-sectional descriptive hospital-based study of all diagnosed oculocutaneous albinotic cases (16 males and 9 females; mean age of 16 years) who visited the Department of Ophthalmology at the Institute of Medicine, for ocular consultation between September 1, 2011 and December 1, 2013.ResultsTwenty-five cases (50 eyes) with OCA were enrolled in the study. All the participants had maximally reduced visual acuity (mean: 1.24 ± 0.50 logMAR). Myopic astigmatism was the most common refractive error (n = 17; 34%). 58% of all participants had with-the-rule astigmatism.Considering the spherical equivalent power, most of the eyes (n = 30; 60%) had myopia, with overall mean SE refractive error of −1.59 ± 5.39 D. Visual acuity improved significantly with refractive correction in place (paired sample t-test, p < 0.05). Horizontal pendular nystagmus was the most common nystagmus (n = 34 eyes; 68%). Alternating esotropia and alternating exotropia each were observed in 16% of participants who had strabismus (40% of all cases). The diaphanous iris, foveal hypoplasia and poliosis were the most consistent clinical features.ConclusionPatients with OCA present with a broad spectrum of visual deficits that impair the visual functions. Significant improvement in visual acuity following optical correction serves as an impetus to the reduction of visual disabilities in individuals with albinism.

Background Childhood blindness and low vision have become major public health problems in developing countries. The purpose of this study was to categorise the causes of visual impairment according to aetiology and provide detailed local information on visually impaired children seeking low‐vision services in a tertiary eye centre in Nepal. Methods A retrospective study was conducted of all visually impaired children (visual acuity of less than 6/18 in the better eye), aged less than 17 years seen in the low‐vision clinic at the Sagarmatha Chaudhary Eye Hospital in Lahan between January 1, 2012 and December 31, 2013. Results Of the 558 visually impaired children, the majority were males, 356 (63.7 per cent). More than half (56.5 per cent) of the children were in the 11 to 16 years age group. Many of the low‐vision children (52.9 per cent) were identified as having moderate visual impairment (visual acuity less than 6/18 to 6/60). Most children were diagnosed with childhood (36.2 per cent) or genetic (35.5 per cent) aetiology, followed by prenatal (22.2 per cent) and perinatal (6.1 per cent) aetiologies. Refractive error and amblyopia (20.1 per cent), retinitis pigmentosa (14.9 per cent) and macular dystrophy (13.4 per cent) were the most common causes of paediatric visual impairment. Nystagmus (50.0 per cent) was the most common cause of low vision in the one to five years age group, whereas refractive error and amblyopia were the major causes in the six to 10 and 11 to 16 years age group (17.6 and 22.9 per cent, respectively). Many of the children (86.0 per cent) were prescribed low‐vision aids and 72.0 per cent of the low‐vision aid users showed an improvement in visual acuity either at distance or near. Conclusion Paediatric low vision has a negative impact on the quality of life in children. Data from this study indicate that knowledge about the local characteristics and aetiological categorisation of the causes of low vision are essential in tackling paediatric visual impairment. The findings also signify the importance of early intervention to ensure a better quality of life.

PURPOSE. To investigate the action of atropine on global flash multifocal electroretinogram (gmfERG) responses to retinal defocus. METHOD. gmfERG recordings were made monocularly in 19 healthy adults under three lensimposed defocus conditions (2 diopters myopic, 2 diopters hyperopic, and no defocus) before and 24 hours after instillation of 1 drop of 0.1% atropine. Signals reflecting activity from the outer and inner retina (direct [DC] and induced [IC] components respectively) were analyzed. Responses were grouped into either a central (08-68) or peripheral (68-248) retinal zone. The gmfERG responses were compared relative to the no defocus, no atropine condition. RESULTS. Within the central zone, atropine had no effect on the amplitudes and peak times of DC or IC responses to defocus. For IC responses in the peripheral zone, there was a significant interaction effect of atropine and defocus (F 2,36 ¼ 6.050, P ¼ 0.011) with greater post-atropine amplitudes under myopic defocus (mean increase ¼ 15.5%, 95% confidence interval [CI] ¼ 5.6%-25.4%, P ¼ 0.004). Atropine also had a significant main effect of increasing IC peak times (F 1,18 ¼ 9.722, P ¼ 0.006). For DC responses, atropine had a significant main effect of increasing DC amplitudes (F 1,18 ¼ 7.821, P ¼ 0.012) and peak times (F 1,18 ¼ 15.406, P ¼ 0.001) regardless of sign of defocus. CONCLUSIONS. Our results imply that atropine acts in the inner layers of the peripheral retina to affect neuronal responses to myopic defocus, raising the possibility that atropine may potentiate the effects of myopic defocus in inhibiting eye growth.

The role of accommodation in myopia development and progression has been debated for decades. More recently, the understanding of the mechanisms involved in accommodation and the consequent alterations in ocular parameters has expanded. This International Myopia Institute white paper reviews the variations in ocular parameters that occur with accommodation and the mechanisms involved in accommodation and myopia development and progression. Convergence is synergistically linked with accommodation and the impact of this on myopia has also been critiqued. Specific topics reviewed included accommodation and myopia, role of spatial frequency, and contrast of the task of objects in the near environment, color cues to accommodation, lag of accommodation, accommodative-convergence ratio, and near phoria status. Aspects of retinal blur from the lag of accommodation, the impact of spatial frequency at near and a short working distance may all be implicated in myopia development and progression. The response of the ciliary body and its links with changes in the choroid remain to be explored. Further research is critical to understanding the factors underlying accommodative and binocular mechanisms for myopia development and its progression and to guide recommendations for targeted interventions to slow myopia progression.

Background: Quantifying blood perfusion in ocular tissues is challenging, partly because the majority of the blood is carried by the choroid, which is difficult to visualize because it is located between the retina and sclera. Purpose/Hypothesis: To evaluate the intra-and interday repeatability of MRI measures of chorio-retinal blood perfusion. Study Type: Prospective, cross-sectional, observational study. Population: Twenty young healthy adults (six male, age: 25 ± 5 years) scanned twice within a single session repeated at the same time of day on 2 days. Field Strength/Sequence: Arterial spin labeling (ASL) MRI at 3.0T using pseudocontinuous ASL (PCASL) labeling scheme and a 3D turbo-gradient-spin-echo (TGSE) acquisition, including axial T 2 -weighted structural images using a 2D turbo-spinecho (TSE) sequence. Assessments: Region-of-interest analysis for assessment of chorio-retinal blood perfusion. Statistical Tests: Intra-and interday repeatability of measures analyzed using intraclass correlation coefficients (ICC), Pearson's correlation analysis, paired t-tests, and Bland-Altman plots. Results: The mean chorio-retinal perfusion was 77.86 (standard deviation [SD] = 29.80) ml/100ml/min. Perfusion measurements correlated strongly within a single session (r = 0.95, 95% confidence interval [CI] [0.880-0.980], P < 0.001) and between the two sessions based on a single run (r = 0.80 [0.582-0.913], P < 0.001), and two runs (r = 0.80 [0.479-0.918], P < 0.001). There were mean differences of 2.69 [16.85 to -22.23] ml/100ml/min for intraday measures, -7.44 [27.45 to -42.32] ml/100ml/min for single-run interday measures, and 5.73 [28.71 to -40.17] ml/100ml/min for two-run interday measures, but none were significant (all P > 0.05). Data Conclusion: Quantitative ASL-MRI measurements of chorio-retinal blood perfusion showed high intra-and interday repeatability. The ASL-MRI technique provides reliable measures of chorio-retinal perfusion in vivo. Level of Evidence: 1 Technical Efficacy Stage: 2 J. MAGN. RESON. IMAGING 2019;49:966-974.T he inner retina is perfused with blood from the retinal circulation via the central retinal artery, but the outer retina receives its supply from the choroid, a separate vascular bed which carries the vast majority of the total ocular blood supply. 1 Impaired or inadequate blood flow in either the retinal or choroidal circulation leads to ischemic retinal diseases, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR). 2,3 However, the exact pathogenesis of ischemic retinal diseases are not fully understood, in part due to the difficulty in obtaining absolute measures of retinal and choroidal blood perfusion.Several techniques have been used previously to measure blood flow in the retina/choroid complex, including fluorescein and indocyanine-green angiography, laser Doppler flowmetry (LDF), laser speckle imaging, color Doppler imaging, pulsatile ocular blood flowmetry, and ophthalmo-dynamometry. 4 Although these blood flow assessment techniques yield insight into ocula...

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The RNFL thickness measurements with SD-OCT are lower in glaucomatous eyes as compared to age-matched GS and normal eyes in the Nepalese population. A high resolution SD-OCT could aid significantly in the early diagnosis of glaucoma in Nepal.

Every sport requires a set of visual skills that are critical elements to most sports performance. A considerable debate has taken place concerning the role of vision in sports performance but it is the training of these specific skills that influence to strengthen specific visual abilities resulting in actually improved performance. This article highlights the current perspectives on the importance of visual training on visual skills enhancement leading to an improved performance in sports. It also gives further insights in the need of future longitudinal trials involving athletes from diverse sports as well as recommends visual skills training to be included in the routine training of the athletes at all levels.