ABSTRACT
Purpose: The aim of this study was to elucidate the type of low vision devices (LVDs) prescribed for patients with cone dystrophy, cone–rod dystrophy, and rod–cone dystrophy and to analyze the visual improvement with the devices. Methods: A retrospective review of 300 electronic medical records of patients with cone dystrophy, cone–rod dystrophy, and rod–cone dystrophy referred to the low vision care (LVC) clinic for the first time between 2014 and 2016 at a tertiary eye care center was done. Collected data included the demographic profile of patients, details of LVDs, and best?corrected vision. Results: Out of 300 patients, 62.6% (n = 188) were male and 37.3% (n = 112) were female. Of the cases, 50% (n = 150) had cone–rod dystrophy, 45% (n = 135) had cone dystrophy, and 5% (n = 15) had rod–cone dystrophy. The most commonly prescribed LVD was SEE?TV binocular telescope (n = 6, 2.0%) for distance and dome magnifier (n = 60, 20%) for near. ET?40 dark grey tint (20.6%) was preferred for managing photophobia. There was a statistically significant difference in both distance and near visual acuities with LVDs (P < 0.05) in all categories, except rod–cone dystrophy. Conclusion: Early diagnosis with appropriate prescription of LVDs including tints helps in achieving good quality of vision in patients with cone?related dystrophies.
ABSTRACT
Retinitis pigmentosa (RP) is an inherited retinal dystrophy leading to progressive loss of vision and blindness. According to some studies the prevalence of RP is reported to be 1/3,000 to 1/5,000. The case presented with sudden painless diminution of vision with watering, slow adjustment from dark to light environments since 2 months. He was an apparently diagnosed case of RP. The treatment was scheduled for 24 weeks of 4 sittings and follow up period of 12 weeks. Outcome was measured based on changes in visual acuity and symptomatic relief. There was improvement in vision from 6/60p and 6/36p to 6/18 vision & 6/18p in right eye and left eye respectively. The progressive nature and lack of a definitive cure needs a cost effective, safe treatment protocol to preserve the existing vision, avoid further progression and restore vision.
ABSTRACT
PURPOSE: To investigate the morphologic changes in the outer retina of patients with cone dystrophy, using spectral-domain optical coherence tomography (SD-OCT). METHODS: The medical records of 15 cone dystrophy patients examined from January 2007 to January 2012 were reviewed retrospectively. All patients underwent ophthalmic evaluation including best-corrected visual acuity (BCVA), color vision testing, fundus examination, full-field standard electroretinography (ERG), multifocal (mf) ERG, and SD-OCT. Qualitative and quantitative SD-OCT data and ERG responses were analyzed and compared among the patient categories and the normal control group. RESULTS: There were 4 major categories of SD-OCT findings, based on the status of the ellipsoid portion of the photoreceptor inner segment (ISe), outer segment (OS) contact cylinder, and retinal pigment epithelium (RPE) layer. Category 0 showed no structural abnormalities. Category 1 showed foveal ISe loss and obscurity of the border between the ISe band and the external limiting membrane (ELM). Category 2 showed foveal thinning and focal foveal ISe disruption with an intact ELM. Category 3 showed foveal thickening and perifoveal disruption of the ISe layer. Category 1 to 3 showed OS contact cylinder layer absence and RPE thickening. The patients in category 0 tended to be younger (mean, 10.0 years) than those in categories 1 to 3 (mean, 17.6 years), although this difference was not statistically significant. Category 1 to 3 patients exhibited statistically significant thinning of the central retina and outer nuclear layer and thickening of the RPE layer relative to the category 0 and normal control group. There was a significant correlation between the central foveal thickness and BCVA in the patients with cone dystrophy. ERG and mfERG responses did not differ significantly among the different cone dystrophy categories. CONCLUSIONS: The morphologic features of cone dystrophy as revealed by SD-OCT, could be categorized as either normal or 1 of 3 different types of outer retinal changes. The presence of normal retinal structures in young cone dystrophy patients with functional impairment (category 0) indicates that electrophysiologic studies are superior to current imaging modalities for the early diagnosis of cone dystrophy. The characteristic SD-OCT findings in cone dystrophy patients may aid in differential diagnosis and be useful for future research on the pathology of cone dystrophy.