Low Vision Management in a Case of Stargardt's Disease

Abstract

Background: By the WHO definition “a person with low vision is a one who has impairment of visual functioning even after treatment, surgery or standard refractive correction and has a visual acuity of less than 6/18 to light perception or a visual field of < 10⁰ from the point of fixation, in the better eye but who is potentially able to use vision for the planning and execution of a task.” Stargardt’s disease is one of the commonest inherited retinal disorders, with a prevalence of 1 in 10,000. It is inherited as an autosomal recessive trait [1,2]. Most cases present with central visual loss and there is typically macular atrophy and with yellow-white flecks at the posterior pole, which are at the level of the retinal pigment epithelium (RPE). Autofluorescence (AF) imaging and fluorescein angiography can be helpful in the confirming the diagnosis [3,4]. The age of onset is usually in the early teens, but there is wide variation, with a later age of onset being associated with a better visual prognosis [5,6]. Case: A 26 year old female presented to the low vision clinic of B.P. Koirala Lions Center for Ophthalmic Studies after final diagnosis of B/L Stargardt’s disease and her presenting visual acuity of 0.5 logMAR in RE and 0.56 logMAR in her LE. She had no previous history of any ocular pathology, trauma in the past. She had no history of any systemic illness known to her and no similar history of vision loss in other family members. Her visual acuity was decreasing since 8 years which was apparently well 8 years back. The anterior segment was within normal limits and on dilated fundus examination on mydriasis there was typical honeycomb appearance of the macular region. On cycloplegic retinoscopy there was final subjective prescription of -0.50 DC X 180 axis but no improvement in her visual acuity in her both eyes. Her near visual acuity was N12 at 33cm of working distance. With the spectacle clip on telescope (1.5X) her visual acuity improved to 0.20 logMAR. 54% yellow filter as spectacle was also prescribed and approach magnification was also taught. Finally the patient was managed with 1.5X spectacle clip on telescope for distance, bar magnifier (1.5X) for near and 54% yellow filter for management of photophobia. Conclusion: Stargardt’s disease can be managed properly with improvement in visual acuity for both near and distance with significant improvement in visual acuity for both near and distance with significant improvement in other visual functions with low vision devices.