Stargardt’s disease Fundus flavimaculatus

DESCRIPTION usually reveal a normal ERG in the early Stargardt’s disease is an autosomal reces- stages of the disease, becoming more sively inherited dystrophy of the macula. affected as the disease progresses. The Rarely, autosomal dominant forms have EOG is also usually normal. been described. In the recessive form of Stargardt’s disease, the ABCR gene, felt Advice by some to be mapped to the short arm of Unfortunately, early in the disease chromosome 1, has been identified as the process, labels such as malingering or causative agent. The autosomal dominant psychogenic amblyopia are sometimes form of the condition has been mapped used. People who malinger are often to chromosome 6. The term fundus flavi- aggressive and are trying to avoid some maculatus refers to the yellow fleck-like activity, such as going to school or military deposits which are typically seen in this service. Psychogenic amblyopes, unlike condition, and at one time, Stargardt’s malingerers, are usually mild mannered disease and fundus flavimaculatus were and actually experience their symptoms. thought to be separate entities. Signs may include a variable visual acuity, visual field and colour vision defects of SYMPTOMS Stargardt’s disease of the right fundus of a 35-year-old male, a non-organic nature, normal findings Typically, a child or young adult will showing early macular atrophy and flavimaculatus fleck when examining the anterior eye, pupil present with a progressive, bilateral, changes at the retinal pigment epithelial level responses and fundus, and convergence symmetrical loss of vision. The rate of and accommodation insufficiency. Such vision loss is usually fairly slow to about labels only serve to delay the correct 6/12, and thereafter can be more rapid diagnosis. to 6/60. Refractive correction or LVAs SIGNS There is no treatment for this condition. In the early stages of the disease, there Low vision and other rehabilitative may be little to see with the ophthal- services may be beneficial and genetic moscope, despite significant visual counselling should be considered. symptoms. Eventually, the macula assumes an atrophic beaten-metal appearance due to atrophy of the RPE with surrounding soft yellow flecks that are often characteristically fish-tailed or pisciform. These deposits at the level of the retinal pigment epithelium (RPE), which appear to be lipofuscin material, may involve a wide area of the central Stargardt’s disease of the right fundus of an 18-year-old male retina. In some cases, macular atrophy low vision patient. Advanced macular atrophy and yellow predominates and may have a bull’s-eye flavimaculatus flecks affected both fundi appearance, whereas in others the yellow flecks are the most obvious feature. The full series of these articles is available in the book Posterior Eye Disease and Glaucoma A-Z by Bruce AS, PREVALENCE O’Day J, McKay D and Swann P. £39.99. For further Stargardt’s disease has a prevalence of SEE ALSO information click on the Bookstore at opticianonline.net about 1 in 20,000. It is the pre-eminent Non-physiological visual loss. cause of degeneration of the macula ● Adrian Bruce is a Chief Optometrist at the Victorian affecting the RPE in the first two decades MANAGEMENT College of Optometry and a Senior Fellow, Department of life, comprising about 7 per cent of of Optometry and Vision Sciences, The University of all retinal dystrophies. Additional investigations Melbourne. Testing with an Amsler grid usually ● Justin O’Day is an Associate Professor in the DIFFERENTIAL DIAGNOSIS reveals central abnormalities and Department of Ophthalmology, The University of Other conditions that may produce typically macular photostress recovery Melbourne and Head Of Neuro-Ophthalmology Clinic, deposits or atrophy in the macular times are prolonged. Visual field testing Royal Victorian Eye and Ear Hospital. region include: Drusen, toxic maculopa- may reveal a loss of central sensitivity ● Daniel McKay is a Medical Officer at the Royal thies – from, for example, chloroquine, with normal peripheral fields. Macular Victorian Eye & Ear Hospital. tamoxifen and talc, Cone dystrophy, hyperfluoresence and a silent choroid ● Peter Swann is Associate Professor in the School of Fundus albipunctatus and Retinitis may be seen with fluorescein angiog- Optometry, Queensland University of Technology. punctata albecens. raphy. Electrophysiological testing will opticianonline.net 01.08.08 | Optician | 47