Abstract
Purpose: :
Pattern macular dystrophy is a group of rare inherited retinal diseases in which there is abnormal accumulation of lipofuscin-like material at the level of retinal pigment epithelium (RPE). There is a wide spectrum of macular findings described in literature ranging from flecks to a more typical butterfly-shaped lesion. There are isolated reports in literature describing histopathological findings in such patients. The advent of spectral-domain optical coherence tomography (SD-OCT) has enhanced our understanding of retinal diseases. The present study describes the OCT and fundus autofluorescence (FAF) features in patients with pattern dystrophy to possibly provide more insight into the pathophysiology of this disease.
Methods: :
Ten eyes of five patients clinically diagnosed with pattern macular dystrophy were included in the study. Their ages ranged from 43 to 81 years and there were three men and two women in the cohort. All patients underwent a complete ophthalmological examination including Snellen visual acuity and color vision testing. Color fundus photography, SD-OCT, FAF and infra-red (IR) imaging were performed on all patients. Fluorescein angiography, microperimetry (MP-1) and electrophysiological testing were performed, wherever appropriate.
Results: :
The Snellen visual acuity in the five patients with pattern dystrophy ranged from 20/20 to 20/70. The clinical features ranged from yellowish flecks in the macular area to pigmented lesions in all patients with some showing patches of atrophy. SD-OCT showed localized areas of RPE changes corresponding to the yellowish lesions with an intact photoreceptor layer. There were areas of hyperautofluorescence on FAF corresponding to areas of lipofuscin-like deposits and hypoautofluorescence in areas of RPE atrophy. Retinal function, as measured by visual acuity and MP-1 correlated well with the presence of normal photoreceptor layer.
Discussion: :
The characteristic changes in patients with pattern dystrophy, as defined by the evolving technology of SD-OCT and FAF and the retinal functional correlation help us to better understand the pathophysiological mechanisms involved in the disease. Future studies evaluating long-term follow-up of these patients will help to better define the course of the disease.
Keywords: macula/fovea • photoreceptors • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)