Optical Coherence Tomography Finding in Occult Macular Dytrophy

Purpoe To determine the bai for unexplained viual acuity lo in elected patient. Deign Obervational tudy of patient with unexplained reduced viual acuity. Method We ued optical coherence tomography (OCT) to evaluate foveal tructure in eight patient. Thee patient had corrected viual acuitie of 20/25 to count finger in one or both eye and a normal ocular examination. We recorded foveal cone electroretinogram (ERG) a an objective meaure of foveal function. Reult even patient howed reduced foveal thickne aociated with thinning of the outer nuclear layer (ONL), and five of thee patient alo had reduced foveal cone ERG. One patient had normal tomogram and reduced foveal ERG. Concluion Unexplained reduction in viual acuity may reult from photoreceptor lo or foveal malfunction without photoreceptor lo, which are indicator of occult macular dytrophy. OCT and the foveal cone ERG together appear to be ufficient to identify the bai for viual acuity lo in thee patient.