Myelinated retinal nerve fibers: prevalence, location and effect on visual acuity.

We examined fundus photographs of 5,789 patients (11,578 eyes) and found 39 patches of myelinated nerve fibers in 35 eyes of 33 patients. The prevalence was 0.57%. The lesion was more frequent in females than in males. The patch occurred more often at the superior sectors of the nerve head and in the inferotemporal retina than in other areas. No myelinated nerve fibers were discovered in the macula. One patient (case 1) had 3 patches in 1 eye. Two patients (cases 2 and 3) had unilateral myelinated nerve fibers, bilateral myopia and ipsilateral amblyopia. In case 3, the patch was associated with an epiretinal membrane. Another patient (case 4) had branch vein occlusion and neovascularization from the patch of myelinated nerve fibers. The fundus conditions observed in our cases 1-4 may be uncommon.