Hypotrichosis with Juvenile Macular Dystrophy: Clinical and Electrophysiological Assessment of Visual Function

Purpose To evaluate retinal function in subjects suffering from hypotrichosis with juvenile macular dystrophy (HJMD). Design Retrospective case–control study. Participants Sixteen HJMD patients belonging to 2 genetic groups and 20 control subjects. Methods The HJMD patients underwent clinical ophthalmological examination and electrophysiological testing for a period of as many as 14 years. The electroretinogram (ERG), electro-oculogram (EOG), and visual evoked potential (VEP) were recorded serially to assess visual function and to follow possible progression of the disease. Main Outcome Measures Amplitudes and implicit times of ERG and VEP, and Arden ratio of EOG. Results Fundus examination revealed pigmentary abnormalities with atrophic changes at the posterior pole extending to regions beyond the macular area. A slow and time-dependent decline in visual acuity was noted. The ERG responses were subnormal in amplitude. The ERG deficit was similar for light- and dark-adapted responses. There was a gradual but consistent decrease in the ERGs with time. The EOG measurements were within the normal range. Pattern reversal VEPs were very subnormal, even in patients with mild deterioration of visual acuity. The flash VEPs were of slightly subnormal amplitudes and implicit times in the upper limit of the normal range. Conclusions The fundus pictures and electrophysiological tests were consistent with retinal involvement extending beyond the macular region. Follow-up of visual acuity and ERG testing indicated a slowly progressing retinal disorder affecting cone-mediated vision as well as rod-mediated vision. Therefore, we suggest that a more appropriate name for this syndrome is hypotrichosis with cone–rod dystrophy.