Hereditary pigmented paravenous retinochoroidal atrophy.

A father and son with pigmented paravenous retinochoroidal atrophy demonstrated the classical fundus appearance of bilateral sharply circumscribed patches of retinochoroidal atrophy and pigmentation along the retinal veins. Our patients, and the preponderance of males in previously reported cases of this disease, suggest the possibility of Y-chromosome mediated male-to-male transmission. Electrophysiologic findings in our patients included elevated dark-adaptation thresholds, slightly reduced electroretinographic amplitudes, slightly prolonged a- and b-wave implicit times, and (in Case 1) abnormal electro-oculographic ratios. These findings indicate a diffuse tapetoretinal degeneration, and suggest that pigmented paravenous retinochoroidal atrophy is another incomplete form of retinitis pigmentosa.