Autosomal dominant vitreoretinochoroidopathy with normal electrooculogram in a German family

Background: Autosomal dominant vitreoretinochoroidopathy (ADVIRC) is a rare disorder previously described in four families residing in the USA and one family residing in Germany. We report the clinical and unexpected electrophysiological findings in a sixth family, residing in Germany. Methods: An affected 23-year-old man, his 52-year-old affected mother and his 55-year-old unaffected father were examined by testing visual acuity, fluorescein angiography, visual fields, dark adaptation, electrooculography (EGG) and electroretinography (ERG). Results: The 23-year-old man showed a circumferential retinochoroidal dystrophy extending from the mid-periphery to the ora serrata. There was a sharp demarcation between affected and nonaffected retina. Peripheral to the damarcation, bone spicules and yellow-white deposits were present, and the retinal vessels were severely attenuated. In addition, vitreous opacities were present. The EOG light rise was normal. The ERG amplitudes were reduced to 35% of the normal in all recording conditions. The 52-year-old mother showed marked peripheral pigmentation, but no bone spicules, deposits or vitreous opacities. Her EOG and ERG recordings were normal. Conclusions: Expression of ADVIRC can be very variable within the same family. A reduced EOG light rise, previously suggested as a characteristic sign for ADVIRC, is not a typical sign for all affected patients.