Visual electrophysiology and psychophysics in chronic alcoholics and in patients on tuberculostatic chemotherapy

Twenty-one chronic alcoholics and 15 patients on tuberculostatic therapy were examined on repeated occasions using flash electroretinography (ERG), flash and pattern visual evoked responses (VER), visual fields, and flicker fusion thresholds. For both groups of visually symptomless patients, there is evidence of retinal abnormalities although more abnormal results are seen for the VER's. The results indicate that the mode of action of alcohol and tobacco differs from that of the tuberculostatic drugs. For ethambutol and possibly isoniazid therapy, the larger changes which are seen in the flash VER's than in the pattern VER's, suggest that these drugs have a generalized effect upon the visual system. On the other hand, the results for the alcoholics indicate that the effect of alcohol and tobacco is more specific for the macular region as the macular thresholds and VER's to the small check and field size are most affected.