Optic pathway conduction in insulin-dependent diabetics.

Abnormal latency delay of pattern-reversal visual evoked cortical potentials (VECPs) has been demonstrated in insulin-dependent diabetics without retinopathy as a sign of subclinical damage. Pattern-reversal VECPs and onset-offset (on-off) VECPs probably originated at different cortical levels. On-off latencies of a group of 50 insulin-dependent diabetics without retinopathy or neuropathy and with normal oscillatory potentials have been studied in relation to various clinical and metabolic parameters. The results of our study showed that on-off VECPs have in diabetes the same latency alterations as pattern-reversal VECPs, if to a lesser extent. This finding can be a useful index in the evaluation of patients at risk.