Visual evoked potential changes in migraine - Influence of migraine attackand aura

Objective: To assess the visual evoked potential (VEP) changes in migraines with and without aura. Study design: A clinical study in which the VEP res ults of 45 migraineurs (study group) and 22 healthy volunteers (control gro up) were compared. Of 45 migraineurs, 29 had migraine with aura (MA) and 16 had migraine without aura (MOA), and they were examined both during and be tween the migraine attacks. Methods: The patients and healthy controls unde rwent VEP assessment. On VEP recording, mono-ocular stimulation was perform ed by means of the pattern reversal check board. The latencies of N1, P1 an d N2, and the N1-P1 amplitude were noted. The following comparisons were ma de between NI, P1 and N2 latencies and N1-P1 amplitudes of the migraine and control groups; during and between attack the VEP results of the patients with MA and MOA. Results: The VEP results of the migraineurs and healthy co ntrols were similar (P>0.05). The during attack results of MA, during and b etween attack results of MOA, and the results of the control group were als o similar (P>0.05). N2 latency significantly elongated in patients with MA in the attack free period than it was during the attack (P=0.01), and was a lso longer than it was in the control group (P=0.01). Conclusions: There is involvement of the visual pathway in MA rather than MOA, and differentiati on between these subtypes of the migraine disease may be performed on the b asis of VEP findings manifesting by the prolongation of the N2 wave latency . This contention should be confirmed by further studies. (C) 2001 Elsevier Science BN. All rights reserved.