Visual Evoked Potentials in Migraine

The recording of visual evoked potentials (VEP) is used by neurophysiologists for the diagnosis of interruption of the optic pathways, mainly in the diagnosis of multiple sclerosis [12]. Pathologic changes in VEP do not necessarily reflect structural damage, but can be caused by neurotransmitter abnormalities, as in Parkinson’s disease [2,5]. The usefulness of visual evoked potential recordings in patients suffering from migraine is debatable with respect to both qualitative and quantitative pathology (Table 1). This could be attributed to the different stimulation techniques used and the often small number of patients tested. The pathologic results reported in the literature include delay and shortening of the latency of different peaks within the VEP, as well as increased amplitudes and asymmetries of the VEP across the occipital and parietal region. Normal VEP findings have also been reported. Given this controversy, we examined a large group of patients with migraine, and we also investigated whether it is possible to separate different forms of migraine (i.e., common migraine, ophthalmic migraine, migraine accompagnee) by means of visual evoked potential recordings.