[Visual evoked potentials in the differential diagnosis of vascular and demyelinating disorders of the optic nerve].

In 21 patients with idiopathic retrobulbar neuritis (IRN) the optic nerve function was assessed using visual evoked potentials under a reversible black-and-white chessboard pattern stimulation. Latencies of the large positive wave P100 significantly increased in all IRN patients ipsilaterally to the diseased eye and in a half of the patients contralaterally. Amplitude reduction in the evoked response to the diseased eye stimulation with unaffected eye P100 parameters within the normal range was most characteristic of IRN. These criteria can be used for differential diagnosis of vasculogenic and demyelinating lesions of the optic nerve.