Table 2.

MRI and visual evoked potential findings

Feature		Number of patients	Percentage
Abnormal MRI	one lesion	4184	27.3%
	two lesions	16	10.7%
	three lesions	15	10%
	four lesions and more	12	8%
	Total	84	56%
Abnormal VEP	prolonged latency	135	90%
	non recordable	15	10%
	reduced amplitude	42	28%
	Total	150	100%