Diagnostic value of visual evoked potentials for clinical diagnosis of multiple sclerosis.

Abstract

Prolonged latency of visual evoked potentials (VEP) has been used to identify clinically silent lesions in multiple sclerosis (MS) suspects. The objective of this study was to determine the reliability of VEP to predict the development of MS in MS suspects. Retrospective hospital records of MS suspects were evaluated. VEP was analyzed together with subsequent diagnostic confirmation of MS by McDonald diagnostic criteria for MS-2005. MS developed in 12 of 35 patients (34 %) and 23 (66 %) failed to exhibit diagnostic characteristics. P100 latencies and interocular latency differences were longer in clinically definite multiple sclerosis (CDMS) than non-CDMS patients (p = 0.002, 0.001, respectively). All patients in the subsequent MS group had P100 latencies longer than102 ms, a mean of our MS-free subjects thus providing 100 % of sensitivity. No patient developed MS with a P100 latency <102 ms. Brain MRI lesions associated significantly with developing CDMS (p = 0.001). Predictability of developing CDMS was highest when criteria for P100 latency, interocular latency difference, and brain MRI lesions were combined. MS suspects with a P100 latency longer than mean of MS-free subjects are more likely to develop MS than those with lower values. VEP latency combined with MRI could improve the accuracy of MS prediction.