Evoked potentials and disability in multiple sclerosis: A different perspective to a neglected method

Evoked potentials and disability in multiple sclerosis: a different perspective to a neglected method.

Because evoked potentials (EP) are reflections of the functional integrity of sensory-motor systems, they are expected to reflect the abnormality in patients with disabilities and handicaps and also be in correlation with scales. This assumption was tested.

Patients with multiple sclerosis (MS) and myelopathy (M) and normal controls were investigated by EP, Multiple Sclerosis Walking Scale-12, timed 25-foot walk test and extended disability status scale (EDSS). EP results were converted to ordinal values, and correlations of these values with scales were calculated. Sensitivity and specificity analysis of EP parameters was also performed.

Total EP scores revealed high rates of abnormality in both groups, but MS revealed a different correlation pattern from M. The SEP+MEP summed score showed high sensitivity and specificity for MS and this was also correlated with the MS-related disability-ambulation scales including EDSS. The most specific parameter was the minimum M latency in the MEP study.

Four extremity recordings of EP with the use of more parameters than usual and ordinal expression of results seem to be benefical in MS. Although this study was cross sectional in nature, results indicated that EP might be useful in clinical follow up.