[Paraclinical tests in multiple sclerosis. Clinical correlation and predictive value]

The correlation between clinical signs and symptoms, Evoked Potentials (EP) and Magnetic Resonance Imaging (MRI) in Multiple Sclerosis (MS) is still uncertain. It seems necessary to perform comparative studies with homogeneous groups of patients to avoid the error provoked by the selection of patients and the use in the diagnosis of EP and MRI. The aims of this paper were to calculate the sensitivity of EP and MRI in MS in relation to time of evolution and type of MS, to determine the correlation between clinical data and EP and MRI alterations, and to show the predictive value of the paraclinical tests. We have performed clinical examination, EP and MRI in 47 patients with clinically definite MS, Poser's category 1a, without acute attack. Our results show significant correlation between VEP and visual functional scale (FS) (r = 0.43), brainstem auditory EP (BAEP) and Expanded Disability Status Scale (EDSS) (r = 0.33), BAEP and cerebellar FS (r = 0.36), BAEP and brainstem FS (r = 0.29) and somatosensory EP (SEP) and pyramidal FS (r = 0.4). Also, we found significant correlation among clinical data and MRI abnormalities in cerebellum (p < 0.01), brainstem (p < 0.001), and spinal cord (p < 0.01). The SEP (74%), cerebellar (92%) and spinal (83%) MRI alterations provided the greatest agreement with presumed clinical abnormalities. These data confirm the efficacy of EP and MRI to describe the status of MS and support its utility to evaluate the evolution.