Correlation between cortical somatosensory evoked potentials and MRI in patients with lumbosacral radiculopathy

ABSTRACT

MRI and somatosensory evoked potentials [SEP] have been used in evaluation of different aspects of radiculopathies. Investigators have been interested in comparative values of these tests. To determine the clinical value of truncular and dermatomal SEP in diagnosis, localization and prognosis of lumbosacral radiculopathy and its sensitivity relative to MRI. The lower extremity SEP studies were done in 34 patients with definite clinical and MRI findings of lumbosacral radiculopathy. The findings were compared with those obtained from the control group which consisted of 35 healthy individuals. Among 33 patients with abnormal MRI, 29 had abnormal SEPs [87.8%]. The concordance of SEP with MRI regarding the level and side of affected roots was 65.5%. MRI overestimates disc bulge in some patients. As a low-cost and sensitive tool, SEP is recommended to be used in addition to MRI in evaluation of lumbosacral radiculopathy