Magnetic resonance imaging in isolated noncompressive spinal cord syndromes.

The frequency with which patients presenting with acute or chronic noncompressive cord syndromes subsequently develop multiple sclerosis is uncertain. Magnetic resonance imaging (MRI) was performed on 121 patients with such syndromes to determine the frequency of asymptomatic brain lesions and to assess the sensitivity of MRI in detecting the local cord lesion. MRI findings were compared with those from visual, brainstem, and somatosensory evoked potentials (VEPs, BAEPs, SEPs), and cerebrospinal fluid electrophoresis. Lesions were seen in the appropriate cord region in 47 of 73 patients (64%) with a cervical syndrome, and in 7 of 25 patients (28%) with a thoracic or lumbar syndrome. MRI demonstrated more cervical lesions than did SEPs, but fewer thoracic or lumbar lesions. Cord swelling was seen in 6 patients and atrophy in 10. Of those with acute syndromes, abnormalities were seen with brain MRI in 18 of 32 patients (56%), with VEPs in 2 of 30 patients (7%), and with BAEPs in 2 of 24 patients (8%). In patients with chronic syndromes, abnormalities were seen with brain MRI in 73 of 89 patients (82%), with VEPs in 22 of 80 patients (28%), and with BAEPs in 12 of 62 patients (19%). Brain MRI was thus more sensitive than evoked potentials were in establishing multiplicity of lesions. However, in acute syndromes, it was not possible to diagnose multiple sclerosis from a single abnormal brain scan in chronic syndromes, a diagnosis of clinically probable multiple sclerosis could be made from one scan, provided there was no better explanation for the abnormalities: the added presence of oligoclonal bands allows a diagnosis of laboratory-supported, definite multiple sclerosis as was the case in 28 patients in this series.