Cortical deficits in multiple sclerosis on the basis of subcortical lesions

Abstract

Patients suffering from multiple sclerosis have a high frequency of cognitive deficits usually attributable to demyelination and axonal loss in the subcortical white matter. Neurologic abnormalities referable to cortical function are uncommon but have been described. The present study describes three patients with clinically definite MS with deficits in cognitive function referable to cortical location. Two of the patients underwent positron emission tomography and showed profound cortical hypometabolism adjacent to subcortical white matter lesions seen on MRI. This paper points out that neurologic deficits referable to cortical sites may be caused by subcortical white matter lesions and that cognitive dysfunction in patients with MS may progress rapidly in the absence of motoria deficits or other evidence of clinical deterioration.