[Does circumscribed ischemic white matter lesion produce neuropsychological symptoms?]

In order to determine a possible role of ischemic white matter lesion in producing neuropsychological symptoms, we conducted a retrospective survey. Subjects were 206 consecutive patients who had been admitted to our neurology service under the diagnosis of ischemic stroke from April 1988 to November 1989 and had received brain CT as well as SPECT scans. From this cohort only patients that had circumscribed white matter lesion on CT scans were selected. Patients who had lesion in basal ganglia or thalamus were rigidly excluded. Eight subjects (3.9%) fulfilled above criteria, i.e. 5 with left hemispheric, 2 with right hemispheric and 1 with bilateral white matter lesions. Then we supplemented MRI information which had happened to be available for all the eight subjects. Exclusion of grey matter lesion based on MRI reduced the number of cases with exclusive white matter lesion into 4, i.e. 3 with left hemispheric and 1 with right hemispheric lesion. Of these, only one case with a discrete lesion in the genu of the left internal capsule had manifested mild neuropsychological impairments in naming, comprehension and writing. I123 amphetamine SPECT study revealed low uptake in the anterior half of the left middle cerebral artery in this case. We conclude that the role of a circumscribed white matter lesion as a cause of neuropsychological symptom seems to be much less clear than has been postulated.