Cognition, Ventricular Size, and Leuko-Araiosis

\s=b\Multi-infarct dementia (MID) and dementia of the Alzheimer type (DAT) were compared with regard to ventricular size and leuko-araiosis (LA) on computed tomographic scans. Ninety-seven percent of patients with MID and 55.5% of patients with DAT had evidence of LA. The severity of LA was scored with a 0 through 4 rating system, and LA was found to be significantly more severe in patients with MID than in patients with DAT. Patients with MID, but not those with DAT, exhibited correlations between enlargement of the third and lateral ventricles and severity of cognitive impairment. (Arch Neurol 1988;45:719-721) Clinical differentiation of dementia of the Alzheimer type (DAT) from multi-infarct dementia (MID) may be difficult, particularly if a typical his¬ tory of transient ischemie attacks or cerebrovascular accidents is missing. Numerous attempts have been made to identify reliable computed tomographic (CT) characteristics that aid in the differential diagnosis of demen¬ tia or distinguish dementia syn¬ dromes from normal aging. Except for the presence of overt infarctions in vascular dementia, however, valid cri¬ teria for distinguishing DAT from MID by CT scan have not been identi¬ fied. Recently, attention has focused on leuko-araiosis (LA), defined as areas of increased lucency in the white mat¬ ter of the cerebral hemispheres.13 Leuko-araiosis has been described in demented and nondemented patients with cerebrovascular disease,4 in patients with DAT, and in normal elderly individuals.57 Unresolved questions remain concerning the dif¬ ferential diagnostic value of LA, the relationship of LA to dementia severi¬ ty, and the relationship of LA to changes in ventricular size. The cur¬ rent study was undertaken to explore the presence and severity of LA in patients with MID and in patients with DAT with similar degrees of intellectual impairment. The relation¬ ships of LA and linear ventricular measurements to intellectual impair¬ ment were also investigated.