Leuko-Araiosis and cerebral hypoperfusion compared between patients with ischemic vascular dementia and normal...

Lesions in white matter of unknown origin among the elderly have been of interest for many years, and their pathogenesis and clinical significance need clarification. Local cerebral blood flow was measured among patients with ichemic vascular dementia (IVD, n = 38) and compared with age-matched normal volunteers (n = 18) utilizing xenon-enhanced computed tomography (CT). Volume ratios for total leuko-araiosis, as well as volume ratios for apparently normal white and gray matter, were determined by plain, noncontrasted CT densitometry throughout slices of brain examined later during stable xenon inhalation enabling perfusion values for each compartment to be compared. Volume ratios for total leuko-araiosis to total brain parenchyma were twice as large among patients with IVD (12.0 ± 5.6%) compared with elderly normal volunteers (6.0 ± 2.7%). However, cerebral perfusion values within regions of leuko-araiosis compared to"normal" white matter were decreased to the same degree among patients with IVD (14 ± 6 ml/100 g brain/min) and among elderly normal volunteers with leuko-araiosis (13 ± 5). Local cerebral blood flow values were reduced for all regions of brain examined among IVD patients compared with age-matched normals. Among patients with IVD, multiple regression analyses correlated increased volumes of leuko-araiosis with (a) advancing age, (b) hypertension, and (c) reduced perfusion in vascular territories supplying the putamen. Hypoperfusion within deep cerebral territories correlates with pathogenesis of leuko-araiosis among patients with ischemic vascular dementia.