Decreased cerebrovascular dilatory capacity in subjects with asymptomatic periventricular hyperintensities

Abstract

Background and PurposeThe clinical significance of the periventricular hyperintensity incidentally found on magnetic resonance images of the brain is questionable. We evaluated resting cerebral blood flow and cerebrovascular dilatory capacity of subjects with asymptomatic periventricular hyperintensities to study their cerebral hemodynamics. MethodsMagnetic resonance imaging of the brain was performed in 28 asymptomatic subjects with cerebrovascular risk factors to determine the severity of periventricular hyper-intensity. Mean gray matter flow was computed by a133Xe-clearance technique in subjects at rest and after the administration of 1 g acetazolamide. Flow values were correlated with the scores for periventricular hyperintensity. ResultsResting gray matter flow was not significantly correlated with the severity of periventricular hyperintensity for the whole brain (rs= -.364), whereas flow after acetazolamide loading (rs= -.783, P