title: Age-related reduction in visually evoked cerebral blood flow responses.
abstract: The influence of aging on photoreactive flow changes in the posterior cerebral artery (PCA) was investigated in 38 healthy volunteers aged 20-81 years. Mean blood flow velocity (MBFV) was measured at rest and during 10-Hz photic stimulation by transcranial Doppler sonography. The amplitude of the evoked flow response significantly decreased with age (r = -0.39; P < 0.001). In a group of elderly subjects (60-81 years), the evoked blood flow velocity increase was 10.8 +/- 2.7%, which is less than in young subjects aged 20-39 years (14.7 +/- 4.3%; P = 0.001). We conclude that normal aging affects photoreactive flow changes in the occipital lobe. This may limit the application of functional imaging studies based on measurements of blood flow changes in the elderly.
authors.affiliation: Department of Neurology, Charité, Humboldt-University, Campus Virchow Klinikum, Augustenburger Platz 1, D-13353 Berlin, Germany. ludwig,niehaus@charite.de
authors.forename: L
authors.initials: L
authors.lastname: Niehaus
authors.forename: R
authors.initials: R
authors.lastname: Lehmann
authors.forename: S
authors.initials: S
authors.lastname: Röricht
authors.forename: B U
authors.initials: BU
authors.lastname: Meyer
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001783:Blood Flow Velocity / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009778:Occipital Lobe / Q000502:physiology; D010775:Photic Stimulation; D020769:Posterior Cerebral Artery / Q000502:physiology*; D018709:Statistics, Nonparametric