title: Changes in cerebral blood flow during cerebrospinal fluid pressure manipulation in patients with normal pressure hydrocephalus: a methodological study.
abstract: The combination of cerebral blood flow measurement using (15)O-water positron emission tomography with magnetic resonance coregistration and CSF infusion studies was used to study the global and regional changes in CBF with changes in CSF pressure in 15 patients with normal pressure hydrocephalus. With increases in CSF pressure, there was a variable increase in arterial blood pressure between individuals and global CBF was reduced, including in the cerebellum. Regionally, mean CBF decreased in the thalamus and basal ganglia, as well as in white matter regions. These reductions in CBF were significantly correlated with changes in the CSF pressure and with proximity to the ventricles. A three-dimensional finite-element analysis was used to analyze the effects on ventricular size and the distribution of stress during infusion. To study regional cerebral autoregulation in patients with possible normal pressure hydrocephalus, a sensitive CBF technique is required that provides absolute, not relative normalized, values for regional CBF and an adequate change in cerebral perfusion pressure must be provoked.
authors.affiliation: Academic Neurosurgery Unit, Addenbrooke's Hospital, University of Cambridge, Cambridge, United Kingdom. brianowl@bigpond.com
authors.forename: Brian K
authors.initials: BK
authors.lastname: Owler
authors.forename: Alonso
authors.initials: A
authors.lastname: Pena
authors.forename: Shahan
authors.initials: S
authors.lastname: Momjian
authors.forename: Zofia
authors.initials: Z
authors.lastname: Czosnyka
authors.forename: Marek
authors.initials: M
authors.lastname: Czosnyka
authors.forename: Neil G
authors.initials: NG
authors.lastname: Harris
authors.forename: Piotr
authors.initials: P
authors.lastname: Smielewski
authors.forename: Tim
authors.initials: T
authors.lastname: Fryer
authors.forename: Tim
authors.initials: T
authors.lastname: Donvan
authors.forename: Adrian
authors.initials: A
authors.lastname: Carpenter
authors.forename: John D
authors.initials: JD
authors.lastname: Pickard
mesh_terms: D000368:Aged; D015170:Cerebrospinal Fluid Pressure; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000134:cerebrospinal fluid* / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D013223:Statistics as Topic; D014055:Tomography, Emission-Computed / Q000295:instrumentation / Q000379:methods*