Changes in cerebral blood flow during cerebrospinal fluid pressure manipulation in patients with normal pressure hydrocephalus: a methodological study.
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.
Owler
Brian K
BK
Academic Neurosurgery Unit, Addenbrooke's Hospital, University of Cambridge, Cambridge, United Kingdom. brianowl@bigpond.com
Pena
Alonso
A
Momjian
Shahan
S
Czosnyka
Zofia
Z
Czosnyka
Marek
M
Harris
Neil G
NG
Smielewski
Piotr
P
Fryer
Tim
T
Donvan
Tim
T
Carpenter
Adrian
A
Pickard
John D
JD
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*