[Cerebral edema and changes of cerebral blood volume in patients with head injuries].
OBJECTIVE
The pathogenesis of traumatic brain swelling remains unclear. The generally held view is that brain swelling is caused primarily by vascular engorgement and that edema plays a relatively minor role in the swelling process. The goal of this study was to examine the roles of cerebral blood volume (CBV) and edema in traumatic brain swelling.


METHODS
Both brain-tissue water and CBV were measured in 76 head-injured patients, and the relative contribution of edema and blood to total brain swelling was determined. Comparable measures of brain-tissue water were obtained in 30 healthy volunteers and CBV in seven volunteers. Brain edema was measured using magnetic resonance imaging, implementing a new technique for accurate measurement of total tissue water. Measurements of CBV in subgroup of 31 head-injured patients were based on consecutive measures of cerebral blood flow (CBF) obtained using stable xenon and calculation of mean transit time by dynamic computerized tomography scanning after a rapid bolus injection of iodinated contrast material.


RESULTS
The mean (+/- standard deviation) percentage of swelling due to water was 9.37 +/- 8.7%, whereas that due to blood was -0.8 +/- 1.32%.


CONCLUSIONS
The results of this study showed that brain edema is the major fluid component contributing to traumatic brain swelling. Moreover, CBV is reduced in proportion to CBF reduction following severe brain injury.
Barzó
Pál
P
Szegedi Tudományegyetem, Altalános Orvostudományi Kar, Szent-Györgyi Albert Orvos és Gyógyszerésztudományi Centrum, Idegsebészeti Klinika, Szeged. barzo@orto.szote.u-szeged.hu
Marmarou
Anthony
A
Fatouros
Panos
P
Portella
Gennarina
G
Czigner
Andrea
A
Bullock
Ross
R
Young
Harold
H
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D001810:Blood Volume; D001929:Brain Edema / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D002908:Chronic Disease; D006259:Craniocerebral Trauma / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D014057:Tomography, X-Ray Computed