title: Perfusion computed tomography in the acute phase of mild head injury: regional dysfunction and prognostic value.
abstract: OBJECTIVE
  Traumatic brain injury is a major cause of disability and death. Most patients sustain a mild head injury with a subgroup that experiences disabling symptoms interfering with return to work. Brain imaging in the acute phase is not predictive of outcome, as 20% of noncontrast computed tomographic (CT) scans on admission is normal in patients with a suboptimal outcome. The aim of this study was to perform perfusion CT imaging in the acute phase of mild head injury in patients without intracranial abnormalities on the noncontrast CT, to assess whether these patients had cerebral perfusion abnormalities. Furthermore, the relation between perfusion CT parameters and severity of head injury and outcome was evaluated.
  
  
  METHODS
  In patients with mild head injury and normal noncontrast CT, perfusion CT was performed directly after admission. The perfusion data were compared with data of 25 healthy control subjects. Outcome was determined 6 months after injury with the extended Glasgow Coma Outcome Scale score and return to work.
  
  
  RESULTS
  Seventy-six patients were included. In patients with a decreased Glasgow Coma Scale score, a significant decrease of cerebral blood flow and cerebral blood volume was detected in the frontal and occipital gray matter. In logistic regression analyses, decreased cerebral blood flow and cerebral blood volume in the frontal lobes predicted worse outcome according to the extended Glasgow Coma Outcome Scale score. CT perfusion parameters did not predict return to work.
  
  
  CONCLUSIONS
  In the acute phase of mild head injury, disturbed cerebral perfusion is seen in patients with normal noncontrast CT correlating with severity of injury and outcome.
authors.affiliation: Department of Neurology, University Medical Center Groningen, Groningen, the Netherlands.
authors.forename: Zwany
authors.initials: Z
authors.lastname: Metting
authors.forename: Lars A
authors.initials: LA
authors.lastname: Rödiger
authors.forename: Roy E
authors.initials: RE
authors.lastname: Stewart
authors.forename: Matthijs
authors.initials: M
authors.lastname: Oudkerk
authors.forename: Jacques
authors.initials: J
authors.lastname: De Keyser
authors.forename: Joukje
authors.initials: J
authors.lastname: van der Naalt
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002560:Cerebrovascular Circulation / Q000502:physiology*; D006259:Craniocerebral Trauma / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D004651:Employment / Q000706:statistics & numerical data; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D011379:Prognosis; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult