title: Serial single-photon emission computed tomographic and transcranial doppler measurements for evaluation of vasospasm after aneurysmal subarachnoid hemorrhage.
abstract: OBJECTIVE
  To assess the clinical value of serial single photon-emission computed tomographic (SPECT) measurements after aneurysmal subarachnoid hemorrhage (SAH).
  
  
  METHODS
  Thirty-two patients were studied prospectively during the first 26 days after SAH with repeated SPECT measurements, clinical examinations, and transcranial Doppler recordings. Time trends were analyzed with a general linear model. A final SPECT measurement was performed after 1 year.
  
  
  RESULTS
  A mean of 2.6 (range, 1-5) SPECT measurements revealed a significant (P = 0.001) quadratic curve consistent with initial hypoperfusion and then with hyperperfusion during the acute stage. SPECT findings were significantly associated with transcranial Doppler recordings (P = 0.016) and clinical assessments (P = 0.008). Patients fulfilling clinical and transcranial Doppler criteria for vasospasm demonstrated a more pronounced relative hypoperfusion-hyperperfusion time course. A multivariate logistic regression analysis identified SPECT measurements obtained during Days 7 to 14 after the SAH as the only independent predictor (beta = 0.042, P = 0.02) for impaired perfusion after 1 year.
  
  
  CONCLUSIONS
  Serial SPECT measurements after aneurysmal SAH demonstrate that regional changes in cerebral perfusion follow a nonlinear time trend, and repeated measurements are necessary. This observation, as well as the low feasibility of SPECT, restricts the clinical value of such measurements.
authors.affiliation: Department of Neurosurgery, University Hospital of North Norway, Tromsø, Norway.
authors.forename: Arild
authors.initials: A
authors.lastname: Egge
authors.forename: Hans
authors.initials: H
authors.lastname: Sjøholm
authors.forename: Knut
authors.initials: K
authors.lastname: Waterloo
authors.forename: Tore
authors.initials: T
authors.lastname: Solberg
authors.forename: Tor
authors.initials: T
authors.lastname: Ingebrigtsen
authors.forename: Bertil
authors.initials: B
authors.lastname: Romner
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001931:Brain Mapping; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D011446:Prospective Studies; D012044:Regression Analysis; D012720:Severity of Illness Index; D013345:Subarachnoid Hemorrhage / Q000150:complications*; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology