title: Whole brain CT perfusion combined with CT angiography in patients with subarachnoid hemorrhage and cerebral vasospasm.
abstract: OBJECTIVE
  To assess cerebral vasospasm (CVS) and monitor cerebral microcirculatory changes in patients with acute subarachnoid hemorrhage (SAH) via CT angiography (CTA) combined with whole-brain CT perfusion (CTP) techniques.
  
  
  METHODS
  Sixty patients with SAH (SAH group) and 10 patients without SAH (control group) were selected for a prospective study. CTP combined with CTA and digital subtraction angiography (DSA) studies were performed on patients with initial onset of SAH less than three days. CTA and DSA as well as the CTP parameters such as cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time-to-peak (TTP) were acquired and analyzed. The relationship of CTA and CTP measurements was assessed in these acute SAH patients.
  
  
  RESULTS
  CTP techniques were used to achieve the perfusion maps of the whole brain in patients with acute SAH. Compared to the control group, mean CBF value was significantly lower while both MTT and TTP values were significantly higher in SAH group (all p<0.05). Further analysis revealed that mean CBF in patients with CVS, sCVS, Fisher III-IV and Hunt-Hess III-V significantly decreased when compared to patients with nCVS, asCVS, Fisher I-II and Hunt-Hess I-II (p<0.05). Furthermore both MTT and TTP values were also significantly reduced in patient with CVS, sCVS, Fisher III-IV and Hunt-Hess III-V (p<0.05).
  
  
  CONCLUSIONS
  The study demonstrated that changes of microcirculation in patients with SAH could be assessed by whole-brain CTP. CTP combined with CTA could detect both macroscopic evident vasospasm on CTA and alterations of microcirculation on CTP. Mean CBF was significantly lower in patients with SAH.
authors.affiliation: Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, PR China.
authors.forename: He
authors.initials: H
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Shu
authors.initials: S
authors.lastname: Li
authors.forename: Chuansheng
authors.initials: C
authors.lastname: Liang
authors.forename: Ke
authors.initials: K
authors.lastname: Xu
authors.forename: Songbai
authors.initials: S
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D001776:Blood Circulation Time; D001810:Blood Volume; D002533:Cerebral Angiography / Q000379:methods*; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D036542:Tomography, Spiral Computed; D020301:Vasospasm, Intracranial / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*
keywords: CT angiography; Cerebral vasospasm; Subarachnoid hemorrhage; Whole-brain CT perfusion imaging