title: Active bleeding in acute subarachnoid hemorrhage observed by multiphase dynamic-enhanced CT.
abstract: OBJECTIVE
  Acute SAH is reportedly associated with rebleeding from aneurysms, and recent advances in imaging technology allow us to visualize active bleeding in SAH cases. This study aimed to retrospectively investigate the incidence and characteristics of active bleeding in patients with spontaneous SAH by using multiphase dynamic-enhanced CT.
  
  
  METHODS
  We retrospectively surveyed a series of patients with SAH who underwent CTP with 18-phase dynamic enhancement and confirmed the presence of extravasated contrast medium in the source image. We compared clinical features between 2 groups of patients with and without extravasation.
  
  
  RESULTS
  Active bleeding was observed with increasing enhancement in 25.5% (13/51) of patients. All patients with extravasation were in Claassen grade 3 or 4 and WFNS grades 3, 4, or 5. The other group without extravasation included patients in all grades. A significant difference was observed in Claassen grade, WFNS grade, and increase of hematomas in follow-up CT (P < .05, for each) between the 2 groups. All CTP results of patients with extravasation were obtained within 2 hours of the onset of symptoms of SAH (P < .05). There was no significant difference in mortality at 14 days between the 2 groups (P = .128).
  
  
  CONCLUSIONS
  A high incidence of active bleeding (25.5%) was detected by multiphase dynamic-enhanced CT in patients with acute SAH. These results indicate that an awareness of active bleeding in patients with SAH has the potential to affect the treatment strategy.
authors.affiliation: Department of Radiology, Tokyo Women’s Medical University Medical Center East, Tokyo, Japan. kasuzuki-rad@umin.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: N
authors.initials: N
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Morita
authors.forename: H
authors.initials: H
authors.lastname: Machida
authors.forename: E
authors.initials: E
authors.lastname: Ueno
authors.forename: H
authors.initials: H
authors.lastname: Kasuya
mesh_terms: D000368:Aged; D002533:Cerebral Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*