title: Detection of aneurysmal subarachnoid hemorrhage 3 months after initial bleeding: evaluation of T2* and FLAIR MR sequences at 3 T in comparison with initial non-enhanced CT as a gold standard.
abstract: OBJECTIVE
  To investigate the ability of T2* and fluid-attenuated inversion recovery (FLAIR) MR sequences to detect hemosiderin deposition 3 months after aneurysmal subarachnoid hemorrhage (SAH) in comparison with early non-enhanced CT (NECT) as a gold standard.
  
  
  METHODS
  From September 2008 through May 2013, patients with aneurysmal SAH were included if a NECT less than 24 h after the onset of symptoms showed a SAH, and MRI, including T2* and FLAIR sequences, was performed 3 months later. All aneurysms were treated endovascularly. NECT and MR sequences were blindly analyzed for the presence of SAH (NECT) or hemosiderin deposition (MRI). When positive, details of the spatial distribution of SAH or hemosiderin deposits were noted. Sensitivities were calculated for each patient. Sensitivities, specificities, and positive predictive values (PPVs) were calculated for each location.
  
  
  RESULTS
  Forty-nine patients (mean age 52.9 years) were included. Bleeding-related patterns were identified in 43 patients (87.8%) on T2* and 10 patients (20.4%) on FLAIR. T2* was highly predictive of the location of the initial hemorrhage, especially in the Sylvian cisterns (PPVs 95% and 100%) and the anterior interhemispheric fissure (PPV 90%).
  
  
  CONCLUSIONS
  The T2* sequence can detect and localize a previous SAH a few months after aneurysmal bleeding.
authors.affiliation: Department of Radiology, Maison Blanche Hospital, Reims cedex, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Mulé
authors.affiliation: Department of Radiology, Maison Blanche Hospital, Reims cedex, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Soize
authors.affiliation: Department of Radiology, Maison Blanche Hospital, Reims cedex, France.
authors.forename: Azzedine
authors.initials: A
authors.lastname: Benaissa
authors.affiliation: Department of Radiology, Maison Blanche Hospital, Reims cedex, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Portefaix
authors.affiliation: Department of Radiology, Maison Blanche Hospital, Reims cedex, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Pierot
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography / Q000379:methods*; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging* / Q000601:surgery; D002550:Cerebral Veins / Q000000981:diagnostic imaging; D057510:Endovascular Procedures; D005260:Female; D006485:Hemosiderin / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012015:Reference Standards; D015203:Reproducibility of Results; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D006485:Hemosiderin
keywords: Aneurysm; Hemorrhage; Subarachnoid