title: Diagnosis of unruptured intracranial aneurysms: 3T MR angiography versus 64-channel multi-detector row CT angiography.
abstract: OBJECTIVE
  We compared 3-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA) using a 3-tesla (T) MR unit with 64-channel multi-detector row computed tomographic angiography (64-MDCTA) for detection and characterization of angiographically proven unruptured intracranial aneurysms.
  
  
  METHODS
  Thirty-eight patients with 47 aneurysms and 8 patients without aneurysms underwent 3T, 3D TOF MRA; 64-MDCTA; and intra-arterial angiography. As a first study, 3 radiologists blinded to pertinent clinical information independently reviewed MRA and CTA images. We evaluated diagnostic accuracy using an alternative free-response receiver operating characteristic (AFROC) analysis and evaluated the sensitivity and specificity of each technique. Next, 2 radiologists used volume-rendering images generated from MRA or CTA data to evaluate the morphology of the 47 aneurysms detected, and MRA and CTA results were compared. Three-dimensional digital angiography (DA) images were used as the standard of reference.
  
  
  RESULTS
  On the AFROC analysis, the value of the mean area under the AFROC curve (A(1)) was 0.91 for both modalities. Mean sensitivity of 89% and specificity of 76% for MRA were not significantly different from sensitivity of 87% and specificity of 79% for CTA. Therefore, when used to evaluate aneurysmal morphology, both modalities appear satisfactory for determining these vascular anomalies.
  
  
  CONCLUSIONS
  Three-tesla, 3D TOF MRA and 64-MDCTA are excellent modalities with high diagnostic accuracy for evaluating unruptured intracranial aneurysms and no significant difference between them in diagnostic performance.
authors.affiliation: Department of Radiology, Ehime University School of Medicine, Ehime, Japan. hirazka@m.ehime-u.ac.jp
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Hiratsuka
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Miki
authors.forename: Ikuko
authors.initials: I
authors.lastname: Kiriyama
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kikuchi
authors.forename: Shizue
authors.initials: S
authors.lastname: Takahashi
authors.forename: Ichiro
authors.initials: I
authors.lastname: Matsubara
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sadamoto
authors.forename: Teruhito
authors.initials: T
authors.lastname: Mochizuki
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002533:Cerebral Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000473:pathology; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods*