title: Depiction of branch vessels arising from intracranial aneurysm sacs: Time-of-flight MR angiography versus CT angiography.
abstract: BACKGROUND
  To evaluate the sensitivity, specificity, and accuracy of time-of-flight MR angiography (MRA) compared with CT angiography (CTA) for detection of branch vessels arising from the intracranial aneurysm sac, using a 3-tesla MR scanner and an area detector CT scanner.
  
  
  METHODS
  Fifty patients with an intracranial aneurysm (25 patients with a branch vessel arising from the sac and 25 patients without) underwent rotational intraarterial digital subtraction angiography (rotational DSA), MRA, and CTA. The following six image sets were assessed using a 3-point scale for the existence of a branch vessel: (1) volume rendering with MRA (MRA-VR); (2) CTA-VR; (3) source images with MRA; (4) source images with CTA; (5) VR and source images with MRA ('MRA-VR+source images'); and (6) 'CTA-VR+source images'. Each set comprised the data of all 50 patients. Three radiologists then performed consensus review and calculated the sensitivity, specificity, and accuracy for MRA and CTA; rotational DSA was considered as the gold standard.
  
  
  RESULTS
  Higher accuracies were obtained in review using VR+source compared with both VR and source alone. In addition, higher accuracies were obtained in review using MRA compared with CTA. The highest accuracy of 0.96 was obtained for 'MRA-VR+source images'; in contrast, accuracy on 'CTA-VR+source images' was 0.86.
  
  
  CONCLUSIONS
  The results show that 3-tesla MRA is an ideal non-invasive imaging examination for detection of a branch vessel arising from an intracranial aneurysm sac. Higher accuracy, especially sensitivity, with MRA compared with CTA was found in ICA, but accuracy with MRA was same as that with CTA in MCA.
authors.affiliation: Department of Radiological Technology, University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. Electronic address: car6_pa2_rw@yahoo.co.jp.
authors.forename: Masami
authors.initials: M
authors.lastname: Goto
authors.affiliation: Department of Radiology, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kunimatsu
authors.affiliation: Department of Neurosurgery, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Shojima
authors.affiliation: Department of Radiology, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Harushi
authors.initials: H
authors.lastname: Mori
authors.affiliation: Department of Radiology, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Abe
authors.affiliation: Department of Radiology, Juntendo University, Tokyo, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Aoki
authors.affiliation: Department of Computational Diagnostic Radiology and Preventive Medicine, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Hayashi
authors.affiliation: Department of Radiology, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Gonoi
authors.affiliation: Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan.
authors.forename: Tosiaki
authors.initials: T
authors.lastname: Miyati
authors.affiliation: Department of Radiological Technology, University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ino
authors.affiliation: Department of Radiological Technology, University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Yano
authors.affiliation: Department of Neurosurgery, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Saito
authors.affiliation: Department of Radiology, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Kuni
authors.initials: K
authors.lastname: Ohtomo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D002533:Cerebral Angiography / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000000981:diagnostic imaging; D018810:Magnetic Resonance Angiography / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D008875:Middle Aged; D012680:Sensitivity and Specificity
keywords: Aneurysm; Angiography; Computed tomography; Time-of-flight; VR-rotational DSA