title: Subtraction CT angiography with controlled-orbit helical scanning for detection of intracranial aneurysms.
abstract: OBJECTIVE
  Our goal was to evaluate the utility of subtraction three-dimensional CT angiography for the detection of intracranial aneurysms.
  
  
  METHODS
  Thirty-six patients with intracranial aneurysms were examined using newly devised controlled-orbit helical scanning and conventional angiography. Three-dimensional CT angiograms and subtraction 3-D CT angiograms were compared with conventional angiograms for their characterization of intracranial aneurysms.
  
  
  RESULTS
  Fifty aneurysms were depicted on conventional angiograms, of which 48 (96%) were seen on the 3-D CT angiograms. Three-dimensional CT angiography was superior or equivalent to conventional angiography for depicting the shape, direction, and location of 33 (66%) of 50 aneurysms; however, it was often less useful than conventional angiography in delineating intracranial aneurysms adjacent to bone. Subtraction 3-D CT angiograms were obtained in 32 patients with a total of 46 aneurysms (in four cases, aneurysms were not depicted owing to excessive motion artifacts), and were superior or equivalent to conventional angiograms in all 46 cases.
  
  
  CONCLUSIONS
  Subtraction 3-D CT angiography with the use of controlled-orbit helical scanning is effective in the detection of intracranial aneurysms.
authors.affiliation: Department of Radiology, National Cardiovascular Center, Suita-city, Osaka, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Imakita
authors.forename: Y
authors.initials: Y
authors.lastname: Onishi
authors.forename: T
authors.initials: T
authors.lastname: Hashimoto
authors.forename: S
authors.initials: S
authors.lastname: Motosugi
authors.forename: S
authors.initials: S
authors.lastname: Kuribayashi
authors.forename: M
authors.initials: M
authors.lastname: Takamiya
authors.forename: N
authors.initials: N
authors.lastname: Hashimoto
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: T
authors.initials: T
authors.lastname: Sawada
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction / Q000295:instrumentation*; D016477:Artifacts; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D002533:Cerebral Angiography / Q000295:instrumentation*; D002536:Cerebral Arteries / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*