title: Visualization of extracranial-intracranial bypass using multidetector-row helical computed tomography angiography.
abstract: OBJECTIVE
  The advent of multidetector-row computed tomography (MDCT) has enabled images with good spatial resolution to be obtained over a wide range in a short scanning time. Our purpose was to determine whether CT angiography using the MDCT system could effectively depict extracranial-intracranial (EC-IC) bypass routes.
  
  
  METHODS
  Helical CT angiography was performed using an MDCT scanner in 12 patients who had undergone EC-IC bypass surgery: 10 patients had undergone superficial temporal artery-middle cerebral artery (MCA) anastomosis, 1 patient had undergone an encephaloduroarteriosynangiosis procedure for the treatment of moyamoya disease, and 1 patient had undergone an external carotid artery-MCA anastomosis using a graft. The resulting CT angiograms were visually evaluated for their depiction of the EC-IC bypass route. Conventional angiograms were available for comparison in all 12 patients.
  
  
  RESULTS
  The EC-IC bypass was visualized to be patent at the site of anastomosis in all 12 patients. Branches of the MCA secondary or more to those connected to a donor artery were demonstrated in 9 patients, whereas MCA branches immediately distal to the anastomosis were demonstrated in 3 patients. The CT angiography findings corresponded well with the conventional angiography findings in all patients.
  
  
  CONCLUSIONS
  Helical CT angiography using the MDCT technique is an effective method for visualizing EC-IC bypass routes.
authors.affiliation: Department of Radiology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan. tsuchiyak-kyr@umin.ac.jp
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Chinatsu
authors.initials: C
authors.lastname: Aoki
authors.forename: Shichiro
authors.initials: S
authors.lastname: Katase
authors.forename: Junichi
authors.initials: J
authors.lastname: Hachiya
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Shiokawa
mesh_terms: D000328:Adult; D000368:Aged; D000714:Anastomosis, Surgical; D001157:Arterial Occlusive Diseases / Q000175:diagnosis / Q000601:surgery; D002548:Cerebral Revascularization; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000601:surgery; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013699:Temporal Arteries / Q000000981:diagnostic imaging / Q000601:surgery; D036542:Tomography, Spiral Computed; D016896:Treatment Outcome; D014654:Vascular Patency / Q000502:physiology