title: Clinical usefulness of unsubtracted 3D digital angiography compared with rotational digital angiography in the pretreatment evaluation of intracranial aneurysms.
abstract: OBJECTIVE
  Three-dimensional digital subtraction angiography (DSA) is useful as a supplement to 2D DSA in the pretreatment evaluation of intracranial aneurysms. However, the clinical efficacy of 3D digital angiography (DA) that is generated from unsubtracted rotational images has not been established. The purpose of this study was to assess whether 3D DA provides additional useful information to that of rotational DA in the preoperative evaluation of intracranial aneurysms.
  
  
  METHODS
  This prospective study comprised 23 patients (age range, 37-83 years) with ruptured aneurysms who underwent angiography. Two radiologists independently evaluated the rotational DA images and the maximum intensity projection, shaded surface display, and volume-rendering 3D DA images, in combination with 2D DSA images. A four-point scoring system was used to evaluate aneurysm detection and delineation. Referring neurosurgeons were questioned as to whether the information obtained with 3D DA was useful for treatment decisions.
  
  
  RESULTS
  Thirty aneurysms were confirmed by surgery or endovascular treatment. In detection and delineation of the 30 confirmed aneurysms, overall mean scores were highest with volume-rendering 3D DA and lowest with rotational DA. Compared with rotational DA, volume-rendering 3D DA demonstrated 27 additional findings in 14 (47%) of 30 aneurysms: detection of an aneurysm (n = 2), and delineation of aneurysm neck, shape, and relationship to adjacent arteries (n = 25). The information provided by 3D DA was useful for following treatment in five (22%) of 23 patients.
  
  
  CONCLUSIONS
  In the preoperative evaluation of intracranial aneurysms, 3D DA can provide additional useful information to that of rotational DA.
authors.affiliation: Department of Radiology, Amakusa Medical Center, 854-1 Kameba, Hondo, Kumamato 863-0046, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Hirai
authors.forename: Yukunori
authors.initials: Y
authors.lastname: Korogi
authors.forename: Kenji
authors.initials: K
authors.lastname: Suginohara
authors.forename: Ken
authors.initials: K
authors.lastname: Ono
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nishi
authors.forename: Shozaburo
authors.initials: S
authors.lastname: Uemura
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yamura
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Yamashita
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017542:Aneurysm, Ruptured / Q000601:surgery* / Q000628:therapy; D015901:Angiography, Digital Subtraction; D002533:Cerebral Angiography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000601:surgery* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity