title: Use of a C-arm system to generate true three-dimensional computed rotational angiograms: preliminary in vitro and in vivo results.
abstract: OBJECTIVE
  To evaluate the potential use of a C-arm mounted X-ray image intensifier (XRII) system to generate three-dimensional computed rotational angiograms during interventional neuroradiologic procedures.
  
  
  METHODS
  A clinical angiographic system was modified to allow collection of sufficient views during selective intraarterial contrast injections for CT reconstruction of a 15 x 15 x 15-cm3 volume. Image intensifier distortion and C-arm instabilities were corrected by using image-based techniques. The impact of the pulsatile nature of the vessels during image data acquisition and of the presence of bone on the 3-D reconstructions was investigated by generating 3-D reconstructions of an anesthetized 20-kg pig and of a human skull phantom.
  
  
  RESULTS
  A sequence of images sufficient for 3-D reconstruction was acquired in less than 5 seconds. Image intensifier distortion and C-arm instabilities were corrected to subpixel accuracy (0.035 mm and 0.07 mm, respectively). Both the intracranial vessels of the pig and the small, high-contrast structures in the skull were reconstructed with negligible artifacts.
  
  
  CONCLUSIONS
  Using a C-arm mounted XRII system, computed rotational angiography can provide true 3-D images of diagnostic quality.
authors.affiliation: Department of Medical Biophysics, University of Western Ontario, London, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Fahrig
authors.forename: A J
authors.initials: AJ
authors.lastname: Fox
authors.forename: S
authors.initials: S
authors.lastname: Lownie
authors.forename: D W
authors.initials: DW
authors.lastname: Holdsworth
mesh_terms: D000818:Animals; D016477:Artifacts; D001921:Brain / Q000098:blood supply*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging; D002533:Cerebral Angiography / Q000295:instrumentation*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D066298:In Vitro Techniques; D019047:Phantoms, Imaging; D012680:Sensitivity and Specificity; D013552:Swine; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*; D014963:X-Ray Intensifying Screens