Use of a C-arm system to generate true three-dimensional computed rotational angiograms: preliminary in vitro and in vivo results.

PURPOSE 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.