Efficacy of high-resolution cone-beam CT in the evaluation of perforators in vertebral artery dissection.

Introduction A major complication of internal coil trapping for vertebral artery dissection (VAD) is medullary infarction associated with perforator occlusion. Currently, higher spatial resolution imaging can be obtained with high-resolution cone-beam computed tomography (VASO CT), and the efficacy of perforator visualization adjacent to VAD was examined. Methods Eight patients who underwent internal coil trapping or stent-supported coil embolization underwent VASO CT to evaluate perforators around VAD. Visualization of perforators was compared with conventional digital subtraction angiography (DSA) and three-dimensional rotational angiography (3D-RA). Postoperative MRI was performed in all patients to investigate ischemic complications. The relationship between the perforators and the infarction was analyzed. Results Perforator visualization was much clearer on VASO CT than on 2D DSA or 3D-RA. It was sharp enough to identify each perforating artery. Medullary infarctions were detected in two cases. In these two cases, each ischemic lesion corresponded to the territory of a perforator that was well visualized on VASO CT. The axial view with adjoining tissue structures on VASO CT was useful to detect the territories of perforators. Conclusions VASO CT is an efficient modality for the detection and identification of perforators in the vicinity of VAD. It provides accurate anatomical information about the vertebrobasilar system that is useful for the treatment of unruptured VAD.