PT - JOURNAL ARTICLE AU - Takashi Ochi AU - Kenji Shimizu AU - Yoshifumi Yasuhara AU - Toshirou Shigesawa AU - Teruhito Mochizuki AU - Junpei Ikezoe TI - Curved Planar Reformatted CT Angiography: Usefulness for the Evaluation of Aneurysms at the Carotid Siphon DP - 1999 Jun 01 TA - American Journal of Neuroradiology PG - 1025--1030 VI - 20 IP - 6 4099 - http://www.ajnr.org/content/20/6/1025.short 4100 - http://www.ajnr.org/content/20/6/1025.full SO - Am. J. Neuroradiol.1999 Jun 01; 20 AB - BACKGROUND AND PURPOSE: Three-dimensional CT angiography uses the data obtained on a contrast-enhanced CT brain scan to generate 3D images of the intracranial vasculature. We describe the methodology of curved planar reformatting (CPR) for CT angiography and characterize its usefulness in the evaluation of aneurysms at the carotid siphon, comparing it with the shaded surface display technique (SSD).METHODS: Eighty-seven patients with suspected intracranial aneurysms at CT angiography were examined by conventional cerebral angiography, and the patients with aneurysm(s) at the carotid siphon were selected for study. For these patients, the visibility of the neck and fundus of the aneurysms on CT angiograms was compared for those obtained with SSD and those with CPR, and observer reproducibility was evaluated with the κ statistic.RESULTS: Eighteen patients were confirmed to have an aneurysm at the carotid siphon on conventional angiograms. Seventeen aneurysms were depicted at CT angiography with SSD; 18 aneurysms with CPR. The number of visible aneurysmal necks and fundi was nine and 12, respectively, with SSD; 18 and 18, respectively, with CPR.CONCLUSION: CPR allows better demonstration of the body and neck of an aneurysm at the carotid siphon, which has a tortuous course and is surrounded by complex bony structures. CPR may be a useful adjunct for the evaluation of aneurysms in this region.