Angiography is gold standard technique as preoperative examination for unruptured aneurysmal surgery. Neurosurgeons have observed the unexpected irregular shape and size of the aneurysmal dome and neck in many cases of unruptured cerebral aneurysms during aneurysmal microsurgery, and known the discrepancy between the findings of angiography and operative view. We could not find out the report described the preoperative evaluation of outer-wall (contour) of aneurysm. In the present study, we attempted to evaluate the outer-wall of an unruptured cerebral aneurysm using three-dimensional CT cisternogram (3D-CTC) to provide useful preoperative information. The study was performed on three cases of unruptured cerebral aneurysm that were identified incidentally by MR angiography. We performed three-dimensional CT aniography (3D-CTA) and 3D-CTC for each patient. In the present study, we visualized the contours of vessels and aneurysms using a 3D-CTC in three cases of unruptured cerebral aneurysm. We found the discrepancy between the 3D-CTC contour image and the intra-luminal image 3D-CTA image. This method may be useful for the decision of the surgical approach and have the potential to evaluate the anatomical structure of aneurysmal dome and neck preoperatively.</p
