Objective: The purpose of this study was to evaluate large intracranial aneurysms by contrast-enhanced 3D MRI.
Materials and methods: Eleven patients, nine women and two men, were examined. The aneurysms involved the internal carotid artery in seven patients, the middle cerebral artery in one, the basilar artery in two, and the posterior cerebral artery in one. Contrast-enhanced 3D MR images were obtained using FLASH (fast low angle shot) on a 1.5 T system. We obtained axial images first, then sagittal and coronal images by multiplanar reconstruction. Those images were reviewed for comparison with conventional and MR angiography.
Results: We could easily evaluate the true aneurysmal size, the intraaneurysmal constitution (patent lumen and intraluminal thrombus), and the detailed relationship of the aneurysm to the surrounding vascular and neural structures. Except for the cavernous internal carotid artery, we could identify the aneurysmal neck by carefully observing axial, sagittal, and coronal images. In addition, the progression of intraaneurysmal thrombosis and the patency of the parent arterial lumen after the endovascular treatment were well appreciated.
Conclusion: We consider that 3D MRI appears to be useful for evaluation of the large intracranial aneurysm.