Identification of the inflow zone of unruptured cerebral aneurysms: comparison of 4D flow MRI and 3D TOF MRA data

• Published in: American journal of neuroradiology : AJNR 2014-07, Vol.35 (7), p.1363-1370
• Main Authors: Futami, K, Sano, H, Misaki, K, Nakada, M, Ueda, F, Hamada, J
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Algorithms; Aneurysm, Ruptured - pathology; Aneurysm, Ruptured - physiopathology; Blood Flow Velocity; Cerebral Angiography - methods; Cerebrovascular Circulation; Female; Humans; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Imaging, Three-Dimensional - methods; Interventional; Intracranial Aneurysm - pathology; Intracranial Aneurysm - physiopathology; Magnetic Resonance Angiography - methods; Male; Middle Aged; Reproducibility of Results; Sensitivity and Specificity
• ISSN: 0195-6108; 1936-959X
• DOI: 10.3174/ajnr.a3877

The hemodynamics of the inflow zone of cerebral aneurysms may be a key factor in coil compaction and recanalization after endovascular coil embolization. We performed 4D flow MR imaging in conjunction with 3D TOF MRA and compared their ability to identify the inflow zone of unruptured cerebral aneurysms. This series comprised 50 unruptured saccular cerebral aneurysms in 44 patients. Transluminal color-coded 3D MRA images were created by selecting the signal-intensity ranges on 3D TOF MRA images that corresponded with both the luminal margin and the putative inflow. 4D flow MR imaging demonstrated the inflow zone and yielded inflow velocity profiles for all 50 aneurysms. In 18 of 24 lateral-projection aneurysms (75%), the inflow zone was located distally on the aneurysmal neck. The maximum inflow velocity ranged from 285 to 922 mm/s. On 4D flow MR imaging and transluminal color-coded 3D MRA studies, the inflow zone of 32 aneurysms (64%) was at a similar location. In 91% of aneurysms whose neck section plane angle was