Article Text
Abstract
Introduction It is unknown why aneurysm rupture occurs at a specific location in the aneurysm wall.
Aim of Study Perform a comprehensive analysis of brain aneurysms. This includes aneurysmal wall enhancement (AWE), computational fluid dynamics (CFD) and finite element analysis (FEA) of different areas of the aneurysm.
Methods Forty-seven unruptured saccular aneurysm were included in the study. 3T high resolution vessel wall imaging was performed. 3D Segmentations of the aneurysms were generated with 3D Slicer to assess: AWE using post-contrast signal intensity (SI) heatmaps; Wall Tension (WT) calculated from FEA; time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and wall shear stress gradient (WSSG) from CFD. A detailed compartmental analysis was performed.
Results Eighteen aneurysms were irregular and eleven had blebs. WT, TAWSS, and WSSG were higher in the neck compared to the dome (p<0.001, p=0.02 and p<0.001, respectively). Conversely, AWE and OSI were higher in the dome compared to the neck (p=0.01 and p=0.03, respectively). In aneurysms with blebs, WT, WSSG, and AWE were significantly different between the bleb, neck, and aneurysm body (p<0.001, p=0.04 and p=0.03, respectively). Blebs had the highest AWE in the aneurysm. However, the lowest points of WT and WSSG in the aneurysms were in the bleb.
Conclusion A comprehensive morphomechanical assessment may identify high risk areas of rupture within the aneurysm. Unstable areas, such as blebs, had a high AWE and low WSSG and WT. The morphomechanical features also differed in the aneurysm neck compared to the body.
Disclosure of Interest Nothing to disclose