Official websites use. Share sensitive information only on official, secure websites. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Although wall shear stress WSS has long been considered a critical indicator of intracranial aneurysm rupture, there is still no definite conclusion as to whether a high or a low WSS results in aneurysm rupture.
The reason may be that the effect of WSS direction has not been fully considered. The objectives of this study are to investigate the magnitude of WSS WSS and its divergence on the aneurysm surface and to test the significance of both in relation to the aneurysm rupture.
Our results revealed that if high WSS is stretching aneurysm luminal surface, and the stretching region is concentrated, the aneurysm is under a high risk of rupture. It seems that, by considering both direction and magnitude of WSS, WSSD may be a better indicator for the risk estimation of aneurysm rupture Rupture of intracranial aneurysm IA is a widely studied topic.
Though the rupture rate of IAs is not high [ 4 ], it causes serious consequences including disability and mortality [ 5 ]. On the other hand, current treatments of IAs also carry a risk. Thus, accurate assessment of IA rupture is essential for clinicians to balance the risk of surgery against the risk of natural IAs rupture [ 6 , 7 ].
Research into risk factor for IAs rupture has been reported for many years, including the effect of aneurysm size, geometry, location, and others [ 8 , 9 ]. Large-sized aneurysms were considered to be under high risk of rupture. However, recent studies have shown that many ruptured aneurysms were small in size [ 9 , 10 ]. In order to improve estimations of risk based on medical images, multiple geometric factors were proposed, such as aspect ratio AR , size ratio SR , and other factors.
