Hemodynamics in a lethal basilar artery aneurysm just before its rupture.

BACKGROUND AND PURPOSE Hemodynamics is thought to play an important role in the mechanisms of cerebral aneurysm initiation, progression, and rupture. The purpose of this study was to present a hemodynamic study of a cerebral aneurysm immediately before its rupture to assess whether previously identified hemodynamic characteristics would classify this aneurysm in the high-risk category. MATERIALS AND METHODS A patient-specific computational fluid dynamics model was constructed from 3D rotational angiographic images acquired just hours before the aneurysm had ruptured. A pulsatile flow simulation was carried out, and the hemodynamics characterized by the concentration of the inflow jet, the size of the flow impingement region, and the complexity and stability of the flow pattern. RESULTS We found that the aneurysm had a concentrated inflow jet that impacted onto a small region of the dome of the aneurysm and created a complex, unstable flow pattern. CONCLUSIONS This study supports the proposition that hemodynamic characteristics derived from image-based computational models can be used to identify cerebral aneurysms at high risk for rupture.