Irregular pulsation of intracranial unruptured aneurysm detected by four-dimensional CT angiography is associated with increased estimated rupture risk and conventional risk factors.

IAs with irregular pulsation are associated with larger size, irregular-shape, and non-ICA origin, and have more than a 6-fold higher estimated 1- and 5-year rupture risk than aneurysms without irregular pulsation. Irregular pulsation should be validated in future longitudinal studies to determine its predictive value for aneurysm growth and rupture.