Impact of temporary common carotid artery strangulation on hemodynamics during surgical clipping of middle cerebral bifurcation aneurysms

Intracranial aneurysms (IAs) involve weakening and abnormal ballooning of blood vessel walls. To safely perform surgical clipping on IAs, reducing aneurysmal pressure is crucial. While “temporary clipping” has conventionally been a fundamental technique in aneurysm-clipping surgery, it presents several challenges. In response, we suggested and investigated a new method termed “common carotid artery (CCA) temporary strangulation,” which involves the temporary strangulation of the ipsilateral common carotid artery (CCA) to decrease pressure in the middle cerebral artery (MCA) aneurysms. This study utilized computational fluid dynamics simulations with SimVascular, incorporating large-scale vascular geometries extending from the aorta to the circle of Willis. The boundary conditions were established using a pulsatile inlet flow rate and an outlet condition based on the resistance–capacitance–resistance Windkessel model, with CCA strangulation modeled at 0%, 75%, 85%, and 95%. Our results indicate that CCA strangulation significantly reduces ipsilateral MCA aneurysmal pressure and blood flow in the second segment of the MCA (M2). Specifically, at 95% CCA strangulation, the mean aneurysmal pressure decreased by 50%, accompanied by a 50% reduction in blood flow. Furthermore, our analysis indicates that the anterior communicating artery plays a critical role in modulating changes in aneurysmal pressure. A regression model that used the reduction in M2 segment velocity as a predictor for aneurysmal pressure achieved a high coefficient of determination, suggesting its reliability and clinical applicability. These findings suggest that CCA temporary strangulation could considerably enhance surgical safety by effectively managing intra-aneurysmal pressure, providing a viable tool for patient-specific surgical strategies.