Cerebral Aneurysm

Cerebral aneurysms are a life-threatening condition and too simplified models are currently used to decide on treatment or regular follow-up. Risk of aneurysm growth or rupture is difficult to assess and hemodynamic factors are recently considered as new imaging biomarkers. 4D-flow MRI was employed for the comprehensive in-vivo analysis of hemodynamics and its relationship to size and morphology of different intracranial aneurysms (IA). 4D flow MRI demonstrated the influence of lesion size and morphology on aneurysm hemodynamics suggesting the potential of 4D-flow MRI to assist in the classification of individual aneurysms (1).

We however, that standard 4D flow MRI with single-venc gradients suffers from either velocity aliasing or low velocity to noise ratio. Therefore, we started using dual-venc 4D flow MRI (2) in a new group of patients. We applied and investigated the benefits of using kt-GRAPPA accelerated dual-venc 4D flow MRI in 12 patients who presented with cerebral aneurysm between 4 and 12mm (smallest and largest dimension). When applied to patients with cerebral aneurysms, we could show that dual-venc demonstrated higher sensitivity to slower velocity values and provided less noisy data. Future longitudinal studies and correlation with aneurysm risk factors or aneurysm growth/rupture are required to evaluate the utility of hemodynamic markers for improved risk assessment and therapy planning.

Funding: German Research Foundation SCHN 1170/2-1 (2012 – 2014), SIR Research Pilot Grant (2012 – 2013), NIH 1R21NS106696-01 (2018 – 2020)

Publications:

Schnell S, Ansari SA, Vakil P, Wasielewski M, Carr ML, Hurley MC, et al. Three-dimensional hemodynamics in intracranial aneurysms: Influence of size and morphology. Journal of Magnetic Resonance Imaging. 2014;39:120-131