Purpose Rupture risk assessment of intracranial aneurysms using non-invasive MRI is an active area of research, particularly in the realm of intra-aneurysmal flow modeling with 4D Flow MRI and imaging of wall tracer uptake and permeability using DCE-MRI. While several studies have examined these parameters independently, no study has thus far examined them simultaneously in the same patient. In this work we report the comparison of intra-aneurysmal hemodynamic parameters with wall permeability modeling within the same patient.
Materials and methods With IRB approval we acquired 4D Flow Phase-Contrast MRI data and DCE-MRI in 8 consecutive, angiographically-confirmed saccular cerebral aneurysms. We quantified contrast agent leakage rate (Ktrans) through the aneurysm wall using Tofts’s model using a previously reported method.1 Images were post-processed using in-house software to calculate hemodynamic parameters wall shear stress (WSS),2 and permeability parameter Ktrans. Mean WSS and Ktrans were cross-sectionally compared across all aneurysms. We further used linear regression to compare hemodynamic and wall-permeability parameters.
Results We found no statistically significant correlation between mean WSS and Ktrans (R2=0.0012, p=0.93). Similarly there was no correlation between mean velocity and Ktrans (R2=0.020, p=0.73), as well as aneurysm diameter and Ktrans (R2=0.0050, p=0.87).
Conclusion In this study we did not find significant correlation between intra-aneurysmal hemodynamics and wall-permeability. Their lack of inter-correlation suggests they may contribute unique information about aneurysm risk profile and serve as independent markers of rupture risk.
Vakil P, Ansari SA, Cantrell CG, et al. Quantifying intracranial aneurysm wall permeability for risk assessment using dynamic contrast-enhanced MRI: A pilot study. American Journal of Neuroradiology 2015;36:953–59.
Schnell S, Ansari SA, Vakil P, et al. Three-dimensional hemodynamics in intracranial aneurysms: Influence of size and morphology. Journal of Magnetic Resonance Imaging 2014;39:120–131.
Disclosures M. Pan: None. P. Vakil: None. A. Vali: None. M. Markl: None. S. Schnell: None. S. Ansari: None.