Intracranial aneurysm risk scores, hemodynamics and vessel wall enhancement values

Vessel wall enhancement (VWE) in contrast-enhanced magnetic resonance
imaging (MRI) is a potential biomarker for intracranial aneurysm (IA) risk
stratification. In this study, we investigated the relationship between
VWE features, risk metrics, morphology, and hemodynamics in 41 unruptured
aneurysms. We reconstructed the IA geometries from MR angiography and
mapped pituitary stalk-normalized MRI intensity on the aneurysm surface
using an in-house tool. For each case, we calculated the maximum intensity
(CRstalk) and IA risk (via size and the rupture resemblance score-RRS). We
performed correlation analysis to assess relationships between CRstalk and
IA risk metrics (size and RRS), as well as each parameter encompassed in
RRS, i.e. aneurysmal Size Ratio (SR), normalized wall shear stress (WSS),
and oscillatory shear index (OSI). We found that CRstalk had a strong
correlation (Pearson correlation coefficient, PCC=0.630) with size and a
moderate correlation (PCC=0.472) with RRS, indicating an association
between VWE and IA risk. Furthermore, CRstalk had a weak negative
correlation with normalized WSS (PCC=-0.320) and a weak positive
correlation with SR (PCC= 0.390). Local voxel-based analysis showed only a
weak negative correlation between normalized WSS and contrast-enhanced MRI
signal intensity (PCC=-0.240), suggesting that if low normalized WSS
induces enhancement-associated pathobiology, the effect is not localized.