A Novel Application of Radiomics Analysis for Computational Fluid Dynamics Evaluation of Cerebral Aneurysms

PyRadiomics is a recently introduced automatic imaging tool for evaluating intensity-based texture descriptors and shape morphology. Due to intensity homogeneity in contrast-enhanced rotational angiography, radiomics analysis for intracranial aneurysms was previously limited to morphological evaluation. We propose a novel use of radiomics analysis to assess aneurysm intra-dome velocity distributions derived from computational fluid dynamics (CFD) simulations.

Catheter 3D rotational angiographic volumes from 68 aneurysms (29 ruptured) were analyzed. Steady-state CFD simulations were performed on segmented models, and intra-dome velocity distributions were extracted using mesh-independent isometric sampling. Velocity volumes were normalized for size and magnitude, converted to grayscale DICOM, and analyzed to extract 93 histogram and texture radiomics features. Uni- and multivariate analyses assessed these features for rupture status discrimination.

Radiomics analysis showed that ruptured aneurysms had significantly lower energy (P = 0.005) and entropy (P = 0.004), but higher skewness (P = 0.001), kurtosis (P < 0.001), and uniformity (P = 0.001) than unruptured ones. Texture analysis revealed lower contrast (P = 0.02) and gray-level variance (P = 0.02), but higher strength (P = 0.04). Ruptured aneurysms also showed greater clustering of low gray-level values, reflected by higher LowGrayLevelEmphasis (P = 0.001) and LargeAreaLowGrayLevelEmphasis (P = 0.01). Multivariate analysis achieved an AUC of 0.90 (sensitivity 0.86, specificity 0.85).

Automatic histogram and texture analysis of intra-dome velocity using radiomics showed strong rupture status discrimination. Ruptured aneurysms exhibited pattern uniformity with reduced gray-level variability, and fewer high-intensity areas. This novel approach to CFD volumetric evaluation, extending radiomics use beyond angiographic analysis, provides insights into rupture characteristics, and opens novel and promising avenues of future research.