Clot Composition Profiling in Large Vessel Occlusion Stroke Via Radiomics

OBJECTIVE: Clot composition may offer insights into the mechanism of ischemic stroke. Radiomics, a noninvasive imaging technique, enables tissue characterization through radiomic features (RFs). We aimed to evaluate clot composition using radiomics on non-contrast computed tomography (NCCT). METHODS: In the first phase, we conducted a prospective study comparing RFs with histopathology in thrombi retrieved via mechanical thrombectomy (MT). Thrombi were imaged using micro-computed tomography (micro-CT) and analyzed histologically. Matched micro-CT and histological slices identified red blood cells (RBCs) and fibrin-rich regions. RFs were extracted, and multivariate logistic regression identified features associated with each component. Spearman's correlation was used to assess associations between RFs and percentage composition. The same clots were localized on pre-MT NCCT, and RFs were extracted. Micro-CT and NCCT RFs were correlated to enable histology-informed interpretation. Receiver operating characteristic analysis evaluated the ability of NCCT RFs to discriminate clot composition. In the second phase, radiomics was applied to a retrospective NCCT dataset from patients with ischemic stroke with varying etiologies. RESULTS: Ten thrombi were analyzed using micro-CT. Total energy (odds ratio [OR] = 1.35, 95% confidence interval [CI] = 1.20-1.54, p < 0.001) and large dependence high gray level emphasis (OR = 1.18, 95% CI = 1.07-1.32, p = 0.01) were associated with RBCs and correlated with >70% RBCs composition on NCCT (Rho = 0.752 and Rho = 0.815). Subsequently, 150 NCCT scans were analyzed, including 50 cardioembolic, 50 large artery atherosclerosis (LAA), and 50 cryptogenic strokes. Radiomic analysis indicated RBCs-predominant composition in 72% of cardioembolic, 30% of LAA, and 50% of cryptogenic clots. INTERPRETATION: Radiomics is a promising, noninvasive technique for characterizing clot composition. ANN NEUROL 2026;99:1179-1188.