Abstract： Objective:To investigate the predictive value of thrombus enhancement (TE) and thrombus permeability in cardioembolic thrombus with acute middle cerebral artery occlusion based on CT.Methods:The clinical and image data of 93 patients with acute middle cerebral artery occlusion who were admitted to the First Affiliated Hospital of Soochow University within 12 hours after onset from January 2020 to July 2022 were retrospectively analyzed. According to the TOAST criteria, the patients were divided into the cardioembolism (CE) group (43 cases) and the large artery atherosclerosis (LAA) group (50 cases). All patients received noncontrast CT and CT angiography, and then thrombus permeability [thrombus attenuation increase (TAI), void fraction (ε)] and TE were assessed. Independent sample t-test, Mann-Whitney U test and χ2 test were used in univariable analysis between two groups. Multivariable logistic regression analysis was used to explore the independent influencing factors for cardioembolic stroke and establish a logistic model. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to evaluate the predictive value of TAI, ε, TE and the logistic model in cardioembolic thrombus with acute middle cerebral artery occlusion. Results:There were statistically significant differences in sex, atrial fibrillation, hypertension, diabetes mellitus, smoking, baseline National Institutes of health stroke scale (NIHSS), TAI, ε and TE between the CE group and the LAA group ( P<0.05). Binary logistics regression analysis showed that TAI (OR=1.300, 95%CI 1.147-1.473, P<0.001), hypertension (OR=0.116, 95%CI 0.025-0.535, P=0.006) and baseline NIHSS (OR=1.165, 95%CI 1.040-1.304, P=0.008) were independent influencing factors for cardioembolic thrombus. The ROC curve indicated that the logistic model predicted cardioembolic thrombus with the highest AUC of 0.907 (95%CI 0.848-0.966). TE predicted cardioembolic thrombus with the highest sensitivity of 90.7%. Conclusion:TE and thrombus permeability have application value for predicting cardioembolic thrombus with acute middle cerebral artery occlusion based on CT.