Objectives <p>This study aimed to assess the agreement between carotid Doppler ultrasound (CDU) and high-resolution magnetic resonance imaging (HRMRI) in the evaluation of extracranial internal carotid artery dissection (EICAD), and to explore the association between sonographic features and ischemic stroke.</p> Methods <p>Patients with suspected EICAD who underwent both CDU and HRMRI between January 2015 and June 2022 were retrospectively enrolled. Agreement between the two imaging modalities was evaluated for the detection of double lumen, intimal flap, intramural hematoma (IMH), intraluminal thrombus, dissecting aneurysm, and luminal stenosis. Patients were subsequently categorized into stroke and non-stroke groups according to diffusion-weighted imaging (DWI) results. Multivariable logistic regression analyses were performed to examine associations between clinical and sonographic characteristics and ischemic stroke. Propensity score matching (PSM), as well as subgroup and interaction analyses, were conducted to assess the robustness of the findings.</p> Results <p>A total of 153 patients with confirmed EICAD were included. CDU and HRMRI demonstrated excellent agreement for the detection of IMH, intraluminal thrombus, and luminal stenosis; good agreement for intimal flap and dissecting aneurysm; and poor agreement for double lumen. Multivariable logistic regression analysis showed that IMH and intraluminal thrombus detected by CDU were independently associated with ischemic stroke. These associations remained statistically significant after propensity score matching. Subgroup and interaction analyses demonstrated consistent associations across different patient subgroups.</p> Conclusion <p>IMH and intraluminal thrombus detected on CDU were associated with ischemic stroke in patients with EICAD. CDU may provide useful imaging information in the evaluation of patients with suspected EICAD, particularly for identifying features associated with ischemic stroke.</p>