Characteristics and the fate of intraluminal thrombus of the intracranial and extracranial cerebral arteries in acute ischemic stroke patients

BACKGROUND: The characteristics and fate of intraluminal thrombus (IT), which may incidentally be detected in acute stroke patients, are not well known and the optimal treatment strategy for IT remains controversial. METHODS: We have identified patients with IT in either the extracranial or intracranial artery and followed up on their clinical courses and imaging findings. We categorized it based on its morphology and investigated clinical outcomes and fate of IT in those patients. RESULTS: Among 495 patients with acute ischemic stroke, 9 (1.9%, 8 men, age range of 61-84 years) were identified with IT. Patients with IT could be categorized into three groups: a filling defect (4) during digital subtraction angiography (DSA), a stenosis-mimic lesion on DSA (3), and a mobile mass on carotid duplex (2). All patients had follow-up vascular imaging studies. Complete or partial resolution of IT was seen in 8 patients. Four patients developed transient or minor ischemic symptoms, which were potentially related to IT. Stenosis-mimic lesions and IT adjacent to atherosclerotic plaques appeared to be associated with unstable clinical courses. CONCLUSIONS: IT can be categorized according to its morphological features. The outcome may depend on the morphology and location of the IT.ope