Contrast-enhanced ultrasound reveals free-floating thrombus in carotid artery: The cause of stroke is surprisingly plaque rupture.

Background: Acute stroke poses a serious threat to people's health. The occurrence of a thrombus following the rupture of vulnerable plaques in the carotid artery is a significant contributor to the development of stroke. In previous case reports, it has been challenging to visualize tiny ulcerations within carotid artery plaques using computed tomography angiography (CTA) and digital subtraction angiography (DSA), even when the rupture of the plaque leads to the formation of a free-floating thrombus (FFT). However, in this particular case, contrast-enhanced ultrasound (CEUS) was able to overcome this limitation and provide a more precise assessment, confirming that the FFT formation was indeed a result of plaque rupture rather than any other potential causes. Cases that utilize CEUS to visualize the formation of ulcers and FFT resulting from plaque rupture are even more rare. As such, we present this case to shed light on this infrequent phenomenon.

Case Summary: In this case study, we present a 65-year-old male patient who was admitted to the hospital due to headache and abnormal mental behavior for one day. During the routine cervical artery ultrasound examination upon admission, we detected the presence of plaque in the right internal carotid artery of the patient, resulting in luminal stenosis. Additionally, we observed suspected hypoechoic material at the distal end of the plaque. After undergoing CEUS examination, it was definitively determined that an ulcer had formed and a FFT had developed due to the rupture of carotid artery plaque. Subsequent CTA and DSA examinations further confirmed the presence of the FFT. The magnetic resonance imaging (MRI) reveals an acute lacunar infarction in the head of the right caput nuclei caudate, which strengthens the potential link between the patient's neurological and psychiatric symptoms observed during admission. The patient received prompt antiplatelet therapy and underwent cervical artery stenting surgery with the assistance of a distal embolic protection device. Following the procedure, the patient was discharged on the fourth day and experienced a complete recovery.

Conclusion: CEUS is a valuable tool for visualizing FFT resulting from the rupture of vulnerable plaques in the carotid artery.