右侧颈动脉易损性斑块破裂形成溃疡，伴随自由漂浮血栓及中度狭窄

In summary, the diagnosis of ultrasound contrast examination is a ruptured vulnerable plaque with ulcer formation in the right carotid artery, accompanied by the formation of a free-floating thrombus, and moderate stenosis at the beginning of the right internal carotid artery.