Sonodynamic therapy (SDT) is a new treatment for carotid atherosclerotic plaque. The purpose of this study is to evaluate the safety and initial effectiveness of this technique.

Carotid atherosclerotic plaque is an important cause of ischemic stroke. Treatments for patients with carotid plaque include lifestyle changes, medical management(such as control of hyperlipidemia, hypertension, and diabetes) and carotid revascularization(carotid endarterectomy or carotid artery stenting). Studies have suggested that plaque morphology and composition are important determinants of plaque stability, using serial MR imaging of the carotid artery allowed observation of changes in plaque composition. Contrast enhanced ultrasound (CEUS) is a well accepted technique for detection of intraplaque neovascularization(IPN) in carotid atherosclerotic disease. The purpose of this trial is to evaluate the safety and initial effectiveness of SDT. The SDT can induce macrophage elimination and inhibit matrix degradation, which will promote plaque lipid depletion, inflammation level decrease and changes in other plaque tissue components, leading to plaque stabilization and reduction.

Inclusion Criteria:

• Age 18- 80 years
• Carotid artery with 30%~70% stenosis by ultrasound and plaque thickness>2.5mm
• Patients without transient ischemic attack, minor stroke or amaurosis fugax within 6 months
• Patients' LDL-c level below 100 mg/dL(2.6mmol/L), well-controlled blood pressure(systolic BP<140 and diastolic BP<90 under resting conditions) and diabetes(HbA1c<7%)
• Written informed consent

Exclusion Criteria:

• Non-atherosclerotic carotid artery stenosis
• Contraindication to MRI( uses pacemaker, has metallic implants, claustrophobia)
• Acute MI, acute coronary syndrome or stroke within 4 weeks prior to visit
• Severe cerebral artery stenosis, atrial fibrillation or MRI detected thrombosis that would cause stroke
• Previous significant adverse reaction to a statin
• Systemic disorders such as hepatic, renal, hematologic, and malignant disease
• Medical history that might limit the individual's ability to take trial treatments for the duration of the study
• Allergic to DVDMS or sonovue
• Diagnosis of porphyria
• Pregnant women and nursing mothers
• History of bilateral carotid endarterectomy or has immediate plans for carotid endarterectomy
• Patient who is attending other clinical trial