We investigated the clinical significance of carotid bruits in 238 patients with ischemic stroke using carotid ultrasonography. We recognized carotid bruits in 4 1 (17.2%)of the patients on auscultation of the neck. Patients with carotid bruits tended to have risk factors of ischemic heart disease and to be male. and symptomatic cerebral infarction with significantly more frequent than in patients without carotid bruits (p<0.05). Internal carotid artery stenosis (area of stenosis ≥50%), turbulence flow, and peak systolic velocity ≥150 cm/sec were observed significantly more frequently in patients with carotid bruits (p<0.05). Age, diabetes mellitus, hypertension. cigarette smoking. and dyslipidemia were not proved to have a significant correlation with the presence of carotid bruits. These findings indicate that carotid bruits are associated with advanced atherosclerosis in many organs.
In recent years. the use of carotid ultrasound for screening of cerebrovascular disease has increased at our hospital. We have formulated criteria based on plaque score (PS) and evaluated their validity. Our PS criteria are : PS 1. 0 to <5.0 (normal or mild atherosclerosis), for which ultrasound within one year is recommended, PS 5.0 to <10.0 (moderate atherosclerosis), for which MRI is recommended. and PS >10.0 (severe atherosclerosis), for which MRI and SPECT are recommended. We enrolled 1167 patients with lifestyle-related disease who underwent carotid ultrasound examination between May 2005 and August 2006. We evaluated the proportions of patients in each group who underwent MRI, and the frequency of abnormal MRI findings in each group. The proportions of patients who underwent MRl were 18.2% in the PS normal group. 32.5% in the PS mild group. 69.3% in the PS moderate group. and 87.1% in the PS severe group. The frequency of asymptomatic cerebral infarction evident on MRI was 15.0% in the PS normal group, 26.2% in the PS mild group, 39.3% in the PS moderate group. and 49.5% in the PS severe group. The corresponding frequencies of intracranial arterial stenosis were 25.0%, 22.4%, 42.3% and 62.4%, respectively. PS is a useful index for screening of cerebrovascular disease in patients with lifestyle-related disease.
We investigated endothelial function in 2 1 patients with ischemic stroke (mean age 63 years ; 5 with athero-thrombotic stroke, 14 with lacunar stroke. 2 with cardioembolic stroke)and 20 healthy control subjects (mean age 32 years)using the flow-mediated dilatation (FMD) method. To create a flow stimulus in the brachial artery, a sphygmomanometer cuff was placed above the brachium. The cuff was inflated to at least 30 mmHg above systolic blood pressure for 4.5 min, and then released. Using ultrasonography, we measured the degree of vasodilation of the brachial artery after deflation (%FMD). Maximum %FMD was significantly low in patients with atherothrombotic stroke (5.3±1.5%, p = 0.001)and lacunar stroke (7.6±2.1%, p = 0.01), whereas no significant decrease was observed in patients with cardioembolic stroke (8.4±1.0%, p = 0.26)compared with controls (9.7±2.7%). Among patients with lacunar stroke. %FMD was significantly lower in patients with than in those without diabetes mellitus (DM)(5.3±1.8% vs 8.8±0.6%, p = 0.005). These results indicate that patients with atherothrombotic stroke and lacunar stroke. especially those with DM, have endothelial dysfunction.
Background and purpose : Sonazoid is a new ultrasound contrast agent that is only available for evaluation of liver tumors in Japan. Sonazoid contrast-enhanced ultrasonography (CEUS)enables observation of vessel images and perfusion images continuously. Our aim was to evaluate neovascularization within carotid atherosclerotic plaques using CEUS. Patients and methods : We performed Sonazoid CEUS for 14 patients (16 lesions)with ICA or CCA severe stenoses or occlusions. Nine lesions were symptomatic and the other 7 were asymptomatic. The equipment used was aGE LOGIQ 7 and a 9L probe. CEUS was performed in coded phase inversion mode with MI at 0. 2-O. 3. Sonazoid at 0. 01 ml/kg was injected intravenously as a bolus. From injection up to about 5 min, we observed plaques in the transverse and sagittal views continuously. Results : In 12 of the 16 plaques. some microbubbles were clearly observed moving from the carotid lumen and adventitial vasa vasorum into the plaques. and the accumulated images enabled visualization of neovascularization in the plaques. Many microbubbles were observed in all symptomatic lesions, whereas none were detected in 4 of 7 asymptomatic lesions. Conclusion : CEUS allows noninvasive, effective evaluation of neovascularization within carotid plaques.