Significance of ultrasound evaluation of carotid atherosclerotic plaque for diagnosing ischemic cerebrovascular disease*

Abstract

Background Carotid artery is the main source for craniocerebral blood supply. Its intimal plaque formation and arterial stenosis degree both are the risk factors for ischemic cerebrovascular disease. Therefore, the close relationship of carotid atherosclerotic plaque and ischemic cerebrovascular disease, and ultrasound evaluation of carotid atherosclerotic plaque have become the hot spot in studying ischemic cerebrovascular disease. Objective This study was to detect the degree of carotid atherosclerosis of ischemic cerebrovascular disease patients by ultrasonography, and to analyze the situation of carotid atherosclerosis and its relationship with clinic. Design Clinical randomized concurrent control experiment. Setting Lintong Convalescent Hospital of Lanzhou Military Area Command of Chinese PLA. Participants Totally 60 outpatients and inpatients with ischemic cerebrovascular disease, 42 males and 18 females, admitted to Lintong Convalescent Hospital of Lanzhou Military Area Command of Chinese PLA between January 2006 and December 2006 were involved in the patient group. They met the diagnosis criteria of ischemic cerebrovascular disease constituted by the 4 th Cerebrovascular Disease Conference in 1996, and were confirmed to suffer from ischemic cerebrovascular disease by skull CT and MRI. Another 20 subjects who received healthy examination concurrently in the same hospital, 12 males and 8 females, were involved in the control group. Informed consents of detected items were obtained from involved subjects. Methods The plaque thickness of mid portion, distal end and crotch of common carotid artery (CCA), internal carotid artery (ICA), external carotid artery (ECA) and vertebral artery (VA) of involved subjects, who received health examination was separately detected with color Doppler ultrasonograph (HDI-5000). Then, total integral of plaque was calculated. The intima-media thickness (IMT) was measured with two-dimensional ultrasonography. The inner diameter stenosis degree of subjects who had plaque was measured. Blood flow parameters were recorded, and stenosis degree and plaque area were calculated. Blood flow volume of bilateral carotid artery and VA was separately measured with ultrasound equipment software, and brain blood flow volume was calculated. Main outcome measures Atherosclerotic degree and blood flow volume of patients of two groups. Results Sixty patients with ischemic cerebrovascular disease and twenty subjects who received health examination participated in the final analysis. ▪ The IMT thickness, total plaque score, and total plaque area of patient group was significantly superior to that of control group, respectively( t=5.216–10.158, P < 0.05). ▪ There were significant differences in the stenosis degree of CCA, ICA and VA between patient group and control group ( t=6.720–12.816, P < 0.05). ▪ The blood flow volume of CCA, ICA, VA and brain of patient group was significantly lower than that of control group, respectively ( t=2.872–10.860, P < 0.05). Conclusion Ischemic cerebrovascular disease patients have different degrees of changes in atherosclerosis and arterial blood flow.