The Study Of Contrast-enhanced Ultrasound In Evaluating The Intima-media Thickness Of Carotid Artery

Objective: To investigate the value of contrast-enhanced ultrasound in measuringthe intima-media thickness (IMT) of the near-wall and far-wall of carotid artery;toexplore the benefit of contrast-enhanced ultrasound in recognizing the anterior wall ofcarotid artery;to discuss the clinical significance of contrast-enhanced ultrasound indiagnosing atherosclerosis.Methods:The54patients who were underwent two dimensional ultrasound andcontrast-enhanced ultrasound in the period from July of2011to October of2011in thedepartment of internal neurology at the1staffiliated hospital of Dalian MedicalUniversity were included,diagnosed as ischemic cerebrovascular disease,among whomthere were24male patients and30female patients.Acuson S2000color ultrasonicdiagnosing instrument produced by siemens corporation was used with a9L4linear-array probe with a frequency of8-MHz.The contrast agent,SonoVue,with activeingredient of SF6,from Bracco corporation of Italy was diluted by saline with a dose of5ml,then1ml of the mixture was given an bolus injection into cubital vein.The imagesof longitudinal views of the carotid arteries were obtained under two dimensionalultrasound mode and contrast-enhanced ultrasound mode respectively.3measurementsof the largest diameters of carotid arteries were obtained respectively before and aftercontrast-enhanced ultrasound,while the average indexes were needed.At about1~1.5cmproximal to the carotid bifurcation,3measurements of the largest IMT of near-wall andfar-wall of the arteries were obtained respectively before and after contrast-enhancedultrasound,while the average indexes were needed.To define the clarity of intima-mediaof carotid arteries,the patients were divided into three groups,satisfaction group,generalsatisfaction group and dissatisfaction group respectively.Independent-samples T test and Wilcoxon Mann-Whitney test were analysed for the difference of statistical data.Results:1.Between different levels of clarity of intima-media of near-wall of the carotidarteries before and after contrast-enhanced ultrasound,the differences of the clinical datawere statistically significant(P<0.01).It was explained that contrast-enhanced ultrasoundcould improve the levels of clarity of intima-media of near-wall of the carotidarteries.The differences of levels of clarity of intima-media of far-wall of the carotidarteries before and after contrast-enhanced ultrasound were not statisticallysignificant(P>0.05).It was explained that contrast-enhanced ultrasound had similarlevels of clarity of intima-media of near-wall of the carotid arteries as two dimensionalultrasound did.The statistical significance was obtained for the levels of clarity ofintima-media of near-wall and far-wall of the carotid arteries under two dimensionalultrasound mode(P<0.01).It was explained that the levels of clarity of intima-media offar-wall of carotid arteries were higher than those of near-wall of carotid arteries usingtwo dimensional ultrasound.The statistical significance was not obtained in the levels ofclarity of intima-media of near-wall and far-wall of the carotid arteries undercontrast-enhanced ultrasound(P>0.05).It was explained that contrast-enhancedultrasound had similar levels of clarity of intima-media of near-wall and far-wall of thecarotid arteries.2.The diameters of carotid arteries before and after contrast-enhanced ultrasoundhad statistical significance(P<0.05).It was explained that the diameters of carotidarteries under contrast-enhanced ultrasound mode were more than those of carotidarteries under two dimensional ultrasound.3.The differences of IMTs of near-wall of the carotid arteries before and aftercontrast-enhanced ultrasound were statistically significant(P<0.01).It was explained thatcompared to two dimensional ultrasound mode,IMTs of near-wall of the carotid arterieswere more under contrast-enhanced ultrasound mode.The statistical significance wasobtained for IMTs of far-wall of the carotid arteries before and after contrast-enhancedultrasound(P<0.01).It was explained that compared to two dimensional ultrasound,IMTsof far-wall of the carotid arteries were less under contrast-enhanced ultrasoundmode.The differences of IMTs of near-wall and far-wall of the carotid arteries undertwo dimensional ultrasound mode were statistically significant(P<0.01).It wasexplained that IMTs of far-wall of carotid arteries were more than those of near-wall ofcarotid arteries under two dimensional ultrasound mode.The statistical significance was obtained for IMTs of near-wall and far-wall of the carotid arteries undercontrast-enhanced ultrasound mode(P<0.01).It was explained that IMTs of far-wall ofthe carotid arteries were less than those of near-wall of the carotid arteries undercontrast-enhanced ultrasound mode.Conclusions:1.Contrast-enhanced ultrasound could improve markedly the levels of clarity ofintima-media of near-wall of carotid arteries.2.Compared to two-dimensional ultrasound,the diameters of carotid arteries couldbe enlarged under contrast-enhanced ultrasound.3.Compared to two-dimensional ultrasound,IMTs of near-wall of carotid arteriesunder contrast-enhanced ultrasound were increased.4.IMTs of near-wall of carotid arteries under contrast-enhanced ultrasound couldbe used as one of indicators for evaluating the progress of atherosclerosis.