title: Detection of subclinical atherosclerosis in asymptomatic subjects using ultrasound radiofrequency-tracking technology.
abstract: OBJECTIVE
  Atherosclerosis is a chronic and systemic disease and its developmental process involves the synergism of multiple risk factors such as hypertension, dyslipidemia, diabetes, obesity and smoking. The diagnosis of subclinical atherosclerosis is essential for strategic guidance towards suitable treatments and efficient prevention against acute cardiovascular events. This study employed ultrasound radiofrequency (RF) tracking technology to characterize human carotid arteries in vivo in terms of intima-media thickness (IMT) and artery stiffness, and evaluated the statistical correlation between carotid IMT and stiffness, and the number of risk factors for atherosclerosis.
  
  
  METHODS
  A total of 160 asymptomatic subjects were enrolled. Ultrasound RF-tracking technology was employed to acquire carotid IMT and stiffness parameters: maximum IMT ((MAX)IMT), RF Quality IMT ((RF)QIMT), distensibility coefficient (DC), compliance coefficient (CC), αindex, β index and local pulse wave velocity (PWVβ). The subjects were categorized in four groups in terms of the number of risk factors: 'zero', 'single', 'double', and 'multiple', and statistical analyses of carotid IMT and stiffness parameters were performed between these different groups.
  
  
  RESULTS
  The subjects (n = 145) with (MAX)IMT smaller than 1.0 mm matched the IMT criteria for non-atherosclerosis and were named as NA-subjects. Spearman's rho correlation analysis of the whole group and the NA-subjects both showed that (MAX)IMT correlated positively with (RF)QIMT, α, β, and PWVβ, and negatively with DC and CC (p<0.01). The analysis of covariance of NA-subjects showed significant differences between subjects with and without risk factors, and also showed significant differences between the 'zero', 'single', 'double', and 'multiple' groups.
  
  
  CONCLUSIONS
  The carotid IMT and stiffness parameters obtained by the ultrasound RF-tracking technology were demonstrated to possess significant statistical correlation with the number of risk factors from 160 subjects, and these anatomical and mechanical parameters may potentially be used together with the IMT criteria to support subclinical atherosclerosis diagnosis.
authors.affiliation: Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Niu
authors.affiliation: Department of Ultrasound, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors.forename: Yanling
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
authors.forename: Long
authors.initials: L
authors.lastname: Meng
authors.affiliation: Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Centre for Biomedical Engineering, and School of Electrical & Electronic Engineering, University of Adelaide, Adelaide, Australia.
authors.forename: Kelvin K L
authors.initials: KK
authors.lastname: Wong
authors.affiliation: Centre for Biomedical Engineering, and School of Electrical & Electronic Engineering, University of Adelaide, Adelaide, Australia.
authors.forename: Derek
authors.initials: D
authors.lastname: Abbott
authors.affiliation: Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
authors.forename: Hairong
authors.initials: H
authors.lastname: Zheng
authors.affiliation: Department of Ultrasound, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors.forename: Rongqin
authors.initials: R
authors.lastname: Zheng
authors.affiliation: Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Qian
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D058070:Asymptomatic Diseases; D050197:Atherosclerosis / Q000000981:diagnostic imaging* / Q000473:pathology; D059168:Carotid Intima-Media Thickness; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D063177:Pulse Wave Analysis; D012307:Risk Factors; D059289:Vascular Stiffness; D055815:Young Adult