title: A comparison of the approaches to assess the abdominal aortic stiffness using M-mode ultrasonography, tissue tracking and strain rate imaging.
abstract: BACKGROUND
  Which kind of ultrasound imaging technique is suitable for the assessment of the abdominal aortic stiffness are seldom reported. The purposes of this study were to explore a reliable method to evaluate the abdominal aortic stiffness in patients with hypertension among the following ultrasound imaging techniques: M-mode ultrasonography (M-mode), tissue tracking and strain rate imaging.
  
  
  METHODS
  Fifty patients with hypertension and fifty age and sex-matched healthy volunteers were involved in this study. The displacement (d), the peak strain (ε) and the peak strain rate (s) were obtained from the long-axis images of the abdominal aorta using tissue tracking and strain rate imaging, respectively. The pressure strain elastic modulus (Ep), β stiffness index and distensibility were calculated according to the conventional formulas using M-mode combined with the blood pressure.
  
  
  RESULTS
  Compared to the normal subjects, the difference between systolic diameters and diastolic diameters (∆diameter), the displacement of posterior wall (d-posterior), the difference of the displacement between anterior and posterior wall (∆ displacement), and the distensibility decreased and the Ep and β stiffness index increased in the hypertension patients There were no significant differences between the patients with hypertension and the normal subjects according to the ε, s. Among ∆diameters, d-posterior, ∆displacement, the ε and s, only ∆diameters significantly correlated with the Ep, β stiffness index and the distensibility in hypertension patients.
  
  
  CONCLUSIONS
  Strain rate imaging cannot sensitively discriminate the difference of the abdominal aortic stiffness between patients with hypertension and the normal subjects. M-mode ultrasonography is still a classical method for accessing the aortic elasticity.
authors.affiliation: Department of Ultrasound, Jinling Hospital, Nanjing University School of Medicine, Nanjing City, Jiangsu Province, China, Department of Ultrasound, The Fourth Affiliated Hospital of Nantong University, Jiangsu Province, China.
authors.forename: Xiao-Zhi
authors.initials: XZ
authors.lastname: Zheng
authors.affiliation: Department of Ultrasound, Jinling Hospital, Nanjing University School of Medicine, Nanjing City, Jiangsu Province, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Yang
authors.affiliation: Department of Ultrasound, The Fourth Affiliated Hospital of Nantong University, Jiangsu Province, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D001794:Blood Pressure; D016022:Case-Control Studies; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D059289:Vascular Stiffness; D055815:Young Adult