title: Improved aortic stiffness assessment in the elderly using a one-dimensional fluid displacement MR method.
abstract: OBJECTIVE
  To assess the in vitro accuracy of two rapid projective MR wave velocity measurement sequences, and their relative performance for assessing aortic stiffness in adults of all ages.
  
  
  METHODS
  In vitro testing was performed using latex tube phantoms with precisely-known flow wave velocities, both in the presence and absence of simulated static tissue. A total of 104 adults representing a large age range (21-83 years) underwent aortic wave velocity (AWV) measurements using multiple trials of each method in a single MR session. The relative agreement between the two AWV results in each tertile of subject age and the coefficient of variation of the AWV data were assessed.
  
  
  RESULTS
  In vitro wave velocities did not differ significantly from the known values for either MR method, with or without simulated static tissue. In vivo, the mean AWVs for the young and middle-aged cohorts did not differ significantly between the two MR methods. However, in the elderly group, the two methods did not agree, and one sequence was found to be superior in this age cohort.
  
  
  CONCLUSIONS
  In elderly individuals, a one-dimensional MR method for evaluating aortic stiffness based on aortic blood displacement yields a smaller coefficient of variation and superior overall performance than a similar method based on aortic blood velocity. The two methods perform equivalently in young and middle-aged subjects.
authors.affiliation: Department of Radiology, Virginia Commonwealth University, Richmond, Virginia 23298-0072, USA. kakraft@vcu.edu
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Kraft
authors.forename: Ding-Yu
authors.initials: DY
authors.lastname: Fei
authors.forename: Xianzhi
authors.initials: X
authors.lastname: Shao
authors.forename: Yung-Yeh
authors.initials: YY
authors.lastname: Chang
authors.forename: Ross
authors.initials: R
authors.lastname: Arena
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D001011:Aorta / Q000473:pathology*; D001018:Aortic Diseases / Q000175:diagnosis*; D015331:Cohort Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D019047:Phantoms, Imaging; D012044:Regression Analysis