title: Estimation of the timing of carotid artery flow using peripheral pulse wave-gated MRI.
abstract: OBJECTIVE
  To investigate the relationship between peripheral pulse wave (PPW)-gating and the carotid systolic pulse wave in a large clinical patient cohort, and to establish a process for correct estimation of delay time from PPW-gating to foot (ie, beginning) or peak times of carotid systolic pulse waves.
  
  
  METHODS
  Subjects comprised 209 patients scanned using 3T magnetic resonance imaging (MRI) for PPW-gated phase contrast images at the common carotid artery. Stepwise multiple regression analysis was conducted for the relationship between foot or peak times and the following factors after excluding correlated factors with coefficients ≥0.5: pulse rate (PR); systolic blood pressure; diastolic blood pressure; height; body weight; body mass index; Brinkman index; diabetes mellitus; hypertension; and hyperlipidemia.
  
  
  RESULTS
  PR showed significant correlation with foot (r = -0.86, P < 0.001) and peak (r = -0.87, P < 0.001) times. The following equations were derived: foot time (msec) = -8.55 × PR + 993.1 and peak time (msec) = -9.21 × PR + 1142.3. No other factors showed significant correlations.
  
  
  CONCLUSIONS
  PR was the only factor showing significant relationships to foot and peak times of carotid artery flow. The derived equations will facilitate various kinds of noncontrast MR acquisition with simple PPW-gating.
authors.affiliation: Department of Radiology, Ichinomiyanishi Hospital, Ichinomiya, Japan. yfushimi@kuhp.kyoto-u.ac.jp
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Fushimi
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Okada
authors.forename: Akira
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Kanagaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Imai
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
mesh_terms: D000465:Algorithms; D001783:Blood Flow Velocity; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods*; D002339:Carotid Arteries / Q000502:physiology*; D059168:Carotid Intima-Media Thickness; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011673:Pulsatile Flow / Q000502:physiology*; D011674:Pulse; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity