title: [Clinical validation of accuracy of anatomical M-mode measurements: effect of harmonic imaging].
abstract: OBJECTIVE
  Recent advances in ultrasound technology allow reconstruction of images from stored radiofrequency information and creating of M-mode echocardiograms along an M-mode cursor of any direction (anatomical M-mode echocardiography).
  
  
  METHODS
  The accuracy of the measurements obtained by anatomical M-mode echocardiography was evaluated by comparing the measurements with those by B-mode echocardiography with or without harmonic imaging in 8 normal subjects and 14 patients with cardiac disorders. Measurements used the left ventricular short-axis image in 4 different directions (0 to 6, 3 to 9, 1 to 7 and 5 to 11 o'clock).
  
  
  RESULTS
  Anatomical M-mode and B-mode measurements showed good linear relationships with correlation coefficients of 0.90 to 0.99 in any of the 4 directions. However, measurements in the lateral direction (3 to 9 o'clock) showed larger errors than those in the other directions (p < 0.05). With the use of harmonic imaging, the errors tended to become smaller, although it did not reach statistical significance.
  
  
  CONCLUSIONS
  Anatomical M-mode echocardiography accurately measures the left ventricular internal diameter in any direction except the lateral direction. Harmonic imaging is useful to decrease the errors.
authors.affiliation: Department of Clinical Physiology, National Cardiovascular Center, Osaka.
authors.forename: K
authors.initials: K
authors.lastname: Katsuki
authors.forename: S
authors.initials: S
authors.lastname: Nakatani
authors.forename: H
authors.initials: H
authors.lastname: Kanzaki
authors.forename: A
authors.initials: A
authors.lastname: Hanatani
authors.forename: N
authors.initials: N
authors.lastname: Tanaka
authors.forename: I
authors.initials: I
authors.lastname: Nakasone
authors.forename: Y
authors.initials: Y
authors.lastname: Masuda
authors.forename: M
authors.initials: M
authors.lastname: Yamagishi
authors.forename: K
authors.initials: K
authors.lastname: Miyatake
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging*; D004452:Echocardiography / Q000379:methods / Q000592:standards*; D005260:Female; D006321:Heart / Q000033:anatomy & histology*; D006801:Humans; D007089:Image Enhancement; D008297:Male; D008875:Middle Aged