title: Assessment of myocardial deformation in children using Digital Imaging and Communications in Medicine (DICOM) data and vendor independent speckle tracking software.
abstract: BACKGROUND
  Analysis of myocardial deformation from data stored in Digital Imaging and Communications in Medicine format using vendor-independent software may be useful for clinical and research purposes but has not been evaluated in children.
  
  
  METHODS
  Grayscale images were prospectively acquired on Vivid 7 (GE Healthcare) and iE33 (Philips Medical Systems) ultrasound systems in 49 children. Digital Imaging and Communications in Medicine and raw data were analyzed using vendor-independent software (Cardiac Performance Analysis, Tomtec Imaging Systems) and vendor-specific software (EchoPAC and QLAB) and results compared. In addition, vendor-independent software using images at 30 frames/sec were compared with images at the higher acquisition frame rate.
  
  
  RESULTS
  Measurement of short-axis radial and circumferential strain (ε) and apical four-chamber longitudinal ε by vendor-independent software was possible in >92% of the children. Intraobserver and interobserver coefficients of variation for global circumferential and longitudinal ε ranged from 7.1% to 15.3% and for radial ε from 23.9% to 30.2%. Strain values were somewhat higher when using GE images at acquisition frame rates compared with ε values using GE images stored at 30 frames/sec. Strain values obtained by vendor-independent software were comparable with those obtained by vendor-specific software for longitudinal ε and higher for circumferential ε. Radial ε values obtained by vendor-independent software were lower than ε values by EchoPAC and higher than ε values by QLAB.
  
  
  CONCLUSIONS
  Vendor-independent software-derived ε is feasible and potentially valuable for measuring myocardial deformation in research and in multicenter studies using images from different ultrasound systems, especially for longitudinal deformation. However, a systematic bias for circumferential ε and a high variability in radial ε measurements remain concerns.
authors.affiliation: Division of Cardiology, Labatt Family Heart Center, Hospital for Sick Children and University of Toronto, Toronto, Ontario, Canada.
authors.forename: Laurens P
authors.initials: LP
authors.lastname: Koopman
authors.forename: Cameron
authors.initials: C
authors.lastname: Slorach
authors.forename: Cedric
authors.initials: C
authors.lastname: Manlhiot
authors.forename: Brian W
authors.initials: BW
authors.lastname: McCrindle
authors.forename: Edgar T
authors.initials: ET
authors.lastname: Jaeggi
authors.forename: Luc
authors.initials: L
authors.lastname: Mertens
authors.forename: Mark K
authors.initials: MK
authors.lastname: Friedberg
mesh_terms: D000293:Adolescent; D000465:Algorithms; D016880:Anisotropy; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography / Q000379:methods*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006331:Heart Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D011873:Radiology Information Systems; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity