title: Comparison of contrast and noncontrast magnetic resonance angiography for quantitative analysis of thoracic arteries in young patients with congenital heart defects.
abstract: BACKGROUND
  Contrast MRA (C-MRA) is the standard for quantitative analysis of thoracic vessels. We evaluated a noncontrast MRA (NC-MRA) sequence (3-D EKG and navigator-gated SSFP) for quantitative evaluation of the thoracic aorta and branch pulmonary arteries in young patients with congenital heart disease.
  
  
  OBJECTIVE
  To compare contrast and noncontrast magnetic resonance angiography for quantitative analysis of thoracic arteries in young patients with congenital heart defects.
  
  
  METHODS
  Measurements of thoracic aorta and branch pulmonary arteries were obtained from C-MRA and NC-MRA images in 51 patients, ages 2-35 years. Vessel diameters were compared using correlation and Bland-Altman analysis. Interobserver variability was assessed using percent variation.
  
  
  RESULTS
  C-MRA and NC-MRA measurements were highly correlated (r = 0.91-0.98) except for the right pulmonary artery (r = 0.74, 0.78). Agreement of measurements was excellent (mean difference -0.07 to -0.53 mm; mean % difference -1.8 to -4.9%) except for the right pulmonary artery which was less good (mean difference 0.73, -1.38 mm; -3, -10%). Interobserver variability ranged from 5% to 8% for aortic and from 10% to 16% for pulmonary artery measures. The worse agreement and greater variability of the pulmonary artery measures appears due to difficulty standardizing the measurements in patients with abnormal and irregular vessels.
  
  
  CONCLUSIONS
  These data indicate that C-MRA and NC-MRA measures are comparable and could be used interchangeably, avoiding administration of contrast in selected patients.
authors.affiliation: Medical Surgical Department of Pediatric Cardiology, Ospedale Pediatrico Bambino Gesù, Rome, Italy.
authors.forename: Alessia Del
authors.initials: AD
authors.lastname: Pasqua
authors.forename: Silvina
authors.initials: S
authors.lastname: Barcudi
authors.forename: Benedetta
authors.initials: B
authors.lastname: Leonardi
authors.forename: Domenico
authors.initials: D
authors.lastname: Clemente
authors.forename: Mauro
authors.initials: M
authors.lastname: Colajacomo
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Sanders