title: Operator-independent isotropic three-dimensional magnetic resonance imaging for morphology in congenital heart disease: a validation study.
abstract: BACKGROUND
  Operator-independent isotropic 3D MRI may greatly simplify the assessment of complex morphology in congenital heart disease. We sought to evaluate the reliability of this new approach.
  
  
  RESULTS
  In 31 adolescent and adult patients (age, 6 to 42 years; median, 16 years) with congenital heart disease, cardiac morphology was determined with free-breathing (navigator-gated), isotropic, 3D steady-state free-precession (3D SSFP) MRI and independently evaluated by 2 observers. Cardiac diagnoses and multiple distance measurements were compared with conventional MR reference sequences (ie, spin-echo, cine gradient-echo, contrast-enhanced MR angiography) and with echocardiography/cine cardioangiography or surgery. Of the 31 patients, 24 had native congenital heart defects or residual defects after repair that warranted immediate treatment. None of these defects was missed by 3D SSFP. Novel diagnostic issues were discovered in 4 of 31 patients (coronary anomalies, n=3; left juxtaposition of the right atrial appendage in double-outlet right ventricle and transposition of the great arteries, 1). For sizes of valves and vessels, we found minor mean differences of -1.1 to 1.6 mm, with SD ranging from 1.2 to 2.9 mm, demonstrating overall good agreement with standard MRI (Bland-Altman analysis). Interobserver variability of 3D SSFP distance measures was low; mean differences ranged from -1.5 to 1.0 mm, and SD ranged from 0.8 to 2.5 mm. Scatter was lower for extracardiac than intracardiac measures.
  
  
  CONCLUSIONS
  In adolescents and adults, isotropic 3D SSFP MRI allows reliable assessment of complex cardiac morphology. Distance measurements are accurate and reproducible. Thus, a single operator-independent acquisition may substitute for conventional 2D MRI sequences to accelerate and simplify MR scanning in congenital heart disease.
authors.affiliation: Department of Cardiothoracic Surgery, Institute of Experimental Clinical Research, Skejby Hospital, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Thomas Sangild
authors.initials: TS
authors.lastname: Sørensen
authors.forename: Hermann
authors.initials: H
authors.lastname: Körperich
authors.forename: Gerald F
authors.initials: GF
authors.lastname: Greil
authors.forename: Joachim
authors.initials: J
authors.lastname: Eichhorn
authors.forename: Peter
authors.initials: P
authors.lastname: Barth
authors.forename: Hans
authors.initials: H
authors.lastname: Meyer
authors.forename: Erik Morre
authors.initials: EM
authors.lastname: Pedersen
authors.forename: Philipp
authors.initials: P
authors.lastname: Beerbaum
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009206:Myocardium / Q000473:pathology*; D015588:Observer Variation; D015203:Reproducibility of Results