title: Free-breathing motion-corrected late-gadolinium-enhancement imaging improves image quality in children.
abstract: BACKGROUND
  The value of late-gadolinium-enhancement (LGE) imaging in the diagnosis and management of pediatric and congenital heart disease is clear; however current acquisition techniques are susceptible to error and artifacts when performed in children because of children's higher heart rates, higher prevalence of sinus arrhythmia, and inability to breath-hold. Commonly used techniques in pediatric LGE imaging include breath-held segmented FLASH (segFLASH) and steady-state free precession-based (segSSFP) imaging. More recently, single-shot SSFP techniques with respiratory motion-corrected averaging have emerged.
  
  
  OBJECTIVE
  This study tested and compared single-shot free-breathing LGE techniques with standard segmented breath-held techniques in children undergoing LGE imaging.
  
  
  METHODS
  Thirty-two consecutive children underwent clinically indicated late-enhancement imaging using intravenous gadobutrol 0.15 mmol/kg. Breath-held segSSFP, breath-held segFLASH, and free-breathing single-shot SSFP LGE sequences were performed in consecutive series in each child. Two blinded reviewers evaluated the quality of the images and rated them on a scale of 1-5 (1 = poor, 5 = superior) based on blood pool-myocardial definition, presence of cardiac motion, presence of respiratory motion artifacts, and image acquisition artifact. We used analysis of variance (ANOVA) to compare groups.
  
  
  RESULTS
  Patients ranged in age from 9 months to 18 years, with a mean +/- standard deviation (SD) of 13.3 +/- 4.8 years. R-R interval at the time of acquisition ranged 366-1,265 milliseconds (ms) (47-164 beats per minute [bpm]), mean +/- SD of 843+/-231 ms (72+/-21 bpm). Mean +/- SD quality ratings for long-axis imaging for segFLASH, segSSFP and single-shot SSFP were 3.1+/-0.9, 3.4+/-0.9 and 4.0+/-0.9, respectively (P < 0.01 by ANOVA). Mean +/- SD quality ratings for short-axis imaging for segFLASH, segSSFP and single-shot SSFP were 3.4+/-1, 3.8+/-0.9 and 4.3+/-0.7, respectively (P < 0.01 by ANOVA).
  
  
  CONCLUSIONS
  Single-shot late-enhancement imaging with motion-corrected averaging is feasible in children, robust at high heart rates and with variable R-R intervals, and can be performed without breath-holding with higher image quality ratings than standard breath-held techniques. Use of free-breathing single-shot motion-corrected technique does not compromise LGE image quality in children who can hold their breath, and it can significantly improve image quality in children who cannot hold their breath or who have significant arrhythmia.
authors.affiliation: Division of Cardiology, Children's National Health System, W3-200, 111 Michigan Ave. NW, Washington, DC, 20010, USA. lolivier@childrensnational.org.|National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA. lolivier@childrensnational.org.
authors.forename: Laura
authors.initials: L
authors.lastname: Olivieri
authors.affiliation: Division of Cardiology, Children's National Health System, W3-200, 111 Michigan Ave. NW, Washington, DC, 20010, USA.
authors.forename: Russell
authors.initials: R
authors.lastname: Cross
authors.affiliation: Division of Cardiology, Children's National Health System, W3-200, 111 Michigan Ave. NW, Washington, DC, 20010, USA.|National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Kendall J
authors.initials: KJ
authors.lastname: O'Brien
authors.affiliation: National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Xue
authors.affiliation: National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Kellman
authors.affiliation: National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Hansen
mesh_terms: D000293:Adolescent; D016477:Artifacts; D055424:Cardiac-Gated Imaging Techniques; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media; D005260:Female; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009942:Organometallic Compounds; D055425:Respiratory-Gated Imaging Techniques
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol
keywords: Children; Free breathing; Heart; Late gadolinium enhancement; Magnetic resonance imaging