title: Investigating the quantitative fidelity of prospectively undersampled chemical shift imaging in muscular dystrophy with compressed sensing and parallel imaging reconstruction.
abstract: OBJECTIVE
  Fat fraction measurement in muscular dystrophy has an important role to play in future therapy trials. Undersampled data acquisition reconstructed by combined compressed sensing and parallel imaging (CS-PI) can potentially reduce trial cost and improve compliance. These benefits are only gained from prospectively undersampled acquisitions.
  
  
  METHODS
  Eight patients with Becker muscular dystrophy were recruited and prospectively undersampled data at ratios of 3.65×, 4.94×, and 6.42× were acquired in addition to fully sampled data: equivalent coherent undersamplings were acquired for reconstruction with parallel imaging alone (PI). Fat fraction maps and maps of total signal were created using a combined compressed sensing/parallel imaging (CS-PI) reconstruction.
  
  
  RESULTS
  The CS-PI reconstructions are of sufficient quality to allow muscle delineation at 3.65× and 4.94× undersampling but some muscles were obscured at 6.42×. When plotted against the fat fractions derived from fully sampled data, non-significant bias and 95% limits of agreement of 1.58%, 2.17% and 2.41% were found for the three CS-PI reconstructions, while a 3.36× PI reconstruction yields 2.78%, 1.8 times worse than the equivalent CS-PI reconstruction.
  
  
  CONCLUSIONS
  Prospective undersampling and CS-PI reconstruction of muscle fat fraction mapping can be used to accelerate muscle fat fraction measurement in muscular dystrophy.
authors.affiliation: Newcastle Magnetic Resonance Centre, Institute for Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Kieren G
authors.initials: KG
authors.lastname: Hollingsworth
authors.forename: David M
authors.initials: DM
authors.lastname: Higgins
authors.forename: Michelle
authors.initials: M
authors.lastname: McCallum
authors.forename: Louise
authors.initials: L
authors.lastname: Ward
authors.forename: Anna
authors.initials: A
authors.lastname: Coombs
authors.forename: Volker
authors.initials: V
authors.lastname: Straub
mesh_terms: D000273:Adipose Tissue / Q000473:pathology*; D000328:Adult; D000465:Algorithms; D016477:Artifacts; D044962:Data Compression / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology*; D009136:Muscular Dystrophies / Q000473:pathology*; D015203:Reproducibility of Results; D018401:Sample Size; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D055815:Young Adult
keywords: BMD; MRI; biomarker; compressed sensing; muscular dystrophy