title: Magnetic resonance imaging of the upper abdomen using a free-breathing T2-weighted turbo spin echo sequence with navigator triggered prospective acquisition correction.
abstract: OBJECTIVE
  To evaluate a free-breathing navigator triggered T2-weighted turbo spin-echo sequence with prospective acquisition correction (T2w-PACE-TSE) for MRI of the upper abdomen in comparison to a conventional T2-weighted TSE (T2w-CTSE), a single-shot TSE (T2w-HASTE), and a T1-weighted gradient-echo sequence (T1w-FLASH).
  
  
  METHODS
  A total of 40 consecutive patients were examined at 1.5 T using free-breathing T2w-PACE-TSE, free-breathing T2w-CTSE, and breath-hold T2w-HASTE and T1w-FLASH acquisition. Images were evaluated qualitatively by three radiologists regarding motion artifacts, liver-spleen contrast, depiction of intrahepatic vessels, the pancreas and the adrenal glands, and overall image quality on a four-point scale. Quantitative analysis of the liver-spleen contrast was performed.
  
  
  RESULTS
  Depiction and sharpness of intrahepatic vessels were rated significantly better (P < 0.01) using T2w-PACE-TSE compared to T2w-CTSE and T2w-HASTE sequences. Significantly higher contrast values were measured for T2w-PACE-TSE images compared to T2w-CTSE, T2w-HASTE, and T1w-FLASH images (P < 0.01). Mean examination time of the T2w-PACE-TSE was 7.91 minutes, acquisition time of the T2w-CTSE sequence was 4.52 minutes.
  
  
  CONCLUSIONS
  Prospective acquisition correction is an efficient method for reducing respiratory movement artifacts in T2w-TSE imaging of the upper abdomen. Compared to T2w-CTSE and T2w-HASTE sequences recognition of anatomical details and contrast can be significantly improved.
authors.affiliation: Department of Radiology, Charité-Universitary Medicine Berlin, Campus Charité Mitte, Humboldt-University of Berlin, Berlin, Germany. christian.klessen@charite.de
authors.forename: Christian
authors.initials: C
authors.lastname: Klessen
authors.forename: Patrick
authors.initials: P
authors.lastname: Asbach
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Kroencke
authors.forename: Thomas
authors.initials: T
authors.lastname: Fischer
authors.forename: Carsten
authors.initials: C
authors.lastname: Warmuth
authors.forename: Alto
authors.initials: A
authors.lastname: Stemmer
authors.forename: Bernd
authors.initials: B
authors.lastname: Hamm
authors.forename: Matthias
authors.initials: M
authors.lastname: Taupitz
mesh_terms: D000005:Abdomen / Q000473:pathology*; D000328:Adult; D016477:Artifacts; D004066:Digestive System Diseases / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008107:Liver Diseases; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012119:Respiration; D018709:Statistics, Nonparametric