title: Magnetic resonance cholangiopancreatography using a free-breathing T2-weighted turbo spin-echo sequence with navigator-triggered prospective acquisition correction.
abstract: OBJECTIVE
  The objective of this study was to evaluate the image quality of a respiratory-triggered T2-weighted (T2w) turbo spin-echo (TSE) sequence for magnetic resonance cholangiopancreatography (MRCP) using a new method for respiratory triggering by tracking the motion of the right diaphragm [prospective acquisition correction (PACE) technique].
  
  
  METHODS
  Fifty consecutive patients underwent MRCP imaging applying breath-hold half-Fourier single-shot TSE sequences and the respiratory-triggered T2w TSE sequence. Qualitative evaluation grading the depiction of eight segments of the pancreaticobiliary tree and the frequency of artifacts was performed. Quantitative evaluation included calculation of the relative contrast (RC) between fluid-filled ductal structures and organ parenchyma at four segments.
  
  
  RESULTS
  A significantly higher (P<.01) RC was measured for the respiratory-triggered T2w TSE sequence [maximum intensity projection (MIP)] for all of the four investigated segments (one of four segments for the MIP) of the pancreaticobiliary tree, as well as a significant (P<.01) improvement of visualization of all ductal segments compared with the breath-hold sequences. The frequency of artifacts was significantly lower (P<.01) compared with the breath-hold sequences.
  
  
  CONCLUSIONS
  Respiratory-triggered MRCP using a T2w TSE sequence with PACE significantly improves image quality and may be included into the routine MRCP sequence protocol.
authors.affiliation: Department of Radiology, Charité-Universitaetsmedizin Berlin, Charité Campus Mitte, Humboldt University, Schumannstr. 20/21, Berlin 10098, Germany. patrick.asbach@charite.de
authors.forename: Patrick
authors.initials: P
authors.lastname: Asbach
authors.forename: Christian
authors.initials: C
authors.lastname: Klessen
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Kroencke
authors.forename: Claudia
authors.initials: C
authors.lastname: Kluner
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: D000328:Adult; D000368:Aged; D016477:Artifacts; D049448:Cholangiopancreatography, Magnetic Resonance / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012119:Respiration; D018709:Statistics, Nonparametric