title: Balanced MR cholangiopancreatography with motion-sensitized driven-equilibrium (MSDE) preparation: Feasibility and optimization of imaging parameters.
abstract: OBJECTIVE
  To show the feasibility of motion-sensitized driven-equilibrium-balanced magnetic resonance cholangiopancreatography and to determine the optimal velocity encoding (VENC) value.
  
  
  METHODS
  Sixteen healthy volunteers underwent MRI study using a 1.5-T clinical unit and a 32-channel body array coil. For each volunteer, images were obtained using the following seven respiratory-triggered sequences: (1) balanced magnetic resonance cholangiopancreatography without motion-sensitized driven-equilibrium, and (2)-(7) balanced magnetic resonance cholangiopancreatography with motion-sensitized driven-equilibrium, with VENC=1, 3, 5, 7, 9 and ∞cm/s for the x-, y-, and z-directions, respectively. Quantitative evaluation was obtained by measuring the maximum signal intensity of the common hepatic duct, portal vein, liver tissue including visible peripheral vessels, and liver tissue excluding visible peripheral vessels that were evaluated. We compared the contrast ratios of portal vein/common hepatic duct, liver tissue including visible peripheral vessels/common hepatic duct and liver tissue excluding visible peripheral vessels/common hepatic duct among the five finite sequences (VENC=1, 3, 5, 7, and 9cm/s). Statistical comparisons were performed using the t-test for paired data with the Bonferroni correction.
  
  
  RESULTS
  Suppression of blood vessel signals was achieved with motion-sensitized driven-equilibrium sequences. We found the optimal VENC values to be either 3 or 5cm/s with the best suppression of relative vessel signals to bile ducts. At a lower VENC value (1cm/s), the bile duct signal was reduced, presumably due to minimal biliary flow.
  
  
  CONCLUSIONS
  The feasibility of motion-sensitized driven-equilibrium-balanced magnetic resonance cholangiopancreatography was suggested. The optimal VENC value was considered to be either 3 or 5cm/s. The clinical usefulness of this new magnetic resonance cholangiopancreatography sequence needs to be verified by further studies.
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi Higashi-ku, Fukuoka, 812-8582, Japan. Electronic address: anishie@radiol.med.kyushu-u.ac.jp.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Nishie
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshiura
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Asayama
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Kousei
authors.initials: K
authors.lastname: Ishigami
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kakihara
authors.affiliation: Philips Electronics Japan, 2-13-37 Konan, Minato-ku, Tokyo, 108-8507, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Obara
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D000328:Adult; D001652:Bile Ducts / Q000502:physiology*; D049448:Cholangiopancreatography, Magnetic Resonance / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009038:Motion; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Balanced SSFP; MRCP; MRI; MSDE