title: Image quality and bile duct volumetry in MR cholangiopancreatography augmented with low-dose morphine.
abstract: OBJECTIVE
  Opioids are applied to augment visualization of the biliary system in MR cholangiopancreatography (MRCP) to take advantage of a side effect, the constriction of the sphincter of Oddi. This prospective study was performed to determine the effect of IV low-dose morphine on image quality and bile duct delineation in MRCP.
  
  
  METHODS
  Fifteen healthy volunteers and 15 consecutive patients underwent MRCP on a 1.5-T MRI scanner. Strongly T2-weighted 3D single-shot fast spin-echo (SSFSE) sequences were acquired before and 10 minutes after IV administration of morphine (0.04 mg/kg of body weight; mean +/- SD, 2.9 +/- 0.5 mg). Maximum intensity projections were reconstructed from the SSFSE sequence data. Image quality was rated by two independent radiologists using a 4-point scale (1 = excellent, 4 = not diagnostic). Delineation of segmental and subsegmental intrahepatic bile duct orders before and after morphine administration was compared. Volumetry of the common bile duct (CBD) was performed using electronic measurements (AngioTux software, ECCET image processing system).
  
  
  RESULTS
  IV morphine did not significantly improve subjective image quality of the extra- and intrahepatic bile ducts (mean image quality score before vs after morphine administration, 2.3 vs 2.0) or delineation of the intrahepatic bile duct orders. The volume of the CBD remained constant after morphine administration (mean CBD volume before vs after morphine administration, 14.1 vs 13.6 mL). Notable side effects of morphine were seen in two young healthy female volunteers.
  
  
  CONCLUSIONS
  IV-administered low-dose morphine seems to have no essential influence on image quality or delineation of the bile duct system in MRCP. Therefore, the general advice to perform morphine-augmented MRCP should be discussed critically.
authors.affiliation: Department of Radiology, University Hospital Düsseldorf, Germany.
authors.forename: Patric
authors.initials: P
authors.lastname: Kröpil
authors.forename: Andreas
authors.initials: A
authors.lastname: Erhardt
authors.forename: Silke
authors.initials: S
authors.lastname: Mehnert
authors.forename: Andreas
authors.initials: A
authors.lastname: Beck
authors.forename: Dieter
authors.initials: D
authors.lastname: Häussinger
authors.forename: Ulrich
authors.initials: U
authors.lastname: Mödder
authors.forename: Dirk
authors.initials: D
authors.lastname: Blondin
mesh_terms: D000328:Adult; D000368:Aged; D001652:Bile Ducts / Q000473:pathology*; D016022:Case-Control Studies; D049448:Cholangiopancreatography, Magnetic Resonance / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage*; D009294:Narcotics / Q000008:administration & dosage*; D011446:Prospective Studies; D018709:Statistics, Nonparametric
chemical_list: D009294:Narcotics; D009020:Morphine