title: MR hydrometry to assess exocrine function of the pancreas: initial results of noninvasive quantification of secretion.
abstract: OBJECTIVE
  To evaluate magnetic resonance (MR) hydrometry, a method of quantifying fluid amounts by using MR imaging, for assessing the exocrine function of the pancreas after stimulation with secretin.
  
  
  METHODS
  Images were obtained with a single-shot turbo spin-echo sequence by using a 1.0-T magnet with a quadrature body coil. Image postprocessing and evaluation were performed at an external workstation by using a specially designed histogram algorithm that translates the MR signal intensity of duodenal filling into an actual amount of duodenal fluid. This algorithm was tested in vitro and in vivo. Finally, MR hydrometry results in five patients were correlated with those of the secretin-cerulein test.
  
  
  RESULTS
  The phantom measurements showed a high correlation (r = 0.99) between the actual amount of fluid in the imaging volume and the calculated results. In vivo, the ability of MR hydrometry to enable exact quantification of fluid amounts was demonstrated. In correlating the signal intensity of duodenal filling with the exact amount of additional fluid in the duodenum in volunteers, a coefficient of 0.043 gray tones per pixel per milliliter was calculated. The correlation (r) between secretin-stimulated duodenal fluid output estimated by using tube aspiration and that estimated by using MR hydrometry was 0.946 (P <.05).
  
  
  CONCLUSIONS
  MR hydrometry is a promising noninvasive method of assessing fluid output as a measure of exocrine pancreatic function.
authors.affiliation: Department of Diagnostic Radiology, PU Marburg, University Hospital, Philipps University, Baldingerstrasse, 35033 Marburg, Germany. heverhag@post.med.uni-marburg.de
authors.forename: J T
authors.initials: JT
authors.lastname: Heverhagen
authors.forename: D
authors.initials: D
authors.lastname: Müller
authors.forename: A
authors.initials: A
authors.lastname: Battmann
authors.forename: N
authors.initials: N
authors.lastname: Ishaque
authors.forename: D
authors.initials: D
authors.lastname: Boehm
authors.forename: M
authors.initials: M
authors.lastname: Katschinski
authors.forename: H J
authors.initials: HJ
authors.lastname: Wagner
authors.forename: K J
authors.initials: KJ
authors.lastname: Klose
mesh_terms: D000465:Algorithms; D008279:Magnetic Resonance Imaging / Q000379:methods; D010179:Pancreas / Q000033:anatomy & histology* / Q000378:metabolism*; D019047:Phantoms, Imaging; D012633:Secretin
chemical_list: D012633:Secretin