Assessment of hepatic perfusion in pigs by pharmacokinetic analysis of dynamic MR images.
The purpose of this study was to evaluate a new method based on magnetic resonance imaging for the characterization of hepatic perfusion. In nine pigs dynamic MRI was performed before and after partial occlusion of the portal vein. The pharmacokinetic analysis of the contrast enhancement resulted in a set of parameters (amplitude, A; perfusion rate, kp; elimination rate, kappa(e1); lag time, t(lag)) of which kp was expected to correlate with hepatic perfusion. Reference measurements were done with ultrasound flow-meters and with a thermal diffusion probe (TDP). MR perfusion rate kp significantly dropped under partial portal vein occlusion from an average of 11.3 to 4.9 min(-1) (P < 0.001), while the difference in amplitude A was not significant. The correlation between kp and the TDP measurement was r = 0.89 (P < 0.001). Pharmacokinetic analysis of MRI contrast enhancement provides a non-invasive assessment of hepatic perfusion.
Scharf
J
J
Department of Radiology, University of Heidelberg Medical School, Germany. i33@ix.urz.uni-heidelberg.de
Zapletal
C
C
Hess
T
T
Hoffmann
U
U
Mehrabi
A
A
Mihm
D
D
Hoffmann
V
V
Brix
G
G
Kraus
T
T
Richter
G M
GM
Klar
E
E
D000818:Animals; D003287:Contrast Media / Q000493:pharmacokinetics*; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D006499:Hepatic Artery / Q000033:anatomy & histology; D008099:Liver / Q000033:anatomy & histology* / Q000378:metabolism*; D008102:Liver Circulation; D018810:Magnetic Resonance Angiography / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D011169:Portal Vein / Q000033:anatomy & histology; D018709:Statistics, Nonparametric; D013552:Swine
D003287:Contrast Media; D019786:Gadolinium DTPA