title: Comparison of transcatheter intraarterial perfusion MR imaging and fluorescent microsphere perfusion measurements during transcatheter arterial embolization of rabbit liver tumors.
abstract: OBJECTIVE
  Transcatheter intraarterial perfusion (TRIP) magnetic resonance (MR) imaging is clinically used in the interventional MR imaging setting to verify distribution of injected embolic or chemoembolic material during liver-directed transcatheter therapies and to monitor reductions in perfusion. The accuracy of this technique remains unknown. In the present study, rabbit VX2 liver tumors were used to test the hypothesis that TRIP MR imaging accurately measures changes in tumor perfusion during transcatheter arterial embolization (TAE), with injection of fluorescent microspheres used as the gold-standard technique.
  
  
  METHODS
  Five New Zealand White rabbits were used for this study (two donor rabbits and three with VX2 liver tumors). In three rabbits with implanted VX2 liver tumors, catheters were superselectively placed under digital subtraction angiographic guidance into the left hepatic artery supplying the targeted tumor. Fluorescent microspheres were injected into each rabbit's left ventricle before and after TAE. TRIP MR images were obtained at baseline and after embolizations for all rabbits with intraarterial injections of 2.5% gadopentetate dimeglumine solution. Linear regression was used to compare relative reductions in tumor perfusion between TRIP MR imaging and fluorescent microspheres. Results were considered statistically significant at a P value less than .05.
  
  
  RESULTS
  There was good correlation between TRIP MR imaging and fluorescent microsphere measurements of reduction in tumor perfusion (r = 0.722, P < .012).
  
  
  CONCLUSIONS
  TRIP MR imaging provides accurate semiquantitative measurement of perfusion reduction during TAE in rabbit liver tumors.
authors.affiliation: Department of Radiology, Northwestern University, 448 E Ontario St, Suite 700, Chicago, Illinois 60611, USA.
authors.forename: Sumeet
authors.initials: S
authors.lastname: Virmani
authors.forename: Dingxin
authors.initials: D
authors.lastname: Wang
authors.forename: Kathleen R
authors.initials: KR
authors.lastname: Harris
authors.forename: Robert K
authors.initials: RK
authors.lastname: Ryu
authors.forename: Kent T
authors.initials: KT
authors.lastname: Sato
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Lewandowski
authors.forename: Albert A
authors.initials: AA
authors.lastname: Nemcek
authors.forename: Barbara
authors.initials: B
authors.lastname: Szolc-Kowalska
authors.forename: Gayle
authors.initials: G
authors.lastname: Woloschak
authors.forename: Riad
authors.initials: R
authors.lastname: Salem
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Larson
authors.forename: Reed A
authors.initials: RA
authors.lastname: Omary
mesh_terms: D015901:Angiography, Digital Subtraction; D000818:Animals; D045744:Cell Line, Tumor; D003287:Contrast Media / Q000008:administration & dosage; D004621:Embolization, Therapeutic; D005456:Fluorescent Dyes / Q000008:administration & dosage*; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006499:Hepatic Artery / Q000000981:diagnostic imaging; D007269:Injections, Intra-Arterial; D016014:Linear Models; D008102:Liver Circulation; D008114:Liver Neoplasms, Experimental / Q000098:blood supply* / Q000473:pathology / Q000628:therapy*; D018810:Magnetic Resonance Angiography; D008863:Microspheres; D011817:Rabbits; D015203:Reproducibility of Results
chemical_list: D003287:Contrast Media; D005456:Fluorescent Dyes; D019786:Gadolinium DTPA