Comparison between intravenous and intraarterial contrast injections for dynamic 3D MRI of liver tumors in the VX2 rabbit model.
OBJECTIVE
To test the hypothesis that catheter-directed intraarterial (IA) contrast agent injection increases tumor enhancement and conspicuity compared to intravenous (IV) injection.


METHODS
Eight VX2 liver tumors were grown in five rabbits. After positioning a catheter in the hepatic artery, we performed 3D inversion recovery GRE MRI after IA and IV gadopentetate-dimeglumine contrast injections at doses of 0.04 and 0.1 mmol/kg, respectively. Peak enhancement (signal-to-noise ratio (SNR)) and conspicuity (contrast-to-noise ratio (CNR)) were measured for each acquisition.


RESULTS
The peak SNR and CNR were 21.7 +/- 5.8 and 17.0 +/- 4.8 (mean +/- SD) after IA injection, and 16.9 +/- 10.2 and 6.2 +/- 2.6 after IV injection. The IA CNR was significantly greater than the IV CNR (P < 0.05), with a >60% increase in CNR for each tumor. For six of the eight tumors the IA SNR was greater than the IV SNR, but statistical significance was not achieved due to the small sample size of the study (P = 0.07).


CONCLUSIONS
We demonstrated the feasibility of using IA injection techniques to improve tumor conspicuity. This strategy could be employed to enhance the detection of small liver tumors or to conserve contrast agent in future MRI-guided transcatheter liver therapies.
Larson
Andrew C
AC
Department of Radiology, Northwestern University, Chicago, Illinois, USA. alarson@radiology.northwestern.edu
Rhee
Thomas K
TK
Deng
Jie
J
Wang
Dingxin
D
Sato
Kent T
KT
Salem
Riad
R
Paunesku
Tatjana
T
Woloschak
Gayle
G
Mulcahy
Mary F
MF
Li
Debiao
D
Omary
Reed A
RA
D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage* / Q000494:pharmacology; D004195:Disease Models, Animal; D019786:Gadolinium DTPA / Q000494:pharmacology*; D007261:Infusions, Intra-Arterial / Q000379:methods*; D007262:Infusions, Intravenous / Q000379:methods*; D008099:Liver / Q000473:pathology; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009368:Neoplasm Transplantation; D011817:Rabbits
D003287:Contrast Media; D019786:Gadolinium DTPA