Comparison of two blood pool contrast agents for 0.5-T MR angiography: experimental study in rabbits.
OBJECTIVE
To evaluate two experimental blood pool agents for potential use in equilibrium phase abdominal magnetic resonance (MR) angiography.


METHODS
MR imaging at 0.5 T was performed in 37 rabbits before and after intravenous injection of a gadolinium-based blood pool contrast agent (SH L 643 A), superparamagnetic iron oxide blood pool agent (SH U 555 C), or gadopentetate dimeglumine. T1-weighted fast spoiled gradient-echo images from the renal arteries to below the iliac bifurcation were obtained. The aorta-to-tissue signal difference-to-noise ratio (SDNR) was measured over time.


RESULTS
Both blood pool agents yielded excellent demonstration of the rabbit abdominal aorta. At a dose of 0.1 mmol/kg, both provided a statistically significant increase in aorta-to-tissue SDNR in comparison with that achieved with gadopentetate dimeglumine (200% increase for SH L 643 A, 95% increase for SH U 555 C; P < .05). A 0.1 mmol/kg dose of SH L 643 A provided a 24% increase in SDNR relative to the increase with a 0.37 mmol/kg dose of gadopentetate dimeglumine. Time-dependent enhancement properties of the blood pool agents differed due to differences in elimination method.


CONCLUSIONS
Both blood pool agents were found to be promising contrast agents for 0.5-T MR angiography; however, their clinical applicability warrants further investigation. The gadolinium-based agent had several advantages over the iron oxide compound, including less T2* dephasing, lack of susceptibility artifacts, and fast renal elimination.
Clarke
S E
SE
Robarts Research Institute, Imaging Research Laboratories, London, Ontario, Canada.
Weinmann
H J
HJ
Dai
E
E
Lucas
A R
AR
Rutt
B K
BK
D000005:Abdomen / Q000098:blood supply; D000818:Animals; D001027:Aortography; D003287:Contrast Media / Q000008:administration & dosage / Q000493:pharmacokinetics*; D003911:Dextrans; D052203:Ferrosoferric Oxide; D005682:Gadolinium; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000493:pharmacokinetics; D007501:Iron / Q000493:pharmacokinetics*; D018810:Magnetic Resonance Angiography; D058185:Magnetite Nanoparticles; D008297:Male; D010087:Oxides / Q000493:pharmacokinetics*; D011817:Rabbits; D012680:Sensitivity and Specificity
D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; C402765:gadomer 17; D005682:Gadolinium; D007501:Iron; C065507:ferumoxides; D019786:Gadolinium DTPA; D052203:Ferrosoferric Oxide