Coronary MR angiography: experimental results with a monomer-stabilized blood pool contrast medium.
OBJECTIVE
To evaluate the signal-enhancing characteristics of monomer-coated very small superparamagnetic iron oxide (SPIO) particles used as a blood pool contrast medium for magnetic resonance (MR) angiography in the coronary arteries.


METHODS
The particles used in this study were coated with citrate as the monomer (VSOP-C91). The particles have a total diameter of 7 nm and show the following relaxivities at 0.47 T: T1, 19 L/mmol. sec(-1); T2, 29 L/mmol. sec(-1). Fifteen cardiac MR examinations were performed at 1.5 T in five pigs. Images were acquired from immediately to 35 minutes (equilibrium phase) after intravenous injection of gadopentetate dimeglumine, gadobenate dimeglumine, and the very small SPIO particles (n = 5 for each substance).


RESULTS
Immediately after administration of gadopentetate dimeglumine, gadobenate dimeglumine, and the very small SPIO particles, respectively, increases in the signal-to-noise ratio in blood were 94%, 103%, and 102% and in myocardium were 83%, 83%, and 29% (P <.05, very small SPIO particles versus the low-molecular-weight gadolinium-based compounds). Differences in the blood-to-myocardium contrast-to-noise ratio and visualization of the coronary arteries and their branches were also significant.


CONCLUSIONS
VSOP-C91 significantly improves visualization of the coronary arteries at MR angiography from immediately to 35 minutes after injection.
Taupitz
Matthias
M
Department of Radiology, Institute for Medical Biometry, Charité, Medizinische Fakultät, Humboldt-Universität zu Berlin, Schumannstrasse 20/21, 10098 Berlin, Germany. matthias.taupitz@charite.de
Schnorr
Jörg
J
Wagner
Susanne
S
Abramjuk
Claudia
C
Pilgrimm
Herbert
H
Kivelitz
Dietmar
D
Schink
Tania
T
Hansel
Jörg
J
Laub
Gerhard
G
Hünigen
Hanna
H
Hamm
Bernd
B
D000704:Analysis of Variance; D000818:Animals; D003287:Contrast Media / Q000493:pharmacokinetics*; D017023:Coronary Angiography / Q000379:methods*; D019786:Gadolinium DTPA / Q000493:pharmacokinetics; D007091:Image Processing, Computer-Assisted; D007275:Injections, Intravenous; D007501:Iron / Q000493:pharmacokinetics*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008536:Meglumine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D009942:Organometallic Compounds / Q000493:pharmacokinetics; D010087:Oxides / Q000493:pharmacokinetics*; D010316:Particle Size; D018709:Statistics, Nonparametric; D013552:Swine
D003287:Contrast Media; D009942:Organometallic Compounds; D010087:Oxides; C064572:gadobenic acid; D008536:Meglumine; D007501:Iron; D019786:Gadolinium DTPA