Comparison of gradient-echo and steady-state free precession for coronary artery magnetic resonance angiography using a gadolinium-based intravascular contrast agent.
OBJECTIVE
Intravascular contrast agents may offer longer imaging times and better vessel visualization over conventional extravascular agents for magnetic resonance coronary angiography. The purpose of this study was to evaluate the effect of intravascular contrast (B-22956/1) on coronary visualization. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared in inversion-recovery (IR)-prepared FLASH (fast low-angle shot) and IR-trueFISP (true fast imaging with steady-state precession) sequences before and after contrast.


METHODS
Numeric simulations were performed to compare blood signals in IR-trueFISP and IR-FLASH sequences. Coronary imaging was performed in 15 swine.


RESULTS
Postcontrast CNR was improved 23% with breathhold IR-FLASH and 55% with breathhold IR-trueFISP as compared with precontrast trueFISP. With free-breathing, long TR IR-FLASH provided 131% and 55.8% higher SNR and 132% and 58.7% increased CNR compared with IR-FLASH with shorter TR and IR-trueFISP, respectively.


CONCLUSIONS
Intravascular contrast agents improve CNR and vessel visualization in coronary magnetic resonance angiography with IR-FLASH and IR-trueFISP.
Deshpande
Vibhas S
VS
Siemens Medical Solutions, Los Angeles, California 90095, USA.Vibhas.Deshpande@siemens.com
Cavagna
Friedrich
F
Maggioni
Fabio
F
Schirf
Brian E
BE
Omary
Reed A
RA
Li
Debiao
D
D000818:Animals; D003287:Contrast Media / Q000493:pharmacokinetics*; D017023:Coronary Angiography / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D009942:Organometallic Compounds / Q000493:pharmacokinetics*; D013552:Swine
C440468:B-22956-1; D003287:Contrast Media; D009942:Organometallic Compounds