Computer Simulation of the Effects of Contrast Protocols on Aortic Signal Intensity on Magnetic Resonance Angiograms.

BACKGROUND: While iodine-enhanced computed tomography has been studied, detailed information on gadolinium-enhanced magnetic resonance imaging has not been reported.

OBJECTIVE: We evaluated the effects of different gadolinium contrast agent (Gd-CA) factors on the enhancement of aortic magnetic resonance angiography (MRA) using computer simulation.

METHODS: We developed computer-simulation software that combines pharmacokinetic models and tables; it converts the blood concentration of particular Gd-CAs into the signal intensity (SI). We simulated aortic time-intensity curves (TIC) in our MRA study and compared the effect of the Gd-- CA volume, injection rate, and of different Gd-CAs on the TIC.

RESULTS: An increase in the Gd-CA volume from 14.0 to 28.0 ml increased maximal aortic intensity 1.11 times. Changing the injection rate from 1.0 to 2.8 ml/s increased it 1.10 times. The maximal SI of gadoterate-meglumine and gadobutrol was 1.03 and 1.01 times, respectively, that of gadoteridol.

CONCLUSION: In our computer-simulated MRA study, different Gd-CA factors resulted in no significant difference in the maximal aortic SI.