SNR and CNR Performance Comparison in Dixon- Vs. Subtraction-Type Contrast Enhanced MR Angiography

Eric G. Stinson¹, Joshua D. Trzasko¹, Stephen J. Riederer¹

Dixon-based contrast-enhanced MR angiography (CE-MRA) techniques have recently been reported to improve SNR and CNR compared to subtraction-based techniques. Here, a theoretical analysis is performed and compared to numerical and physical phantom results. Dixon CE-MRA shows a signal dependent SNR advantage of a factor of 2 or greater over subtraction CE-MRA and a constant CNR advantage of a factor of about 2 for appropriate TEs. These results indicate that Dixon-type CE-MRA does indeed improve SNR and CNR, in particular at small concentrations of contrast agent, suggesting that Dixon-type CE-MRA may be particularly useful in low contrast dose situations.