FIG. 9.

Fat-correction using multipeak fat modeling is necessary for robust R2* mapping in the presence of fat. Images show liver R2* maps on a subject with high liver fat (fat-fraction = 34%), using three different techniques (fat-uncorrected, fat-corrected with single-peak fat and fat-corrected with multipeak fat) and four different TE combinations (3, 4, 5, and 6 echoes). Note the decrease in R2* mapping noise for increasing number of echoes. Fat-uncorrected and single-peak R2* measurements show variability with echo combination, whereas fat-corrected R2* estimates demonstrates excellent robustness to echo combination. Note also the very high apparent R2* in subcutaneous tissue when not accounting for multipeak fat effects.