Multiparameter estimation using multi-echo spoiled gradient echo with variable flip angles and multicontrast compressed sensing

Purpose: To develop multiparameter mapping including T-1, R-2*, and proton density fat fraction with a single breath-hold to evaluate liver disease and liver function. Methods: A 6-echo spoiled gradient-echo sequence with dual flip angles was used to acquire a 12-set MRI volume data set. To shorten the scan time, undersampling and multicontrast compressed-sensing reconstruction were used. The scan time was 18 seconds. R-2* and proton density fat fraction mapping were achieved by using the iterative least-squares method. T-1 mapping was estimated using driven equilibrium single-pulse observation of T-1. Quantitative values were validated by performing phantom and volunteer studies. Results: Statistical analysis showed that the quantitative values measured using the proposed methods agreed with those measured using conventional methods. T-1 values of water proton measured by the proposed method in phantom and volunteer studies were in good agreement with those by MRS. Conclusion: The results showed that accurate quantitative mapping of T-1, R-2*, and proton density fat fraction with a single breath-hold was achieved using our approach.