Jing Yuan1, Pengyu Yan2, Greta S.P. Mok2, Yi-Xiang Wang1, Anil T. Ahuja1, James F. Griffith1
1Department of Imaging and Interventional Radiology, Chinese University of Hong Kong, Shatin, NT, Hong Kong; 2Department of Electrical and Electronics Engineering,, University of Macau, Macau, NA, Macau
T1rho relaxation has potentials for quantitative evaluation of intervertebral disc degeneration. T1rho mapping is traditionally performed using least-squares (LS) fitting but LS method is a biased estimator in the presence of Rician-distributed noise for MR magnitude images. This study investigates the use of maximum likelihood (ML) estimation for lumbar disc T1rho mapping at 3T through Monte-Carlo simulation and in vivo scan. Results show that ML obtains less biased and more accurate estimation of lumbar disc T1rho compared to LS, particularly at low signal-to-noise ratios. ML benefits high spatial resolution spine T1rho imaging without compromising the accuracy of T1rho estimation.