T2 mapping on low-field MR system based on T2NR

In this paper, considering the characteristics of low SNR on low-field MR systems, we presented an optimized and more effective curve fitting method for quantitative T₂ mapping. Series of T₂-weighted images were acquired using a multi-echo spin echo sequence on a Siemens 0.35T open MR system. Adaptive curve fitting algorithm was performed based on T₂-to-noise-ratio (T₂NR) optimization, which was achieved via optimizing the number of echoes used for curve fitting with the prior estimation of T₂ value. Numerical simulation, phantom measurement and volunteer imaging have all shown that more accurate quantitative T₂ mapping, as well as higher SNR, was obtained by the proposed method in comparison with the previous truncated curve fitting method.