Multiple-echo steady-state (MESS): Simultaneous water-fat separation, $$$T_2$$$, $$$T_2^{'}$$$, and $$$T_2^*$$$ mapping in the knee at 3 tesla

This study proposes an extension of the double-echo steady-state (DESS) sequence to include multiple readouts. This multiple-echo steady-state (MESS) sequence supports quantification of water, fat, $$$T_2$$$, $$$T_2^{'}$$$, and $$$T_2^*$$$ in a single, efficient acquisition. These parameters may provide additional tissue-specific MRI biomarkers for early detection and grading of osteoarthritis (OA), on top of the $$$T_2$$$ quantification of cartilage provided by the DESS sequence. In vivo results show that parameter quantification using MESS corresponds well with quantification on water-selective DESS images.