Simultaneous brain susceptibility, T1 and T2 quantification at 7T with phase-cycled balanced steady-state free precession

Motivation: Phase-cycled(PC) balanced steady-state free precession(bSSFP) sequences offer yet-to-be-explored capabilities for quantitative susceptibility mapping(QSM), T1, and T2 mapping, particularly attractive for 7T applications. Goal(s): To determine the potential of PC-bSSFP for simultaneous QSM, T1 and T2 mapping in the brain at 7T. Approach: PC-bSSFP-based off-resonance, tissue phase, T1 and T2 maps are compared with reference maps obtained from ME-GRE and MP2RAGE, in three subjects at 7T. Results: PC-bSSFP-based off-resonance and tissue phase maps agreed with ME-GRE-based references with absolute mean errors of 13.2±3Hz and 8.9±3.7Hz, respectively. PC-bSSFP-based T1 and T2 maps matched the expected brain contrast with high precision. Impact: At 7T, PC-bSSFP enables quantitative measurements of susceptibility, T1, and T2, within one acquisition, while providing high quality weighted images with a clear distinction between different brain structures.