Single-scan quantitative T2 methods with susceptibility artifact reduction

Two imaging methods, MSSAVE (Multiple echo SubSlice AVEraging imaging), based on sub‐slice averaging and MGESEPI (Multiple echo Gradient‐Echo Slice‐Excitation Profile Imaging), based on over‐sampling in the slice direction, are proposed for single‐scan quantitative T2* evaluation with susceptibility artifact compensation. Their potentials in terms of sensitivity, minimum performance time, susceptibility artifact reduction and T2* quantitation quality, were compared with existing single‐scan methods such as classical FLASH two‐ or three‐dimensional or z‐shimmed methods both in vitro and in vivo in normal rat brain. MGESEPI offered good quality T2* maps nearly free of artifacts but required a long acquisition time. MSSAVE was faster, but at the expense of reduced artifact compensation and the achievable T2* quantitation quality. Copyright © 2006 John Wiley & Sons, Ltd.