Multi-exponential T2 Myelin Water Imaging in Ex-Vivo Rodent Brain at 7T and 15.2T

Abstract

To apply MWI techniques to excised, fixed rodent brains, multi-exponential T2 (MET2) data were acquired at high (7T) and ultra-high (15.2T) fields with and without tissue doping with Gadolinium to increase SNR efficiency. From relaxivity measurements, optimal scan parameters are found based on the minimal Cramér-Rao lower bounds (CRLB) of variance of myelin water fraction (MWF). Subsequently acquired MET2 data were analyzed to obtain myelin water fraction (MWF) maps with and without contrast agent at each field strength with various techniques, displaying the potential for MWI in rodent brain in the study of myelin content across whole brain.