Fast 3D Proton Spectroscopic Imaging of the Human Brain at 3 Tesla By Combining Spectroscopic Missing Pulse SSFP and Echo Planar Spectroscopic Imaging

Introduction: The fast spectroscopic imaging method “spectroscopic missing pulse SSFP” (spMP-SSFP) is one of the candidates for fast 3D proton spectroscopic imaging of the human brain with minimum user interaction [1,2]. However, the minimum total measurement time Tmin is rather long for large spatial 3D matrices, as k-space sampling is only accelerated by using short TR values, typically 150-200 ms. Additionally, if only one accumulation is acquired for a short total measurement time, it is not possible to use phase cycling to suppress artifact signals or to apply k-space weighted averaging to increase the SNRt and improve the spatial response function [3]. In the present study, this disadvantage is eliminated by sampling the echo-like signal in the presence of an oscillating read gradient, i.e. by combining spMP-SSFP with the principle of echo planar spectroscopic imaging (EPSI) [4-6].