Meeting Banner
Abstract #3979

Fast Whole Brain Quantitative Proton Density Mapping to Normalize 1H MR Spectroscopic Imaging

Angle Lecocq1, Yann Le Fur2, Alexis Amadon3, Alexandre Vignaud3, Monique Bernard4, Maxime Guye1, Jean-Philippe Ranjeva1

1CRMBM, CNRS, Aix-Marseille Univ, MARSEILLE, France; 2CRMBM, CNRS, Aix-Marseille Univ,, MARSEILLE, France; 3LRMN/NeuroSpin/I2BM/CEA, GIF SUR YVETTE, France; 4Aix-Marseille Universit, MARSEILLE, France

In order to normalize CSI water spectrum to obtain signal normalized MR spectroscopic imaging, absolute ρ-maps have to be computed from T1 and T2* maps accounting for B0 and B1 corrections. In this work, we present a very fast method to generate these ρ-maps. A method called XEP recently proposed to obtain fast B1-maps, was combined with a DESPOT1 sequence, an optimized variable flip angle T1 mapping sequence and a conventional T2* mapping sequence. We first validated this method on phantom, and determined proton density maps in three healthy volunteers also explored by CSI technique.

Keywords

absolute achieved acquisition additional aims allowed allows analyzed applied apply approved around audience benefit brain calculation central cerebral channel clinical coil combination combined committee community compatible computation content contents corpus corrected correcting correction covering decreasing definition density dependent derived describing despot determined deviations directly distortions duration durations edges equations equilibrium ethics even exam except excitation explored fast faster fields filter filters frequency generated generation good gradient gray head healthy homogeneity importance intensity intra involved known lasted literature local macroscopic magma mapping maps matrix metabolite minimize minimizing much nevertheless nominal normalization normalize normalized nucleus optimized participate phantom pitfall presence previous previously profiles protocol proton pseudo pulse qualitatively quantitative radio real received receiver reducing required resolution respectively sampling scanned sets skull slices software sometimes sorts spectroscopic spectroscopy spectrum spoil stable steady step structure structures subjects suppressed system target terms thalamus transmitted univ validated variable variations volunteer volunteers water white whole women years yields