Signal Normalization for MR Spectroscopic Imaging using Brain Tissue Water: Variability & Pathologic Detectability

Mohammad Sabati¹, Varan Govind¹, Andrew a Maudsley¹

Several methods for calibration of brain MR spectroscopic imaging (MRSI) data have been proposed. Referencing to brain tissue water signal has been recommended as this method accounts for RF inhomogeneities and coil loading, which present difficulties when using external reference methods. In this study two methods for deriving the brain tissue water signal are compared: an interleaved MRSI-resolution water reference co-acquired with MRSI data and a high-resolution, quantitative water content mapping. The results show while both normalization methods detected altered metabolites, in agreement with the clinical findings, the water-mapping normalization method provided higher sensitivity for differentiating TBI versus control groups.