Reproducibility of high spatial resolution proton magnetic resonance spectroscopic imaging in the human brains

The application of proton (H-1) magnetic resonance spectroscopic imaging (MRSI) allows for noninvasive, localized analyses of brain biochemistry; however, minimal work has been devoted to the evaluation of H-1 MRSI reproducibility. This study examined the reproducibility of 1H MRSI from five normal subjects on two occasions, separated by 10 days. Reproducibility of the MR signal was evaluated in the context of automated shimming, automated processing, and accurate subject repositioning. Reliability measures for physicochemical indices (choline moieties, creatine, N-acetylaspartate, and myo-inositol) were moderately concordant across repeat studies. Gain variation and repositioning results were excellent. It has been concluded that H-1 MRSI reproducibility is adequate for serial studies of brain metabolism.