Using proton magnetic resonance spectroscopic imaging to study glutamatergic alterations in patients with schizophrenia: A systematic review.

The glutamate hypothesis of schizophrenia posits aberrant glutamatergic activity in patients with schizophrenia. Levels of glutamate and glutamine can be detected and quantified in vivo by proton magnetic resonance spectroscopy. A related technique, proton magnetic resonance spectroscopic imaging ( ¹ H-MRSI), is particularly useful as it simultaneously collects multiple spectra, across multiple voxels, from a single acquisition. The primary aim of this study was to review and discuss the use of ¹ H-MRSI to measure levels of glutamate and glutamine in patients with schizophrenia. Additionally, the advantages and disadvantages of using ¹ H-MRSI to examine schizophrenia pathophysiology are discussed. A literature search was conducted through Ovid. English language studies utilizing ¹ H-MRSI to measure glutamate and glutamine in patients with schizophrenia were identified. Six studies met the inclusion criteria. The included studies provide inconclusive support for glutamatergic elevations within frontal brain regions in patients with schizophrenia. The key benefit of employing ¹ H-MRSI to examine schizophrenia pathophysiology appears to be its broader spatial coverage. Future ¹ H-MRSI studies utilizing large sample sizes and longitudinal study designs are necessitated to further our understanding of glutamatergic alterations in patients with schizophrenia.
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