Selected studies reporting 1H-MR spectroscopy-detected glutamate and GABA changes in the in vivo brains of patients with neurologic disorders
| Neurologic Disorders | Technique | Region of Interest | MRSI Findings | Reference |
|---|---|---|---|---|
| Epilepsy | ||||
| MTS | Short TE PRESS (Glx); DQF (GABA) | Hippocampus | No change in Glx/Cr and GABA/Cr before and after surgical resection | Simister et al, 200936 |
| MTS (MRI negative) | Short TE PRESS | Hippocampus | Non-significant increase in Glx/Cr | Woermann et al, 199935 |
| Idiopathic generalized epilepsy | Short TE PRESS (Glx); DQF (GABA) | Frontal cortex | Increased Glx/NAA and Glx/ins in patients, no changes in GABA | Simister et al, 200359 |
| Tuberous sclerosis complex | MEGAPRESS | Cortical tubers | Increased GABA in tubers, no change in Glx | Taki et al, 200960 |
| anti-GAD positive epilepsy | MEGAPRESS | Primary sensorimotor cortex | Decreased GABA/NAA, no changes in Glx/NAA | Stagg et al, 201061 |
| Malformations of cortical development | Short TE PRESS (Glx); DQF (GABA) | Cortical malformations | Increased GABA/Cr and Glx/Cr | Simister et al, 200762 |
| Juvenile myoclonic epilepsy | Short TE PRESS | Primary motor cortex/cingulum/ medial prefrontal cortex | Reduced Glx/Cr | Lin et al, 200963 |
| Drugs and epilepsy | ||||
| Levetiracetam | MEGAPRESS | Occipital cortex | Increased GABA/Cr in responders | Doelken, 201064 |
| Vigabatrin | Difference editing | Occipital cortex | Increased GABA/Cr in responders | Mueller et al, 200165; Petroff et al, 199934 |
| Topiramate | Difference editing | Occipital cortex | Acute increase in GABA/Cr | Petroff et al, 200166 |
| Gabapentin | Difference editing | Occipital cortex | Acute increase in GABA/Cr | Petroff et al, 199633 |
| Brain tumors | MRSI | Low-grade oligodendroglioma vs low-grade astrocytoma | Increased Glx in low-grade oligodendrogliomas | Rijpkema et al, 200367 |
| ALS | TE-averaged PRESS | Primary motor cortex and internal capsule | Increased Glx/Cr, increased Glu/Cr | Han and Ma, 201041 |
| Migraine | TE-averaged PRESS | ACC and insula | Low NAAG/Gln in ACC of patients, high NAAG/Gln in insula of patients | Prescot et al, 200968 |
| AD | Macromolecule subtraction | Hippocampus | Decreased Glu/NAA, Glu/Cr; Glu/mI | Rupsingh et al, 201145 |
| 68-ms TE PRESS | Posterior cingulate gyrus | Reduced Glx/Cr | Antuono et al, 200169 | |
| Short TE PRESS | Precuneus, posterior cingulate cortex, parieto-occipital white matter | Decreased Glx/Cr in gray matter only | Hattori et al, 200270 | |
| Drugs and AD | ||||
| Galantamine | Macromolecule subtraction | Hippocampus | Increased Glu | Penner et al, 201048 |
| Memantine | MRSI | Bilateral hippocampi | Decreased Glu/Cr | Glodzik et al, 200871 |
| PD | Short TE PRESS | Posterior cingulate gyrus | Reduced Glu/Cr | Griffith et al, 200849 |
| TE averaged PRESS | Lentiform nucleus | No change in Glu | Kickler et al, 200756 | |
| STEAM | Substantia nigra | Increased GABA/Glu | Oz et al, 200672 |
Note:—MTS indicates mesial temporal sclerosis; MRI, MR imaging; GAD, glutamic acid decarboxylase; PRESS, point-resolved spectroscopic sequence; Glx, glutamine/glutamate; DQF, double-quantum filter; MEGAPRESS, MEGA point-resolved spectroscopy; MRSI, MR spectroscopy imaging; STEAM, short echo time stimulated echo acquisition mode; ACC, anterior cingulate cortex; ins, inositol; Glu, glutamate; Gln, glutamine