Table 1. 1H-MRS Methods and Their Performance in Identifying IDH-Mutational Status in Gliomas.
| Method | Authors (Ref) | Subject | Number of Subjects (Number of Voxels)* | Sensitivity (%) | Specificity (%)† | Analysis Software | Cutoff CRLB (%)‡ | Reference Peak | Scanner | Field Strength (T) | Number of Channels | Pulse Sequence | TR/TE (TE1, TE2) (ms) | Scan Time (min) | Voxel Volume (cm3) | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MT | WT | Healthy | |||||||||||||||
| Short TE | Andronesi et al. (15) | Human | 2 | 4 | 4 | NA | NA | LCModel | 20 | Glu + Gln | Siemens | 3.0 | 32 | LASER | 1500/45 | 3.2 | 27.0, 42.8 |
| Choi et al. (17) | Human | 22 | - | 7 | 77 | 100 | LCModel | 19 | Water | Philips | 3.0 | 8 | PRESS | 2000/35 (21, 14) | 4.3 | 8.0 | |
| Pope et al. (14) | Human | 9 | 15 | - | 100 | 73 | LCModel | NA | Water, Cr | Siemens | 3.0 | 12 | PRESS | 2000/30 | 4.3 | 8.0 | |
| Natsumeda et al. (18) | Human | 25 (15) | 27 (18) | - | 100 | 72 | LCModel | 35§ | Water | GE | 3.0 | 8 | PRESS | 1500/30 | 3.2–4.9 | (1.2–2.0)3 | |
| Lazovic et al. (20) | Mouse | 8 | 7 | - | 100 | 100 | LCModel | 20 | Cho | Bruker | 7.0 | 1 | PRESS | 4000/6.9 | 34.1 | 3.0 | |
| Short TE with baseline | Heo et al. (22) | Rat | 7 (7) | 6 (6) | (6) | 100 | 83 | MRUI | 20 | Water | Agilent | 9.4 | 1 | SPECIAL | 4000/2.8 | 25.6 | 9.6 × 10-3 |
| Long TE | Choi et al. (16) | Human | 15 | 15 | - | 100 | 100 | LCModel | 19 | Water | Philips | 3.0 | 8 | PRESS | 2000/97 (32, 65) | 2.1 | 8.0 |
| Choi et al. (17) | Human | 22 | - | 7 | 100 | 100 | LCModel | 19 | Water | Philips | 3.0 | 8 | PRESS | 2000/97 (32, 65) | 4.3 | 8.0 | |
| de la Fuente et al. (19) | Human | 22 | 6 | - | 91 | 100 | LCModel | 30∥ | Water | GE | 3.0 | 8 | PRESS | 2000/97 (26, 71) | 5.5–9.5 | 8.0 | |
| Emir et al. (21) | Human | 10 (10) | 4 (4) | 8 (25) | NA | 93 | LCModel | 30 | Water | Siemens | 7.0 | 32 | Semi-LASER | 5000–6000/110 | 10.7–12.8 | 8.0 | |
| Difference editing | Andronesi et al. (15) | Human | 2 | 4 | 4 | NA | NA | MRUI | 20 | Glu + Gln | Siemens | 3.0 | 32 | MEGA-LASER | 1500/75 | 5.0 | 27.0, 42.8 |
| Choi et al. (16) | Human | NA | NA | NA | 100 | 100 | LCModel | NA | Water | Philips | 3.0 | 8 | MEGA-PRESS | 2000/106 (26, 80) | 13.0 | 8.0 | |
| 2D | Andronesi et al. (15) | Human | 2 | 4 | 4 | NA | NA | Matlab | NA | Glu + Gln | Siemens | 3.0 | 32 | LASER-COSY | 1500/45 | 12.8 | 27.0, 42.8 |
*Number of voxels can be different from number of subjects by excluding data with poor quality or by acquiring more data from different regions of brain of same subject, †Specificity: estimated from IDH wild-type tumor voxels + healthy voxels, ‡Cutoff Cramer-Rao lower bound for successful spectral fitting, §For 2HG concentrations of > 1 mM, ∥For 2HG concentrations of ≥ 1 mM. Cho = choline, Cr = creatine, Gln = glutamine, Glu = glutamate, healthy = healthy brain tissue, IDH = isocitrate dehydrogenase, MT = tissue from IDH-mutated tumor, NA = not available, sensitivity = estimated from IDH-mutated tumor voxels, TE1 = 1st echo time, TE2 = 2nd echo time, TR = repetition time, WT = tissue from IDH wild-type tumor, 1H-MRS = proton magnetic resonance spectroscopy, 2HG = 2-hydroxyglutarate