Table 5.
Neuroimaging studies investigating SCI subjects without NP compared to healthy controls.
| References | Modality | Region of interest(s) | Statistical correction | Main findings |
|---|---|---|---|---|
| Chen et al. (53) | sMRI | Whole brain; S1, M1 and thalamus as region of interests | p < 0.05 cluster-level corrected | SCI-no pain vs. controls: ↓ GMV in L superior parietal lobule ↓ WMV in R temporal lobe, R occipital lobe and R calcarine gyrus |
| Chen et al. (54) | sMRI rsfMRI | Whole brain | sMRI: p < 0.0001 uncorrected, p < 0.05 cluster-level FWE correction; rsfMRI: p < 0.05 k = 30 (Monte Carlo simulation) |
SCI-no pain vs. controls:↓ GMV in L hippocampus, L parahippocampal gyrus, R superior and middle frontal gyrus↔ WMV↓ ALFF in L OFC↓ intranetwork FC in L middle occipital gyrus |
| Jutzeler et al. (55) | sMRI | Whole brain; M1, S1, S2, PMC, insula, thalamus, and ACC as regions of interests | p < 0.05 FWE | SCI-no NP vs. controls:↓ GMV in ACC and M1 |
| Mole et al. (56) | sMRI | Whole brain:M1, S1, thalamus, L posterior cingulate, R insula as regions of interests |
p < 0.001 uncorrected; p < 0.05 FWE correction |
SCI-no NP vs. controls: ↑ GMV in bilateral S1 and L lateral cuneus ↓ WMV of bilateral pyramids and posterior corona radiata |
| Gustin et al. (58) | DTI | Whole brain |
p < 0.005 uncorrected, k = 20 |
SCI-no NP vs. controls: ↓ FA of PPC-to-midbrain fibers ↓ MD of anterior insula, PPC and dorsolateral PFC, nucleus accumbens, ventroposterior thalamus and PMC |
| Gustin et al. (61) | MRS | Thalamus | Independent t tests p < 0.05 |
SCI-no NP vs. controls: No significance |
| Widerström-Noga et al. (62) | MRS | ACC | Independent t tests p < 0.05 |
SCI-no NP vs. controls: No significance |
| Stanwell et al. (63) | MRS | Thalamus, PFC, and ACC | Wavelet-based significant testing p < 0.05 |
SCI-no NP vs. controls: n/a |
| Pattany et al. (64) | MRS | Thalamus | Post hoc t tests p < 0.05 |
SCI-no NP vs. controls:↔ NAA↑ NAA/Ins↓ Ins |
Results of studies investigating differences between SCI-no NP subjects and healthy controls unless stated otherwise. Study order is based on neuroimaging modality as reported in Table 1, starting with structural, DTI, rsfMRI, then MRS.
ACC, anterior cingulate cortex; ALFF, amplitude of low-frequency fluctuations; DTI, diffusion tensor imaging; FA, fractional anisotropy; FWE, family-wise error; GMV, gray matter volume; Ins, myo-inositol; k, minimum cluster size; L, left; M1, motor cortex; MD, mean diffusivity; mFG, medial frontal gyrus; MRS, magnetic resonance spectroscopy; NAA, N-acetyl aspartate; PFC, prefrontal cortex; PMC, premotor cortex; PPC, posterior parietal cortex; R, right; rsfMRI, resting-state fMRI; S1, somatosensory cortex 1; S2, somatosensory cortex 2; SCI, spinal cord injury; sMRI, structural MRI; NP, neuropathic pain; SCI NP, SCI subjects with NP; SCI no NP, SCI subjects without NP; WMV, white matter volume.
↔ No significant changes; ↑ significant increase; ↓ significant decrease.