Structural neuroimaging studies in POE
Study | Year | Participants (n) | Analysis | Regions evaluated | Key results |
Maier et al 23 | 2000 | 12 POE, 12 EPY-NP, 26 SCZ, 38 HC | Manual tracing, spectroscopy | Hippocampus, amygdala | ↓ Hippocampus/amygdala volume in POE and SCZ, but not in EPY-NP, suggesting common neuropathology |
Briellmann et al 24 | 2000 | 6 PIP, 45 EPY-NP | Manual tracing | Hippocampus | No difference in total hippocampal volumes. PIP group displayed relative anterior hippocampal preservation. |
Marsh et al 25 | 2001 | 9 IIP, 18 EPY-NP, 46 SCZ, 57 HC | Manual tracing and custom automated analysis, T2 relaxometry | Temporal lobe, superior temporal gyrus, hippocampus, ventricles, frontoparietal region | Ventricular enlargement in IIP and SCZ. Temporal and extratemporal cortical grey matter volume deficits in SCZ, IIP and EPY-NP, with greatest abnormalities in IIP group. EPY-NP group had white matter deficits in temporal lobe, and smaller hippocampi. No other differences in hippocampal volumes between groups |
Tebartz van Elst et al 26 | 2002 | 11 IIP, 15 PIP, 24 EPY-NP, 20 HC | Manual tracing, T2 relaxometry | Whole brain, hippocampus, amygdala | POE showed ↓ whole brain volume. No significant difference in hippocampal volumes between groups. Highly significant enlargement of amygdala bilaterally in POE. No significant difference in volumes between IIP and PIP |
Marchetti et al 27 | 2003 | 36 POE, 30 HC | Manual tracing | Hippocampus, amygdala | ↓ Left hippocampus in POE. Hippocampal ratio significantly greater in POE (left laterality effect) |
Rüsch et al 30 | 2004 | 26 IIP and PIP, 24 EPY-NP, 20 HC | VBM (SPM99) | Whole brain | No significant differences in cortical grey matter between POE and TLE |
Flügel et al 28 | 2006 | 20 IIP, 20 EPY-NP, 23 HC | VBM (SPM2), MTR | Whole brain, hippocampus | ↓ MTR signal in left superior and middle temporal gyri in patients with lesion negative IIP. No significant volumetric differences between groups in hippocampus, or other grey and white matter |
Flügel et al 32 | 2006 | 20 IIP, 20 EPY-NP | DTI | Middle frontal gyri, middle temporal gyri | IIP group showed ↓ fractional anisotropy in frontal and temporal regions and ↑ mean diffusivity in bilateral frontal regions. Lower factional anisotropy related to neuropsychological performance |
Sundram et al 33 | 2010 | 5 PIP, 5 IIP, 10 EPY-NP | VBM (SPM5) | Whole brain | ↓ Grey and white matter bilaterally in POE group as compared with EPY-NP group |
DuBois et al 34 | 2011 | 11 PIP, 11 EPY-NP, 11 HC | Cortical thickness (Freesurfer) | Cortex | ↑ Cortical thickness in right lateral prefrontal cortex, rostral anterior cingulate cortex and right middle temporal gyrus in PIP compared with EPY-NP. Thinning in right angular gyrus, and left anterior inferior temporal gyrus in PIP group in comparison to EPY-NP and HC groups |
Gutierrez-Galve et al 36 | 2012 | 22 IIP, 23 EPY-NP, 20 HC | Surface-based morphometry (Freesurfer) | Cortex | ↓ Cortical thickness in inferior frontal gyrus in patients with IIP. IIP group IQ associated with ↓ area (but not thickness) in frontotemporal cortex |
Sone et al 37 | 2016 | 11 POE, 15 EPY-NP, 14 HC | Graph theoretical analysis | Whole brain | ↑ Path length, transitivity, ↓ global efficiency in POE relative to EPY-NP group. ↓ connectivity in contralateral temporal lobe, ipsilateral middle frontal gyrus and bilateral postcentral gyri in POE group |
DTI, diffusion tensor imaging; EPY-NP, epilepsy without psychosis; HC, healthy control; IIP, interictal psychosis; MTR, magnetisation transfer ratio; PIP, postictal psychosis; POE, psychosis of epilepsy; SCZ, schizophrenia; SPM, statistical parametric mapping; TLE, temporal lobe epilepsy; VBM, voxel-based morphometry.