Background The aim of this study was to investigate the distribution of the regional cerebral blood flow (rCBF) in occupational-related post-traumatic stress disorder (PTSD) subjects and to seek possible correlations between brain perfusion and self-rating scales (SRS) in order to cross-check their diagnostic value and to look for their neural correlates. Method A total of 13 traumatized underground and long-distance train drivers developing (S) and 17 not developing (NS) PTSD who had experienced a ‘person under train’ accident or who had been assaulted at work underwent clinical assessment and 99m Tc-HMPAO SPECT imaging during autobiographical trauma scripts. Statistical parametric mapping was applied to analyse rCBF changes in S as compared with NS and to search for correlations between rCBF and the administered SRS scores, modelling age, months to SPECT and the ratio ‘grey matter/intra-cranial volume’ as nuisance variables. Results Significantly higher activity was observed during trauma script in left posterior and anterior insula, posterior cingulate, inferior parietal lobule, precuneus, caudate and putamen in PTSD subjects as compared with the trauma-exposed control group. Impact of Event Scale and World Health Organisation (10) Well-Being Index scores highly correlated with tracer uptake to a great extent in the same regions in which rCBF differences between S and NS were found. Conclusions These findings support the involvement of insular, cingulate and parietal cortices (as well as the basal ganglia) in the pathogenesis of PTSD and in the processing of related subjective well-being and distress.

Background: Several studies have reported limbic structures volume decrease in Post-Traumatic Stress Disorder (PTSD). However, in PTSD the effect of therapy on brain structures has seldom been investigated. the aim of the study was to evaluate the grey matter (GM) loss in occupational related PTSD and to assess the volumetric differences between patients responding (R) and non-responding (NR) to psychotherapy. Methods: Pre-EMDR MRI data of 21 train drives who did develop PTSD (S) and 22 who did not develop PTSD (NS) after person-under-the-train accidents were compared. Within S further comparisons were made between 10 R to Eye Movement Desensitisation Reprocessing (EMDR) therapy and 5 NR. Data were analysed by optimised voxel-based morphometry as implemented in Statistical Parametric Mapping. Results: As compared to NS, S showed a significant GM volume reduction in precuneus, lingual gyrus, posterior cingulate and parahippocampal cortex. the R>NR comparison highlighted a significant GM reduction in NR in bilateral posterior cingulate, left middle frontal cortex and right parahippocampal, insular and temporal cortices. Conclusions: Comparing two large groups of subjects significant GM volumetric reductions were found in PTSD in posterior limbic structures. NR showed, as compared to R, volume reduction in cortical structures including posterior cingulate and parahippocampal cortex. These latter two structures seem to be the hallmark for both PTSD diagnosis and therapy outcome prediction.