Perivascular spaces as a marker of psychological trauma in depression: A 7-Tesla MRI study

Introduction: Emerging evidence in depression suggests that blood–brain barrier (BBB) breakdown and elevated inflammatory cytokines in states of persistent stress or trauma may contribute to the development of symptoms. Signal-to-noise ratio afforded by ultra-high field MRI may aid in the detection of maladaptations of the glymphatic system related to BBB integrity that may not be visualized at lower field strengths. Methods: We investigated the link between glymphatic neuroanatomy via perivascular spaces (PVS) and trauma experience in patients with major depressive disorder (MDD) and in healthy controls using 7-Tesla MRI and a semi-automated segmentation algorithm. Results: After controlling for age and gender, the number of traumatic events was correlated with total PVS volume in MDD patients (r = 0.50, p =.028) and the overall population (r = 0.34, p =.024). The number of traumatic events eliciting horror was positively correlated with total PVS volume in MDD patients (r = 0.50, p =.030) and the overall population (r = 0.32, p =.023). Age correlated positively with PVS count, PVS total volume, and PVS density in all participants (r > 0.35, p <.01). Conclusions: These results suggest a relationship between glymphatic dysfunction related to BBB integrity and psychological trauma, and that glymphatic impairment may play a role in trauma-related symptomatology.