Hemodynamics of the Hippocampus and Perilesional Cortex in the Acute and Sub-Acute Phases After Traumatic Brain Injury in Rats

Nick Mark Edward Alexander Hayward¹, Riikka Immonen¹, Asla Pitknen¹, Olli Grhn¹

Traumatic brain injury (TBI) is a leading cause of mortality and morbidity. We assessed the hemodynamics within the hippocampus and perifocal area surrounding the trauma lesion after TBI in rats. Cerebral blood flow (CBF) was quantified using continuous arterial spin labelling. Cerebral blood volume was calculated by measuring MION induced changes in T2 relaxation, all at 4.7 T. Acutely, initial hypoperfusion and CBF recovery was observed in both subregions. Over two subsequent weeks, hippocampal CBF normalized, yet CBF declined gradually in the perifocal cortex. Hemodynamic changes may influence secondary injury cascades as they precede TBI-induced structural changes.