Delayed Progression of Edema Formation Around a Hematoma Expressing High Levels of VEGF and MMP-9 in a Patient With Traumatic Brain Injury: Case Report

The mechanisms accounting for the development of tissue damage following traumatic brain injury (TBI) have been studied for several decades. A variety of mediators, such as vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9), which play a crucial role in edema formation after TBI, have been identified. We experienced a case of brain edema that progressed continuously at least until 13 days after head injury. The brain edema occurred around the hemorrhage from an intracerebral contusion. The evacuated hematoma was investigated based on the inference that the unexpected expansion of edema was induced by the mediators within the hematoma itself. A 64-year-old woman was admitted to our hospital following a traffic injury. Left brain contusion was revealed by head computed tomography (CT) on admission. Three hours later, formation of an intracerebral hematoma became evident. Serial CT examination revealed that brain edema had developed progressively till 13 days after the injury. A hematoma removal operation was performed on Day 13. The hematoma was centrifuged and the supernatant was analyzed for the expression of VEGF and MMP-9. The values of both (4400 pg/ml and 920 ng/ml, respectively) were extremely high compared with values reported previously in serum and cerebrospinal fluid collected from patients with intracranial infection or injury. This case suggested that the delayed exacerbation of edema following traumatic intracranial hemorrhage was possibly induced by secretory factors such as VEGF and MMP-9 released from within and around the hematoma.