Traumatic brain injury (TBI) is a significant global health concern and a leading cause of death and disability in children (1). Neuroinflammation, a key response to brain injury activated by central nervous system to repair damage (2–4), can be harmful if prolonged or chronic, contributing to neurodegenerative diseases (5). TBI-induced neuroinflammation impacts the glymphatic system, responsible for clearing metabolic waste and toxic proteins from the brain. Research in mouse models of TBI has shown that this system becomes impaired after TBI, leading to accumulation of waste products (6, 7). This impairment can further promote neuroinflammation and contribute to neurodegeneration (8, 9). The parasagittal dura (PSD) volume is a possible novel magnetic resonance imaging (MRI) based biomarker of neuroinflammation. It is a mesenchymal stromal tissue lining the walls of the superior sagittal sinus and plays crucial role in brain immune surveillance (10–13). Recent studies have linked changes in PSD volume to neurodegenerative conditions like Alzheimer’s disease (14). In this preliminary study, we quantified PSD volume in TBI subjects (N=18, age range: 3-19 y/o, M/F: 9/9) using 3D-T2 Fluid Attenuated Inversion Recovery MRI and an in-house 3DUNet pipeline for tissue segmentation. Mann-Whitney test comparing the medians of percentage of PSD volume relative to intracranial volume in TBI subjects and control subjects (N=18, age range: 4-18 years, M/F: 14/4) revealed statistical significant difference between the two groups (p-value=0.0016). Our initial findings support the notion that PSD volume is increased in patients with neuroinflammation. Additional research is mandatory to confirm these results by increasing patient number and collecting MRI data in chronic TBI.

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