Alterations in Cerebrospinal Fluid Motion After Mild Traumatic Brain Injury: An Intravoxel Incoherent Motion Magnetic Resonance Imaging Analysis

Purpose : To investigate alterations in cerebrospinal fluid (CSF) motion following mild traumatic brain injury (TBI) using intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) and compare regional CSF dynamics between patients with TBI and healthy controls. Methods : In this prospective observational study, 14 patients with mild TBI and 14 healthy controls underwent IVIM MRI using a 3-Tesla scanner. The f-value, which reflects incoherent microfluidic motion, was calculated in 33 manually defined regions of interest, including the supratentorial, infratentorial, and parenchymal areas. We analyzed group differences in f-values and assessed longitudinal MRI data from three patients with TBI for temporal changes in CSF motion. Results : Compared to healthy controls, patients with TBI showed significantly higher f-values in the infratentorial regions, particularly the left cerebellopontine angle (p=0.0038), and a tendency toward lower f-values in the supratentorial regions, such as the left lateral ventricle and right frontal subarachnoid space. Longitudinal analysis of the three TBI cases revealed increasing f-values in supratentorial regions over time, suggesting recovery from trauma-induced suppression, while infratentorial f-values either decreased or remained stable. One patient who underwent surgical decompression showed increased f-value during the chronic phase. Conclusion : This study provides preliminary evidence that TBI induces region-specific alterations in CSF motion with increased infratentorial and decreased supratentorial activities in the acute phase. Longitudinal changes suggest partial recovery of CSF dynamics, although surgical interventionmay modulate these patterns. IVIM-MRI may serve as a novel tool for detecting posttraumatic CSF motion abnormalities and guide future investigations on their clinical relevance.