Long-Term Cerebellar Consequences of Post-traumatic Brain Injury Assessed by MRI With Diffusion Tensor Imaging

Abstract

BACKGROUND AND OBJECTIVES: Post-traumatic brain injury (TBI) lesions, which combine brain atrophy and white matter injuries, can lead to progressive post-traumatic encephalopathy. However, the specific involvement of the cerebellum, which participates in cognitive, executive, and sensory functions, has been little studied. The aim of this work was to explore the long-term cerebellar consequences of severe TBI. METHODS: In this retrospective study, patients included were hospitalized for a severe TBI and reassessed after discharge with a clinical examination and a MRI with diffusion tensor imaging. Patients were compared with a population of healthy volunteers. For a subgroup of this cohort, we analyzed the evolution of late post-TBI lesions on MRI up to 10 years after TBI. RESULTS: Ninety-seven patients reassessed 5 [3; 6] years after the TBI were included. Volume loss was revealed in the whole cerebellum (P = .01) and especially in the anterior lobe (P < .005) with a decrease in grey matter volume (P = 6.10−3). The mean diffusivity was increased in 4 cerebellar areas which are the right lower, right upper, left lower, and left upper cerebellar peduncles while the fractional anisotropy was decreased in all studied areas (P < 10−3). The longitudinal analysis (n = 17 patients) showed no progression of MRI lesions beyond the acute phase. CONCLUSION: This work shows that even if direct cerebellar damage is rare, long-term post-TBI cerebellar lesions can be observed. Therefore, clinical correlates of cerebellar lesions should be considered more systematically.