Assuntos
Neoplasias Cerebelares , Cisto Epidérmico , Neuroma Acústico , Neoplasias Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/cirurgia , Ângulo Cerebelopontino/diagnóstico por imagem , Ângulo Cerebelopontino/patologia , Cisto Epidérmico/patologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuroma Acústico/patologia , NeuropatologiaRESUMO
PURPOSE: To evaluate whether white matter tracts within the Papez circuit are altered in patients with unilateral hippocampal sclerosis (HS). METHODS: Twenty patients with histologically proven unilateral HS and 20 age-matched controls were studied with a 3T Epilepsy-dedicated MRI protocol including a MPRAGE sequence for hippocampus volumetry and a diffusion tensor imaging (DTI) sequence (61 diffusion-encoding directions, 2×2×2mm3 voxels) for diffusion tensor tractography (DTT). An energy-based global tracking algorithm was used to calculate streamline counts (SC) and fractional anisotropy (FA) of cingulate, fornix, and mammillo-thalamic tracts, respectively. RESULTS: Sclerotic hippocampi were significantly smaller compared to the contralateral side and to age-matched controls. Cingulum SC but not FA were reduced on the hippocampal sclerosis (258+81.0) and contralateral side (271+85.6) compared to age-matched controls (447+138). CONCLUSION: Focusing on white matter tracts of the Papez circuit we showed that in patients with intractable temporal lobe epilepsy unilateral hippocampal sclerosis is associated with a bilateral reduction of cingulum association fibers projecting from the cingulate gyrus to the parahippocampal gyrus.