Atrophy patterns of gray matter volume and the correlation with the disease duration in the cerebellum and hippocampal subregions in mesial temporal lobe epilepsy.

BACKGROUND

Hippocampal pathology is a hallmark of mesial temporal lobe epilepsy (MTLE), but the involvement of cerebellar structures and their relationship with disease duration remain less defined. This study aimed to map gray matter volume (GMV) changes in hippocampal and cerebellar subregions and examine their associations with disease duration.

METHODS

Sixty MTLE patients (33 left-onset, 27 right-onset) and 13 healthy controls underwent high-resolution structural MRI. GMV was quantified using voxel-based morphometry and SUIT-VBM with subregional segmentation. Correlation analyses examined GMV-duration relationships in the whole cohort and by seizure-onset laterality. Group comparisons were made between short-duration (<10 years) and long-duration (≥10 years) MTLE and controls. Lateralization indices were calculated to assess asymmetry.

RESULTS

Significant negative correlations between disease duration and GMV were found in bilateral hippocampi and the left cerebellum. Subregionally, hippocampal volume reductions were more widespread and stronger in left-onset MTLE, whereas cerebellar associations were weaker and not significant after correction. Long-duration MTLE patients exhibited significant hippocampal GMV reductions compared with controls, but no significant cerebellar changes. Lateralization analysis revealed increasing ipsilateral hippocampal atrophy with longer disease duration, with no cerebellar lateralization detected.

CONCLUSION

This study maps hippocampal and cerebellar subregional alterations in MTLE, showing more consistent and extensive hippocampal associations with disease duration, particularly in left-onset cases. Cerebellar changes were subtler and lacked significant lateralization.Future longitudinal and multimodal studies are warranted to validate these patterns, clarify their clinical implications, and explore their potential as biomarkers for individualized prognosis and treatment planning.