Glymphatic system dysfunction in epilepsy related to focal cortical dysplasia and its relationship with antiseizure medication response

Purpose

Glymphatic function has not been explored in patients with focal cortical dysplasia (FCD)-related epilepsy. This study aimed to investigate the glymphatic system's involvement in these patients and to evaluate its correlation with response patterns to different antiseizure medications (ASMs) using diffusion tensor imaging along the perivascular space (DTI-ALPS).

Methods

Fifty-two patients with FCD-related epilepsy (10 with drug-responsive epilepsy and 42 with drug-resistant epilepsy) and 24 healthy controls (HC) were included. Bilateral DTI-ALPS index were calculated and compared among drug-responsive epilepsy, drug-resistant epilepsy, and HC groups. Additionally, we analyzed correlations between the DTI-ALPS index and clinical characteristics.

Results

Compared to HC, patients with FCD-related epilepsy showed significantly lower DTI-ALPS index in the bilateral hemispheres (p < 0.001). Notably, a significant decrease in the DTI-ALPS index was noted in the hemisphere ipsilateral to the epileptogenic foci, compared to the contralateral hemisphere (p < 0.001). Further analysis revealed that, in patients with drug-resistant epilepsy, the ipsilateral DTI-ALPS index was significantly lower than the contralateral DTI-ALPS index (p < 0.001), whereas patients with drug-responsive epilepsy did not show a significant difference between ipsilateral and contralateral DTI-ALPS index. No significant correlations were found between the DTI-ALPS index and clinical characteristics such as age and duration of epilepsy.

Conclusion

Our findings suggest a correlation between glymphatic system dysfunction and patients with FCD-related epilepsy, particularly in drug-resistant patients.