Quantitative susceptibility mapping of iron deposition in sporadic cerebral cavernous malformation-related epilepsy

Objective: To evaluate iron deposition patterns in patients with cerebral cavernous malformation-related epilepsy (CRE) using quantitative susceptibility mapping (QSM) for detailed analysis of iron distribution associated with a history of epilepsy and severity.

Methods: This study is part of the Quantitative Susceptibility Biomarker and Brain Structural Property for Cerebral Cavernous Malformation Related Epilepsy (CRESS) cohort, a prospective multicenter study. QSM was used to quantify iron deposition in patients with sporadic cerebral cavernous malformation (CCMs). Lesions were segmented into intralesional, perilesional, and extralesional areas, with mean susceptibility values calculated for each subregion and analyzed in relation to epilepsy severity and duration.

Results: Among the 46 patients studied, those with a history of epilepsy had significantly higher iron deposition values in the perilesional (p =.012) and extralesional areas (p =.01), as well as a greater extent of iron deposition (p <.001) compared to those without epilepsy. The extent of iron deposition effectively distinguished patients with and without epilepsy, with an area under the curve (AUC) of 0.901 (95% confidence interval [CI]: 0.816-0.985). Among patients with epilepsy, iron deposition in the extralesional area was positively correlated with the severity of epilepsy (r² = 0.181, p =.043), and the extent of iron deposition was positively correlated with the duration of epilepsy (r² =.214, p =.026).

Significance: This study highlights QSM as a non-invasive tool for assessing iron deposition in CRE, identifying distinct subregional iron deposition patterns linked to epilepsy status and severity.