Extended resection of hemosiderin fringe is better for seizure outcome: a study in patients with cavernous malformation associated with refractory epilepsy.

BACKGROUND

Cerebral cavernous malformation (CCM) is frequently associated with intractable focal epilepsy. Epileptogenicity is usually attributed to the hemosiderin deposits. Extent of resection is a crucial issue for achieving good seizure outcome.

AIM

To assess whether seizure outcome is related to the extended resection (ER) of surrounding hemosiderin fringe brain tissue.

MATERIALS AND METHODS

Between April 2000 and April 2008, 132 patients with CCM and refractory epilepsy were scheduled for surgery based on the high-resolution magnetic resonance imaging (MRI) findings and intensive video-electroencephalogram (EEG) monitoring. All patients underwent pre- and post-operative MRI. Based on MRI findings patients were grouped into: ER group (ER, hemosiderin completely removed) and lesionectomy group (LE, hemosiderin not/partially removed). Post-operative seizure outcome was compared between the two groups based on Engel and the International League Against Epilepsy outcome scales.

RESULTS

At 1-year follow-up of the 86 patients in the ER group, 54 (74.4%) achieved seizure free outcome and in the LE group of the 46 patients, 20 (59.5%) achieved seizure-free outcome. At 5-year follow-up, 59.5% (25/42) of patients in ER group and 27.8% (5/18) of patients in LE group achieved seizure-free outcome. ER was not associated with increased neurological morbidity.

CONCLUSIONS

Our study suggests that complete removal of hemosiderin fringe brain tissue surrounding CCMs may improve short-term and long-term seizure outcome.