[Cerebral cavernomas, epilepsy and seizures. Natural history and therapeutic strategy]

To review, from a retrospective series of 48 patients presenting with seizures associated with one or more supratentorial cavernoma(s), the natural history of the seizures and outcome according to medical and surgical treatment.

Patients were divided into two groups: group A included patients presenting with a single seizure or rare seizures (n=21), and group B patients having intractable epilepsy (n=27). All received antiepileptic drugs and 35 were operated on (12 in the group A and 23 in the group B). Stereo-EEG was performed in 8 patients in group B. Surgery included lesionectomy alone (n=16), resection of the cavernoma and perilesional tissue (n=7) or tailored corticectomy including the cavernoma (n=12).

The natural history of seizures was different in the two groups: mean age at seizure onset was 25 years in group B and 33 years in group A (p<0.05), seizures were partial in all patients in group B and 8 patients in group A (p<0.05). Seizure frequency and periodicity also varied. Prolonged seizure-free periods were observed. The cavernoma was temporal in 17 patients in group B and 4 patients in group A (p<0.01). In group A, seizure outcome was favorable following surgery or with antiepileptic medication only (7 patients out of 12 operated were seizure-free, as were 5 out of 7 non-operated). In group B, seizure outcome was better after surgery than with medication only (17 patients out of 23 operated were in Engel's Class I, while 3 patients of 4 non-operated patients had persisting seizures despite antiepileptic polytherapy).

Variations in seizure severity in patients harboring cavernomas suggest different therapeutic approaches. In case of unique or rare seizures, surgical resection of the cavernoma is appropriate, but benefits of surgery over antiepileptic medication in terms of seizure control remains unclear. Intractable epilepsy associated with cavernomas is better controlled after surgery rather than with medication only. In these patients, a detailed preoperative work-up is necessary and should be followed by wide resection associated or not with corticectomy, especially in the temporal lobe. Evaluation of outcome after surgery should consider the surgical strategy, antiepileptic medications and the patient's seizure history.