Monthly Case

A 16-year-old boy suffers from focal epilepsy since his 3^rd year of life. Epilepsy is manifesting with sleep-bound hypermotor seizures. He awakes from sleep – somtimes multiple times per night – with marked bilateral, but asymmetric movements of all extremities, consciousness is preserved, duration generally is shorter than 1 min. Every week, seizures occur in three to four nights. The described seizure type points to onset in the frontal lobe, and specifically in the supplementary motor area. 3T-MRI is normal, the patient suffers from cryptogenic partial epilepsy. In the last years, he was administered eight different antiepileptic drugs, current he is on levetiracetam 3,000 mg and lacosamide, 400 mg.

For many years, we spoke to the patient and his parents about the option of epilepsy surgery. When the patient was younger, his parents declined to make a decision for him. Now, the patient himself asked for the prerequisite presurgical diagnostic steps.

In long-term video-EEG with surface electrodes, seizure onset clearly could be seen in the right frontal lobe despite multiple movement artifacts. Interictal PET showed congruent pathology, with hypometabolism in right frontal structures. In a second step, the patient underwent invasive video-EEG monitoring with subdural electrodes covering the supplementary motor area on the right and the interhemispheric fissure. Within a couple of days, we recorded six habitual seizures with onset under four bordering electrodes. Electrical stimulation revealed non-eloquent cortex under these electrodes. With removal of electrodes, cortical structures beneath these electrodes were resected. Since the operation, the patient is seizure-free.

This case illustrates that also in patients with non-lesional frontal lobe epilepsy, resective surgery can be done successfully. However, case series demonstrate that seizure freedom rates are lower compared to temporal lobe or lesional epilepsy. Furthermore, it is highly likely that the patient would have benefited from surgery earlier in his life.

Cases of the months before