Abstracts

Rationale: Surgical resection is the conventional treatment for intractable epilepsy due to cavernous malformations (CM) although stereotactic radiosurgery can be offered to some patients. Recently, stereotactic laser ablation (SLA) has been shown to be effective and safe for temporal lobe epilepsy. We present 2 patients who underwent SLA (Visualase Inc, Houston, TX) for the treatment of intractable epilepsy due to CM.Methods: Patient 1 was a 38 year-old, right-handed female with epilepsy since age 26 and failed 2 antiepileptic drugs (AEDs). She had monthly focal seizures consisting of behavioral arrest, oroalimentary automatisms, nonspecific hand movements, and confusion. MRI showed right mesial temporal CM. Video-EEG showed right posterior temporal seizure onset. Patient 2 was a 28 year-old right-handed male with epilepsy since age 20 and failed 2 AEDs. He had weekly focal seizures which started with an aura of flashing lights and nausea, followed by behavioral arrest, lip smacking, and confusion. Video- EEG showed right temporo-parieto-occipital localization. MRI showed right temporal CM. After standard presurgical workup and discussion in the multi-disciplinary case conference, both patients were offered either standard resective surgery or SLA. Because of simpler nature of the procedure without the need for craniotomy, both patients opted for SLA.Results: The patients were discharged the day after surgery. Patient 1 was seizure free for 7 months postoperatively. Post-ablation MRI showed shrinking of the lesion and a smaller size of the hemosiderin ring. When lamotrigine was tapered off, she had a complex partial seizure, prompting restarting of medication. Overall, she has had 3 focal seizures in 14 months of follow-up compared with monthly seizures preoperatively. Patient 2 developed right-sided weakness 3 days after surgery which resolved within 24 hours. He had a generalized tonic-clonic seizure while tapering down lamotrigine in the context of sleep deprivation, prompting restarting of lamotrigine. Post-ablation MRI showed no change in lesion. Overall, he has had 1 seizure in 12 months of follow-up compared with weekly seizures preoperatively.Conclusions: SLA for intractable epilepsy due to CM is feasible, effective, and safe. The long-term efficacy of the procedure in the context of incomplete ablation of the lesion needs further study.