Abstracts

Rationale: De novo psychogenic nonepileptic seizures (PNES) following epilepsy surgery in patients without a prior history of nonepileptic seizure (NES) are well-described, but uncommon events.  Recent large retrospective studies indicate a prevalence of less than 4%, and while the majority suffer a PNES event in the first year after surgery, they seldom occur within weeks of surgery. Methods: This report illustrates the case of a 57 year old man with medically intractable localization related epilepsy secondary to mesial temporal sclerosis.  Three separate inpatient video electroencephalogram (EEG) studies over the course of 10 years had not revealed PNES and had localized the epileptogenic zone to the left temporal lobe.  He underwent a left subtemporal selective amygdalohippocampectomy without complication and was maintained on his pre-operative antiepileptic drugs. Results: Within 12 hours of surgery, the patient began exhibiting episodes with a different semiology than the preoperatively documented seizures.  These increased in frequency until the 4th post-operative day, when video-EEG revealed clear PNES with no electrographic evidence of the preoperative seizure disorder.  More than 25 events had occurred, with 11 captured on video-EEG.  Intervention including reassurance of the patient and family that the events did not represent epileptic seizures by the epileptologist and surgeon, as well as psychiatry consultation, resulted in immediate cessation of the events.  He has remained seizure-free at the time of this report, consistent with an Engle class 1 outcome. Conclusions: PNES become apparent in first few months post epilepsy surgery particularly in patients with medication refractory epilepsy and a prior history of psychiatric comorbidities. While rare, concentrated episodes of PNES activity may arise immediately after epilepsy surgery in patients without a prior history of PNES. This clinical vignette suggests that a suspicion of PNES must be taken into consideration should a patient develop cluster of seizures immediately after epileptic surgery. Funding: No funding