Abstracts

Rationale: To analyze the outcomes of functional hemispherectomies(FH) performed at Severance Children's Hospital in Seoul, Korea, from October 2003 to December 2011, among 468 epilepsy surgeries carried out in 388 patients Methods: A total of 52 patients have underwent functional hemispherectomies during the specified period and retrospective study of their medical charts was done. Two of the patients died due to surgical complications, one had expired within the initial three months after surgery, and one was lost to immediate follow up and a total of 48 cases were reviewed according to individual pre-operative conditions such as etiology of epilepsy, initial epilepsy classification, lead time to surgery, and post-operative outcomes were also reviewed to investigate improvement in seizure frequency, post-operative Engel and ILAE class, changes in antiepileptic medications, and more. To supplement the follow up information on the patients' latest status, additional questionnaire was asked to the patients' families by phone, which focused on changes in cognition, motor function, and quality of life for the patients. Results: The most common etiology of the patients was malformation of cortical development(23, 47.9%), with destructive encephalopathy(20, 41.7%), Sturge-Weber syndrome(5, 10.4%) next in order, with one case each for Rasmussen encephalitis, and Tuberous Sclerosis complex. For 40 out of the total 48 patients(83.3%), functional hemispherectomy was performed as final option as they have experienced seizure relapse after other epilepsy surgeries. Complications such hydrocephalus or hemorrhage have occurred 17 patients(35.4%). As only 22.9% (11 patients) were followed up to five years after FH, we have reviewed the percentage for each Engel and ILAE class among the total of patients followed up at each designated period, which were 3 months, and each year up to the 5th year, and have found that more than 50% of those followed up at each period were able to maintain Engel class 1A status. 34 out of 48 patients (70.8%) were able to reduce their initial antiepileptic medications and 15 (31.3%) actually have completely discontinued the medications altogether. 60.4% of the patients have replied to our questionnaire, which reported much improvement in 37.9% to 72.4% of the patients according to different area of cognition, such as control of hyperactivity to concentration. While 65.5% of the patients and families have answered to have motor deficit after the procedure, 93.1% have expressed overall satisfaction in improved seizure control and better quality of life. Conclusions: This study shows high seizure free rate and excellent cognitive outcome despite of inevitable motor deficit in functional hemispheretomy patients with less complications. Also for those epilepsy surgery patients who have relapsed afterwards, this procedure can be very viable option.