Abstracts

Rationale: Resective surgery of posterior cortex epilepsy with ulegyria is established surgical treatment. Gross total lesionectomy renders good seizure outcome, while the risk of neurological deficit such as hemianopsia is not negligible. There is no evidence whether partial lesionectomy can achieve both good seizure outcome and functional preservation. In this study, we examined the efficacy of epilepsy surgery that is not necessarily remove the whole scar according to the result of intracranial EEG recording. Methods: A total of 9 patients harboring ulegyria in the posterior cortex who underwent resective surgery following intracranial electrode implantation were assigned in this study between 2014 and 2017. Mean age at surgery was 13 years (7 - 23 years). Mean disease duration was 5 years (2 - 10 years). Clinical features, seizure outcome and pre- and post-operative neurological deficits were examined. Results: Etiology of epilepsy were neonatal hypoglycemia in 4, brain trauma in 1, unknown in 4. All 4 patients with unknown etiology had unilateral lesion. The other 5 patients had bilateral lesions. Lesion was limited to the occipital lobe in 3, and extended beyond the occipital lobe in 5 patients. One patient had extra-occipital lesion only. Guided by the chronic intracranial EEG recording, partial resection of the scar were consequently performed in 7. Seizure free was achieved in 4 (44%), rare in 2 (22%), worthwhile improvement in 1 (11%) and no change in 2 (22%). New and/or worsening neurological deficits were observed in 3 patients (38%; quadrantoanopsia 2, hemianopsia 1) including one patient after total lesionectomy. Conclusions: Surgical treatment for intractable epilepsy with ulegyria is effective. Good seizure outcome can be achieved without new or worsening neurological deficits by tailored partial resection following intracranial EEG recording. Funding: This study was supported in part by an Intramural Research Grant (28-4: Clinical Research for Diagnostic and Therapeutic Innovations in Developmental Disorders) for Neurological and Psychiatric Disorders of NCNP.