Abstracts

Rationale: In daily medical practice and welfare services for patients with epilepsy, the 1981 and 1989 International League Against Epilepsy (ILAE) classification ( 1981/1989 classification) have been widely used in Japan. In 2017, the classification of the epilepsies and operational classification of seizure types were proposed by ILAE (2017 classification). We aimed to clarify the clinical validity and utility of the 2017 classification. Methods: One hundred fifty consecutive patients who visited the adult epilepsy clinic in Department of Neurosurgery, National Hospital Organization Nara Medical Center and had been diagnosed as epilepsy were enrolled (84 males, age 38.3+-18.3 years, mean+-SD ). The 2017 classification was applied to each seizure type and epilepsy type to evaluate its usability. Results: There were 240 seizures, all of which were classified into sub-items. Seizure types that did not have corresponding items in the 1981 classification, such as epileptic spasms, were also classified. As for epilepsy classification, all of 150 patients were classified, and none fell into the category of unknown epilepsy. Four patients who had no suitable category according to the 1989 classification were newly classified as combined generalized and focal epilepsy. Out of 98 patients with focal epilepsy, 40% were described as having structural etiology, while no further details were obtained in others. Conclusions: The current study suggests that the 2017 classification is useful in representing patients' conditions and in planning comprehensive treatment and care in adults with epilepsy in Japan. On the other hand, locations of seizure foci should be listed in consideration of epilepsy surgery and in management of postoperative patients. Funding: No funding