Abstracts

Rationale: Duke University Hospital has had an active epilepsy surgery program since the early 1970’s. The volumes and types of surgeries performed have been impacted by many factors including personnel, available technology and techniques. Analyzing these trends has the potential to provide insights into the field of epilepsy surgery at both the local and broader level. Methods: The Duke Epilepsy Center database has been maintained prospectively since 2010. Other records, including logs from the Epilepsy Monitoring Unit and the electronic medical record, were used to obtain a nearly complete picture of epilepsy surgery procedures at Duke since 1979. This includes information about the presurgical evaluation (e.g., imaging data, functional studies such as intracarotid amytal testing and function MRI), intracranial monitoring (including type of electrodes/location), surgical procedures (type of procedure, location/lateralization and pathology). Results: From 1979 through 2017, 774 surgical resections, ablations or disconnection (callosotomy) procedures were performed at Duke University Hospital. The vast majority of cases in the 1980’s and 1990’s were temporal lobectomies; subsequently, while temporal lobectomies remain the most common procedure, extra-termporal cases have increased as have the number of cortectomies and thermal ablations. In the same time period, there were 351 cases that underwent intracranial EEG monitoring and approximately 129 neurostimulator implantations (some data missing). Before the mid-1990’s, the majority of intracranial cases utilized depth electrodes; subsequently, subdural electrodes were almost exclusively used until 2016, when stereo-EEG (SEEG) was used more routinely along with subdural electrodes. Data regarding details of the presurgical evaluation and pathology is still being analyzed. Conclusions: A wide variety of factors (both internal and external) have contributed to trends in epilepsy surgery at Duke University Hospital. Emergence of technologies like thermal ablation of epileptogenic tissue have altered approaches to certain patients, such as mesial temporal lobe epilepsy. External trends, like the emergence of SEEG in the U.S., have altered the approach to intracranial monitoring. The availability of specific personnel has also impacted both the volume and types of procedures being performed. Funding: None