Abstract
Objective Fast ripples (FR, 250–500 Hz) are proposed biomarkers of the epileptogenic zone on the basis of several retrospective reports linking postoperative seizure freedom to their complete resection. There are no clinical trials or prospective reports validating the use of FR as characterized by electrocorticography (ECoG), to guide the scope of epilepsy surgery, and to inform prognosis thereafter. We set out to prospectively evaluate the utility of FR resection to predict postoperative epilepsy outcomes, and examine the feasibility of “live” intraoperative FR ascertainment. Methods FR were prospectively reviewed in 30 consecutive pediatric cases including 11 reviewed “live” during surgery. Intraoperative ECoG studies were recorded at 2000 Hz sampling rate, interpreted conventionally to guide surgical resection, and visually inspected for FR. Seizure outcome was tallied for all 30 children. Results Median age at surgery was 9.1 years (interquartile range [IQR] 4.7–13.2), median ECoG duration was 10.5 min (IQR 8.0–13.2), and median postoperative follow-up was 58.4 months (IQR 25.7–79.0). FR were identified in 24 of 30 ECoG studies. The incomplete resection of FR was strongly linked to postoperative seizures (hazard ratio 11.6, p = 0.005). “Live” ECoG review in the operating room to ascertain FR proved feasible and did not differ from conventional FR ascertainment. Significance: In a prospective fashion, including “live” review, FR were detected in 80% of pediatric ECoG studies, and incomplete resection of FR cortex predicted postoperative seizures. These findings extend the notion that interictal FR are surrogate markers of the epileptogenic zone, and that their intraoperative localization could be used to inform prognosis and guide surgical resections in children.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 344-351 |
| Number of pages | 8 |
| Journal | Epilepsy Research |
| Volume | 127 |
| DOIs | |
| State | Published - Nov 1 2016 |
Funding
Dr. Mathern serves as Co-Editor in Chief for Epilepsia and is on the editorial boards of Neurology, Epileptic Disorders, Epilepsy & Seizures, and Epilepsy Research, on the Data Management Committee of Neuropace, Inc; and receives research support from the NIH (R01NS038992[PI]), the RE Children's Project, and the Davies/Crandall Endowment. He has received funds to support travel in association with his volunteer work from the International League Against Epilepsy (ILAE). Dr. Hussain has received research support from the Epilepsy Therapy Project, the Milken Family Foundation, the Hughes Family Foundation, the Elsie and Isaac Fogelman Endowment, Eisai, Lundbeck, Insys Therapeutics, GW Pharmaceuticals, and the NIH (R34MH089299), and has served on the scientific advisory boards of Questcor Pharmaceuticals, Mallinckrodt Pharmaceuticals, and Upsher-Smith Laboratories, and as a consultant to Eisai. Dr. Wu serves on the professional advisory board for the Tuberous Sclerosis Alliance; has received honoraria from and serves on the scientific advisory board and the speakers’ bureau for Novartis Pharmaceuticals Inc. and Lundbeck; and has received research support from the Tuberous Sclerosis Alliance, Novartis Pharmaceuticals Inc., Today and Tomorrow Children’s Fund, Department of Defense/Congressionally Directed Medical Research Program, and the NIH (P20NS080199 [Co-I], U01NS082320 [Co-I], R01NS082649 [PI]), U54NS092090 [Co-I], and U01 NS092595 [Co-I]). This work was supported by the National Institutes of Health [R01 NS 051637] and the Today and Tomorrow Children’s Fund.
Keywords
- EEG
- Epilepsy surgery
- High frequency oscillation
- Intraoperative electrocorticography
- Seizure outcome
ASJC Scopus subject areas
- Clinical Neurology
- Neurology