Vagus Nerve Stimulation (VNS) for Refractory Epilepsy: A 23-year Single Center Experience
Abstract number :
2.465
Submission category :
9. Surgery / 9C. All Ages
Year :
2024
Submission ID :
824
Source :
www.aesnet.org
Presentation date :
12/8/2024 12:00:00 AM
Published date :
Authors :
Presenting Author: Muhammad Usman Khalid, MBBS – University of Kentucky
Nausherwan Hussain, MS – University of Kentucky
Rachel Ward-Mitchell, RN – University of Kentucky
Timothy Ainger, PhD – University of Kentucky
Jordan Clay, MD – University of Kentucky
Julie Youssefi, MD – University of Kentucky
Sally Mathias, MD – University of Kentucky
Zabeen Mahuwala, MD – University of Kentucky
Zahra Haghighat, MD – University of Kentucky
Ghulam Q. Khan, MD – University of Kentucky
Ima Ebong, MD – University of Kentucky
Siddharth Kapoor, MD – University of Kentucky
Meriem K. Bensalem-Owen, MD, FACNS, FANA – University of Kentucky
Thomas Pittman, MD – University of Kentucky
Farhan A. Mirza, MD – University of Kentucky
Rationale: While the efficacy and safety of Vagus Nerve Stimulation is well-established in literature, the factors behind the variability in treatment response remain subject to debate. Our goal is to determine if certain factors (type and etiology of seizures, age at implantation, age of seizure onset, etc.) are associated with the effectiveness of VNS therapy in patients with refractory epilepsy.
Methods:
We conducted a retrospective analysis of 356 patients who presented to our center from 2000-2023 for VNS implantation. Data collected included age at implantation, age of first seizure, seizure type and etiology, seizure frequency before and after surgery, number of antiepileptic drugs (AEDs) before and after surgery, presurgical workup, and second surgery after VNS implantation. Responders were classified as those with at least a 50% improvement in seizure frequency.
Results:
Patients with drop attacks were significantly more likely to be responders than patients with other seizure types (p-value = 0.018). Our study showed no significant difference in post-VNS outcomes based on etiology and imaging findings. Patients with a baseline seizure frequency of 1-2/month (p-value = 0.001) and those with frequency of 1-2/year (p-value = 0.006) had significantly better McHugh scores than the other groups. Patients with baseline seizure frequencies of 1-2/year also were significantly more likely to be responders and had a significant decrease in antiepileptic drug burden post-surgery (p-value = 0.026). Similarly, patients who presented with > 1 seizure per day were significantly more likely to be responders after VNS. On sub-analysis, drop seizures, seizures >1/day, and 1-2 seizures/years were all significant in the generalized seizure group but not the focal seizure group.
Conclusions:
Our study shows that patients with refractory epilepsy who experience drop attacks and those with baseline seizure frequency towards either extreme received the most benefit from VNS implantation. Patients should undergo careful case selection to maximize post-surgical outcomes in terms of both seizure and medication burden.
Funding: No funding was received for this study.
Surgery