Vagus Nerve Stimulation in Intractable Epilepsy
Cem Boluk , Cigdem Ozkara, Cihan Isler, Mustafa Uzan
Turk Neurosurg. 2022;32(1):97-102.
doi: 10.5137/1019-5149.JTN.33775-21.2.
Hot off the press – This study by Boluk et al. 2022 evaluated the efficiency and safety of vagus nerve stimulation (#VNS) in different types of #refractory epilepsy based on a single center experience at Istanbul University-Cerrahpasa, Turkey.
41 patients who underwent VNS implantation between 2005 and 2020 were enrolled.
The responder rate (defined as a ≥ 50% reduction in #seizure frequency) for the overall population increased over time, with 53.7% responders after 6 months, 68.3% responders in 12 months, and 75.6% responders in 18 months. Time-dependent changes in responder rates were further analysed based on epilepsy type (#focal, #generalized, or combined focal and generalized epilepsy; Table 1). The most favourable response to VNS Therapy was observed in patients with focal epilepsy, where 85.7% of the patients were responders at the 18-month follow-up (Table 1). Noteworthy, at the end of the follow-up, 48.8% of patients in the overall population achieved a >75% seizure reduction. Furthermore, the mean number of anti seizure medications (#ASM) decreased from 3.6 ± 0.6 (before VNS) to 3.2 ± 0.7 (follow-up: 12 months; P= 0.01).
Interestingly, despite the high responder rates reported in this study, the mean reported benefit ratio based on subjective evaluations by patients/caregivers was only 40.5% at the 12-month follow-up. A possible explanation for this observation might be too high expectations of patients/caregivers regarding the possibility to achieve seizure freedom.
According to the current result, VNS Therapy is a viable treatment option for focal, generalized, and combined epilepsy types and should be considered when epilepsy surgery has failed or is impossible to perform.
Table 1. VNS Responders rates during follow-up as stratified by epilepsy type.
Table 1. created by Go North Medical based on the data included in: Boluk C, Ozkara C, Isler C, Uzan M. Vagus Nerve Stimulation in Intractable Epilepsy. Turk Neurosurg. 2022;32(1):97-102. doi: 10.5137/1019-5149.JTN.33775-21.2. PMID: 34664698.