Background and Objective:
Rare Epilepsies and developmental epileptic encephalopathies (DEEs) that do not include channelopathies and brain malformation are often resistant to antiseizure medications (ASMs), and their management can be challenging. Moreover, specific tailored treatments for these conditions are not available, thus VNS Therapy™ may result in an early option after the failure of 2 ASMs. We investigate here the use of VNS in these groups.

Methods:
Among 68 patients receiving VNS Therapy at our center, we included those with rare DRE or DEE without major brain malformations or channelopathies having a follow-up > 1 year. For each patient we prospectively collected: age at the onset of seizures, age at the implant, length of the follow-up, seizure types (generalized, focal, both, spasms), results of the genetic tests, seizure outcomes with the McHugh scoring, number and type of concomitant ASMs and VNS stimulation parameters. All the patients reached the VNS target dose of 1.75 within 10 weeks of titration.

Conclusions:
Seizures outcomes after VNS Therapy™ in patients with DRE or DEE in the context of rare diseases, without major brain malformations or channelopathies, are limited in the literature and our study shows promising results both in seizure reduction and caregivers outcomes measures. These insights suggest that VNS Therapy™ might be a good early option for these kind of patients for which a specific treatment is not yet available.

Study Limitations:
This is a retrospective chart review in a limited number of patients

Notes:

1 Medical Affairs Department, Sorin Group Italia, LivaNova PLC-owned subsidiary, 20161, Milan, Italy; 2 Epilepsy Unit, Villa Santa Maria SCS, 22038 Como, Italy; 3 Neurosurgery Unit, San Gerardo Hospital, 20900 Monza, Italy; 4 Pediatric and Functional Neurosurgery, Department of Neuroscience, Padua University Hospital, 35127 Padova, Italy; *see Conflict of interest.