Authors :
Presenting Author: Jonathan Goldstein, MD – Icahn School of Medicine at Mount Sinai
Madeline Fields, MD – Icahn School of Medicine at Mount Sinai
Anuradha Singh, MD – Icahn School of Medicine at Mount Sinai
Lara Marcuse, MD – Icahn School of Medicine at Mount Sinai
Leah Blank, MD – Icahn School of Medicine at Mount Sinai
Maite Lavega-Talbott, MD – Icahn School of Medicine at Mount Sinai
Fedor Panov, MD – Mount Sinai Health System
Saadi Ghatan, MD – Mount Sinai Health System
Jiyeoun (Jenna) Yoo, MD – Icahn School of Medicine at Mount Sinai
Rationale: Responsive neurostimulation (RNS), is a treatment option for patients with drug resistant epilepsy (DRE). RNS leads are placed near seizure foci where they detect seizures and deliver stimulation. For patients with >2 seizure foci or generalized onset seizures,
the application of RNS to thalamic nuclei is
postulated to modulate thalamocortical networks and reduce seizure activity. The centromedian nucleus (CMN) of the thalamus is an increasingly used target for RNS placement. We conducted a retrospective case series of patients treated with bilateral CMN RNS to describe their outcomes.
Methods: Adults and children who underwent bilateral CMN RNS lead placement between March 2018 and February 2023 in the Mount Sinai Health System (MSHS) were identified. The following information was collected: demographics, epilepsy type, prior epilepsy surgery, number of anti-seizure medications (ASMs) prescribed, length of follow up, serious adverse events and change in seizure frequency after surgery. Patients with ≥90% reduction in seizure frequency were considered super-responders, 50-89% were considered responders and < 50% reduction were considered non-responders. Reductions in seizure severity or duration were also documented.
Results: Twenty-four patients were included. Nineteen (79%) were male. Seven (29%) had generalized epilepsy, 9 (38%) had focal epilepsy and 8 (33%) had combined focal and generalized epilepsy. Sixteen (67%) had moderate or severe cognitive impairment and 8 (33%) had mild or no cognitive impairment. Fourteen (58%) had no prior epilepsy surgery and 10 (42%) had prior epilepsy surgery. Median follow up was 25 months. The number of ASMs prescribed was unchanged at last follow up in 14 (58%) patients, increased in 8 (33%), and decreased in 2 (8%). One patient had a serious adverse event which was post-operative infection, but recovered fully. Five (21%) patients were super-responders, 7 (29%) were responders, and 12 (50%) were non-responders. Of the 12 non-responders, 2 had a reduction in severity or duration of seizures. There was no difference in proportion of responders or super-responders by epilepsy type with 56% of patients with focal epilepsy, 29% with generalized epilepsy and 63% with combined focal and generalized epilepsy being responders or super-responders (p=0.39). Forty percent of patients with prior surgery and 57% of patients with no prior surgery were responders or super-responders, and no significant difference in outcome was found between these groups (p=0.40). Seventy-five percent of patients with mild or no cognitive impairment and 37.5% with moderate or severe cognitive impairment were responders or super-responders, and the difference in outcome between these groups approached but did not reach statistical significance (p=0.08).
Conclusions: Half the patients who underwent bilateral CMN RNS lead placement were considered responders or super-responders. There was one serious adverse event. Bilateral CMN RNS may be a safe and effective treatment for patients with multifocal, generalized onset or mixed DRE.
Funding: None