Abstracts

Sensory Symptoms During Centromedian Thalamic Responsive Neurostimulation

Abstract number : 1.333
Submission category : 9. Surgery / 9C. All Ages
Year : 2021
Submission ID : 1826713
Source : www.aesnet.org
Presentation date : 12/4/2021 12:00:00 PM
Published date : Nov 22, 2021, 06:56 AM

Authors :
Nora Daly, MS, PA-C - Massachusetts General Hostpital; Catherine Chu, MD, MA, MSSC – Director, Neonatal and Pediatric Continuous EEG Monitoring, Neurology, Massachusetts General Hospital; Sydney Cash, MD, PhD – Associate Professor, Neurology, Massachusetts General Hospital and Harvard Medical School, Neurology, Massachusetts General Hospital; Abigail Shaughnessy, RN – RNS RN, Neurology, Massachusetts General Hospital; Joel Oster – Director, Level 4 epilepsy center; Neurologist; Adult and Pediatric Sleep Medicine Attending, Tufts Medical Center; Alexandra Urban, MD – Director, UPMC Presbyterian Hospital EEG Laboratory, Neurology, UPMC; Mark Richardson – Director, Functional Neurosurgery, Neurosurgery, Massachusetts General Hospital

Rationale: Responsive neurostimulation (RNS) in the thalamus is used increasingly to treat drug-resistant multifocal, regional, and generalized epilepsy. Early experiences using centromedian-region RNS (CM-RNS) suggest it is a safe and effective treatment for patients with generalized epilepsy. The incidence and management of stimulation-induced side effects, however, have not been described.

Methods: Data were collected from chart review, review of the PDMS, and direct interrogation of the RNS device, in a cohort of 15 patients followed at 3 different centers. Thalamic lead locations were reconstructed using Lead-DBS and the Morel atlas.

Results: 9/15 patients experienced sensory symptoms with initial stimulation settings. All of these symptoms either resolved or were reduced to a minimally disruptive level with stimulation adjustments. All patients reported paresthesias (buzz/vibration feeling, or vague sensory change) in the face/head, arms, or both. All patients were initially programmed with bipolar configurations. Thresholds for developing side effects fell within the range of 0.3 mA-2.5 mA. Three programming techniques were used to relieve sensory symptoms. In three patients, stimulation was modified to distribute the stimulation and decrease the charge density on the contacts producing symptoms. In one patient, the frequency of stimulation was decreased and subsequent increases were tolerated with simultaneous increases in charge density. In 5 patients, leads remained on bipolar configuration but the contact pair was moved. In two cases, patients whose sensory symptoms did not completely resolve treated these symptoms like an artificial aura, that warned them when detections were increasing. All patients achieved at least Engel Class 3 outcomes. Lead reconstructions demonstrated relationships between stimulation locations and side effects.

Conclusions: Sensory side effects upon initiation of CM-RNS are common. Despite limitations on programming, all patients were clinical responders and all side effects either resolved or improved to tolerable levels. The potential ability of different thalamic locations to accommodate to higher stimulation settings over time is unknown.

Funding: Please list any funding that was received in support of this abstract.: None.

Surgery