The NeuroPace RNS® System and Surgical Options

Ryan B. Kochanski, MDClinical Fellow in Functional and Epilepsy Surgery

Rush University Medical Center

Sepehr Sani, MDAssistant Professor

Rush University Medical Center

November 12, 2016

Disclosures• None

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Objectives• Provide an overview of the RNS system

• Discuss indications for implantation

• Describe the surgical procedure

• Discuss long term outcome data

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NeuroPace RNS® System

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What is Responsive Neurostimulation?

• Two major functions that comprise the device:– Recording of brain wave

activity i.e. long term EEG recording

– Electrical stimulation at the location of the implanted electrode to abort a seizure when it is detected

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Continuous Long Term Recording

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• The device continuously records and stores the electrophysiological information from the electrode(s) (EEG data)

• This stored data can be then transferred to an online Patient Data Management System using the interrogating device

• Physicians can access and analyze this information remotely

Stimulation

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• The device can be programmed to deliver an electrical stimulus when seizure activity is recognized in order to “break” the seizure

• Stimulation settings can be adjusted by the physician depending on response

• Different than VNS which provides non-selective stimulation

Indications for Surgery• 18 years of age or older• Poor seizure control despite 2 or

more anti-seizure medications• Frequent and disabling partial onset

seizures localized to 2 or less foci based on preoperative testing

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Pre-Operative Planning• An MRI of the brain is obtained as an outpatient• On the day of surgery, a head frame is placed on the patient and a CT scan is obtained• The MRI and CT scan are then merged using a planning software• The planning software is used to create a surgical plan for the placement of the lead(s)

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Surgery

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Surgery – Battery placement

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Case Illustration • 25 year old male with a history of epilepsy since childhood who

underwent a left temporal lobectomy in ‘03 and left vagal nerve stimulator placement in ‘06

• Seizures are characterized by loss of awareness and arrest of activity, where he suddenly stops and stands still followed by hand shaking or finger tapping.

• EEG – Continuous, irregular, right greater than left temporal slow wave activity with occasional epileptiform discharges on the right and left.

• Findings suggestive of bilateral temporal epilepsy.

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Surgical Plan

Bilateral Parahippocampal Depth Leads

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Post-Operative Imaging

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Surgical Complications

15Bergey et al. Neurology. 2016

Long term outcomes

16Bergey et al. Neurology. 2016

C.U.R.E.

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• Continuous recording and storage of EEG data can allow for better localization of seizure activity

• With better seizure localization, some patients who were initially not thought to be candidates for resective surgery have become surgical candidates

Q & A

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References • Bergey GK, Morrell MJ, Mizrahi EM, Goldman A, King-Stephens D,

Nair D, et al.: Long-term treatment with responsive brain stimulation in adults with refractory partial seizures. Neurology 2015 Feb 24;84:810–817.

• DiLorenzo DJ, Mangubat EZ, Rossi MA, Byrne RW: Chronic unlimited recording electrocorticography-guided resective epilepsy surgery: technology-enabled enhanced fidelity in seizure focus localization with improved surgical efficacy. J Neurosurg 2014 Jun;120:1402–1414.

• Heck CN, King-Stephens D, Massey AD, Nair DR, Jobst BC, Barkley GL, et al.: Two-year seizure reduction in adults with medically intractable partial onset epilepsy treated with responsive neurostimulation: final results of the RNS System Pivotal trial. Epilepsia 2014 Mar;55:432–441.

• Morrell MJ, RNS System in Epilepsy Study Group: Responsive cortical stimulation for the treatment of medically intractable partial epilepsy. Neurology 2011 Sep 27;77:1295–1304.

• Sun FT, Morrell MJ: The RNS System: responsive cortical stimulation for the treatment of refractory partial epilepsy. Expert Rev Med Devices 2014 Nov;11:563–572.

• Thomas GP, Jobst BC: Critical review of the responsive neurostimulator system for epilepsy. Med Devices (Auckl) 2015 Oct 1;8:405–411.

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