Medical Policy: 07.01.71 

Original Effective Date: January 2016 

Reviewed: January 2017 

Revised: January 2017 


Benefit Application:

Benefit determinations are based on the applicable contract language in effect at the time the services were rendered. Exclusions, limitations or exceptions may apply. Benefits may vary based on contract, and individual member benefits must be verified. Wellmark determines medical necessity only if the benefit exists and no contract exclusions are applicable. This medical policy may not apply to FEP. Benefits are determined by the Federal Employee Program.


This Medical Policy document describes the status of medical technology at the time the document was developed. Since that time, new technology may have emerged or new medical literature may have been published. This Medical Policy will be reviewed regularly and be updated as scientific and medical literature becomes available.



Responsive neurostimulation (RNS) for the treatment of partial epilepsy involves the use of 1 or more implantable electrode leads that serve as both a seizure detection and neurostimulation function. The device is programmed using a proprietary algorithm to recognize seizure patterns from electrocorticography output (an electroencephalogram made with electrodes that are in direct contact with the brain) and to deliver electrical stimulation with the goal of terminating a seizure before onset.


Neurostimulation devices are classified as one of two types: chronic programmed stimulation devices that administer stimulation at regular preprogrammed intervals (continuous or intermittent) and responsive neurostimulation (RNS) devices that deliver stimulation directly to the brain at the seizure focus only in response to device-detected, abnormal electrical brain activity. The chronic programmed stimulation methods available for treating epilepsy include vagus nerve stimulation (VNS). Responsive neurostimulation is intended to reduce seizures in patients diagnosed with partial onset of seizures, that are refractory to medical therapy and are not candidates for surgical resection.


There are two broad categories of seizures: focal (or partial) and generalized. Focal (partial) seizures involve only a portion of the brain, typically part of one lobe of one hemisphere. A focal (partial) seizure can be associated with impairment of consciousness or awareness (previously called complex partial seizure) or no impairment of consciousness (previously called simple partial seizures). A focal (partial) seizure can evolve over seconds into a tonic-clonic convulsion, also referred to as a secondary generalized seizure.


Focal (partial) seizures without impairment of consciousness can present in a variety of ways; however, within an individual patient, the seizures are usually stereotyped. Common focal seizures that do not alter awareness include both visible manifestations, such as jerking of a limb as well as subjective experiences perceived only by the patient, such as epigastric discomfort, fear, or an unpleasant smell. Such subject feelings are commonly referred to as auras. These seizures may be immediately followed by altered consciousness or awareness; this is usually manifested by a clouding of consciousness, staring, and repetitive motor behaviors, termed automatisms, such as swallowing, chewing or lip smacking. After such a seizure, the patient may experience confusion, fatigue, and throbbing headache. Individuals with altered awareness often have no recollection of their seizure, in fact,some patients are completely unware of all of their seizures.     


The primary treatment option for epilepsy is drug therapy consisting of one more antiepileptic drugs. However, many cases of epilepsy do not respond adequately to drug therapy. Medically refractory epilepsy is defined as “failure of adequate trials of two tolerated and appropriately chosen and used antiepileptic drug schedules to achieve sustained seizure freedom.” A second or third line option for these patients is surgical resection or transection of the seizure focus, which is considered to be the most effective therapy; however, some patients are not candidates for this type of surgery. Patients may not be candidates for surgery because seizure foci may be unidentifiable or because of overlap with vital areas of the brain. Treatment options are very limited for patients with medically refractory epilepsy who are not candidates for surgical resection. These patients may pursue alternative treatments which includes neurostimulation.


One responsive neurostimulation device, the Neuropace RNS System, is currently approved by FDA and is commercially available in the United States. The system consists of the implant and external components. The implant is the RNS neurostimulator (generator) and leads (tiny wires containing electrodes connected to the target areas of the brain). The neurostimulator is a battery powered microprocessor-controlled generator that is placed within the skull and beneath the scalp. It connects to one or two leads that are either inserted into the brain (depth lead) or placed on the brain surface in the area of the seizure focus (cortical strip lead). The external components include the programmer, remote monitor and magnet. The programmer is a laptop computer installed with a proprietary software program, which clinicians use to retrieve information from the neurstimulator and noninvasively program the neurostimulator through telemetry wand. A laptop computer installed with a proprietary software program and a telemetry wand compose the remote monitor. Using the telemetry wand (by swiping it over the implant site), a patient can transfer information from the neurostimulator to the laptop at home. The magnet allows patients to instruct the neurostimulator to record brain activity when seizure occurs or stop stimulation.


Before device implantation, the patient undergoes seizure localization, which includes video-EEG monitoring and magnetic resonance imaging for detection of epileptogenic lesions. Additional testing may also include EEG with intracranial electrodes, intraoperative or extraoperative stimulation with subdural electrodes, additional imaging studies, and/or neuropsychological testing and intracarotid amytal (Wada) testing. The selection and location of the leads are based on the location of seizure foci. Cortical strip leads are recommended for seizure on the cortical surface, while the depth leads are recommended for seizure foci beneath the cortical surface. The neurosurgeon performs a scalp incision and then drills two to four holes in the skull to allow for lead placement. The surgeon typically  implants the depth leads using specialized localization tools and planning software and implants the cortical strip leads on the brain surface under the dura. After securing the leads the surgeon removes the area of skull that conforms precisely to the neurostimulator (craniotomy) to accommodate the neurostimulator. The neurostimulator rests in a frame above the dura and does not touch the brain. After connecting the leads to the neurostimulator, the surgeon programs the neurostimulator for initial use and closes the incision. in the operating room to detect electrocorticographic activity (electroencephalogram made with electrodes that are in direct contact with the brain). Responsive therapy is initially set up using standard parameters (Neuropace recommended initial settings: frequency 200 Hz; pulse width 160 us; burst duration 100 ms; current 1.0 mA) from the electrodes from which electrical activity is detected. Over time, the responsive stimulation settings are adjusted on the basis of electrocorticography data, which are collected by the patient through interrogation of the device with the telemetry wand and transmitted to the data management system.


The patient data management system (PDMS) is a database for storing patient data that clinicians can access through the web. Clinicians and/or patients send data from the programmer or remote monitor to the PDMS regularly. Clinicians may use the PDMS to review a patient’s historical or current  information (e.g. programmed settings, detection and stimulation parameters, brain electrical activity recording) and create new stimulation and detection settings. The neurostimulator’s lifetime is 2.0 to 3.5 years with typical use, and the clinicians can use the programmer to monitor battery life.




The development of the RNS system arose out of observations related to the effects of cortical electrical stimulation for seizure location. It has been observed that electrical cortical stimulation can terminate induced and spontaneous electrographic seizure activity. Patients with epilepsy may undergo implantation of subdural monitoring electrodes for the purposes of seizure location, which at times have been used for neurostimulation to identify eloquent brain regions. Epileptiform discharges that occur during stimulation for localization can be stopped by a train of neighboring brief electrical stimulations.


In tandem with the recognition that cortical stimulation may be able to stop epileptiform discharges was the development of fast pre-ictal seizure prediction algorithms. These algorithms involve the interpretation of electrocorticographic data from detection leads over the cortex. The RNS process thus includes electrocorticographic monitoring via cortical electrodes, analysis of data through a proprietary seizure detection algorithm, and delivery of electrical stimulation via both cortical and deep implanted electrodes to attempt to halt a detected epileptiform discharge. 


The available literature related to the efficacy of RNS for partial epilepsy consists of 1 industry-sponsored randomized controlled trial (RCT), which was used for the device’s U.S. Food and Drug Administration (FDA) approval, with 2 year follow up available. In addition, there were several case series and case reports. The available RCT is well-designed and well-conducted; it reported that RNS is associated with improvements in mean seizure frequency in patients with refractory partial epilepsy with an absolute difference in change in seizure frequency of about 20% between groups, but noted that the percentage of patients who responded to treatment with at least 50% reduction in seizures did not differ from sham control. Overall, the results suggested a modest reduction in seizure frequency in a subset of patients. The number of adverse events (AEs) reported in the available studies is low. Although the data on AEs is limited by small numbers of patients, and follow-up beyond 2 years has not been reported, patients who are candidates for RNS are generally severely debilitated, and have few other treatment options, so the benefits are likely high relative to the risks. The evidence is sufficient to determine that the technology results in meaningful improvement in the net health outcomes and therefore, RNS may be considered medically necessary in patients with medication refractory partial epilepsy who are not candidates for epilepsy surgery.


Regulatory Status

November 2013, the NeuroPace RNS system (Neuropace Inc., Mountain View, CA) was approved by the FDA through the premarket approval process for the following indication:


“The RNS System is an adjunctive therapy in reducing the frequency of seizures in individuals 18 years of age or older with partial onset seizures who have undergone diagnostic testing that localized no more than 2 epileptogenic foci, are refractory to two or more antiepileptic medications, and currently have frequent and disabling seizures (motor partial seizures, complex partial seizures and/or secondary generalized seizures). The RNS System has demonstrated safety and effectiveness in patients who average 3 or more disabling seizures per month over the three most recent months (with no month with fewer than two seizures), and has not been evaluated in patients will less frequent seizures.”


Prior Approval:


Not applicable



Responsive neurostimulation (RNS) may be considered medically necessary for patients with partial epilepsy who meet ALL of the following criteria:

  • Are 18 years or older
  • Have a diagnosis of partial-onset seizures with 1 or 2 well localized seizure foci identified
  • Have an average of 3 or more disabling seizures (e.g. motor partial seizures, complex partial seizures, or secondary generalized seizures) per month over the prior 3 months
  • Are refractory to medical therapy (have failed 2 or more appropriate antiepileptic medications at therapeutic doses)
  • Are not candidates for focal resective epilepsy surgery (e.g. have an epileptic focus near eloquent cerebral cortex, have bilateral temporal epilepsy)
  • Do not have contraindications for RNS placement (contraindications for RNS placement include 3 or more specific seizure foci, presence of primary generalized epilepsy, or presence of a rapidly progressive neurologic disorder)

A replacement or revision of a responsive neurostimulation (generator, leads and/or battery) may be considered medically necessary for an individual who meets all of the above criteria and the existing device is no longer under warranty and cannot be repaired.     


Responsive neurostimulation (RNS) is considered investigational for all other indications as there is insufficient evidence to support the safety and effectiveness.


Procedure Codes and Billing Guidelines:

To report provider services, use appropriate CPT* codes, Alpha Numeric (HCPCS level 2) codes, Revenue codes and / or diagnosis codes.

  • 61863 Twist drill, burr hole, craniotomy or craniectomy with stereotactic implantation of neurostimulator electrode array in subcortical site (e.g. thalamus, globus pallidus, subthalmic nucleus, periventricular, periaqueductal gray), without use of intraoperative microelectrode recording; first array 
  • 61864 Each additional array (list separately in addition to primary procedure)
  • 61880 Revision or removal of intracranial neurostimulator electrodes
  • 61885 Insertion or replacement of cranial neurostimulator pulse generator or receiver, direct or inductive coupling; with connection to a single electrode array
  • 61886 with connection to 2 or more electrode arrays
  • 61888 revision or removal of cranial neurostimulator pulse generator or receiver
  • 95970 Electronic analysis of implanted neurostimulator pulse generator system (e.g. rate, pulse amplitude, pulse duration, configuration of wave form, battery status, electrode selectability, output modulation, cycling, impedance and patient compliance measurements); simple or complex brain, spinal cord, or peripheral (i.e. cranial nerve, peripheral nerve, sacral nerve, neuromuscular) neurstimulator pulse generator/transmitter, without reprogramming
  • 95971 Electronic analysis of simple spinal cord, or peripheral (i.e. peripheral nerve, sacral nerve, neuromuscular) neurostimulator pulse generator/transmitter, with intraoperative or subsequent programming
  • 95978 Electronic analysis of implanted neurostimulator pulse generator system (e.g. rate, pulse amplitude and duration, battery status, electrode selectability and polarity, impedance and patient compliance measurements), complex deep brain neurostimulator pulse generator/transmitter with initial or subsequent programming; first hour
  • 95979 Each additional 30 minutes after first hour (List separately in addition to code for primary procedure)    
  • C1767 Generator neurostimulator (implantable) non-rechargeable
  • C1778 Lead, neurostimulator (implantable)
  • C1787 Patient programmer, neurostimulator
  • C1816 Receiver and/or transmitter, neurostimulator (implantable)
  • C1820 Generator, neurostimulator (implantable), non high frequency with rechargeable battery and charging system
  • C1822 Generator, neurstimulator (implantable), high frequency with rechargeable battery and charging system
  • C1897 Lead, neurostimulator test kit (implantable)
  • L8679 Implantable neurostimulator, pulse generator any type
  • L8680 Implantable neurostimulator electrode, each
  • L8681 Patient programmer (external) for use with implantable programmable neurostimulator pulse generator, replacement only
  • L8682 Implantable neurostimulator radiofrequency receiver
  • L8683 Radiofrequency transmitter (external) for use with implantable neurostimulator radiofrequency receiver
  • L8685 Implantable neurostimulator pulse generator, single array, rechargeable includes extension
  • L8686 Implantable neurostimulator pulse generator, single array, nonrechargeable, includes extension
  • L8687 Implantable neurostimulator pulse generator, dual array, rechargeable, includes extension
  • L8688 Implantable neurostimulator pulse generator, dual array, nonrechargeable, includes extension
  • L8689 External recharging system for battery (internal) for use with implantable neurostimulator, replacement only


Selected References:

  • ECRI Emerging Technology Evidence Report. Closed Loop Implantable Neurostimulator (RNS System) for Reducing Seizures in Refractory Epilepsy. Published May 2015. Updated July 2016. 
  • FDA Summary of Safety and Effectiveness Data: RNS System 2013.
  • NeuroPace RNS System Patient Manual.
  • NeuroPace RNS System User Manual.
  • UpToDate Evaluation and Management of Drug Resistant Epilepsy, Joseph I Sirven, M.D., Topic last updated October 28, 2015.
  • Bergey Gregory, Morrell Martha, Mizrahi Eli, et. al. Long Term Treatment with Responsive Brain Stimulation in Adults with Refractory Partial Seizures. Neurology Feb 2015;84:810-817 
  • Heck CN, King-Stephens D, Massey AD, 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. Mar 2014;55(3):432-441
  • King-Stephens D, Mirro Emily, Weber Peter, et. al. Lateralization of Mesial Temporal Lobe Epilepsy with Chronic Ambulatory Electrocroticography. Epilepsia. 56(6):959-967.2015
  • PubMed. Morrell MJ. RNS System in Epilepsy Study Group. Responsive Cortical Stimulation for the Treatment of Medically Intractable Partial Epilepsy. Neurology 2011 Sept 27;77(13):1295-1304
  • PubMed. Meador KJ, Kapur R, Loring DW, et. al. Quality of Life and Mood in Patients with Medically Intractable Epilepsy Treated with Targeted Responsive Neurostimulation. Epilepsy Behav 2015 Apr 45;242-7
  • Sun FT, Morrell MJ. The RNS System: Responsive Cortical Stimulation for the Treatment of Refractory Partial Epilepsy. Expert Rev Med Devices 2014 Nov;11(6):563-72
  • Quigg Mark, Sun Felice, Fountain Nathan, et. al. Interrater Reliability in Interpretation of Electrocorticographic Seizure Detections of the Responsive Neurostimulator. Epilepsia. 56(6): 968-971,2015
  • de Tisi J, Bell GS, Peacock JL, et. al. The Long Term Outcome of Adult Epilepsy Surgery, Patterns of Seizure Remission, and Relapse: A Cohort Study. The Lancet.378(9800):1388-1395
  • Fridely J, Thomas JG, Navarro JC, et. al. Brain Stimulation for the Treatment of Epilepsy. Neurosurg Focus 2012 Mar;32(3)E13
  • Fisher RS. Therapeutic Devices for Epilepsy. Ann Neurol. Feb 2012;71(2):157-168
  • Anderson WS, Kossoff EH, Bergey GK, et. al. Implantation of a Responsive Neurostimulator Device in Patients with Refractory Epilepsy. Neurosurg Focus 2008 Sep;25(3):E12
  • Noe K, Sulc V, Wong-Kisiel L, et. al. Long-Term Outcomes after Nonlesional Extratemporal Lobe Epilepsy Surgery. JAMA Neurol. Aug 2013;70(8):1003-1008
  • American Epilepsy Society. Study Demonstrates Safety and Efficacy of NeuroPace RNS System in Adults with Intractable Seizures. Published December 9, 2013
  • Costa J, Fareleira F, Ascencao R, et al. Clinical comparability of the new antiepileptic drugs in refractory partial epilepsy: a systematic review and meta-analysis. Epilepsia. Jul 2011;52(7):1280-1291. PMID 21729036
  • Kossoff EH, Ritzl EK, Politsky JM, et al. Effect of an external responsive neurostimulator on seizures and electrographic discharges during subdural electrode monitoring. Epilepsia. Dec 2004;45(12):1560-1567. PMID 15571514
  • Anderson WS, Kossoff EH, Bergey GK, et al. Implantation of a responsive neurostimulator device in patients with refractory epilepsy. Neurosurg Focus. Sep 2008;25(3):E12. PMID 18759613
  • DiLorenzo DJ, Mangubat EZ, Rossi MA, et al. Chronic unlimited recording electrocorticography-guided resective epilepsy surgery: technology-enabled enhanced fidelity in seizure focus localization with improved surgical efficacy. J Neurosurg. Jun 2014;120(6):1402-1414. PMID 24655096
  • Spencer D, Gwinn R, Salinsky M, et al. Laterality and temporal distribution of seizures in patients with bitemporal independent seizures during a trial of responsive neurostimulation. Epilepsy Res. Feb 2011;93(2-3):221-225. PMID 21256715
  • Loring DW, Kapur R, Meador KJ, et al. Differential neuropsychological outcomes following targeted responsive neurostimulation for partial-onset epilepsy. Epilepsia. Nov 2015;56(11):1836-1844. PMID 26385758 
  • Meador KJ, Kapur R, Loring DW, et al. Quality of life and mood in patients with medically intractable epilepsy treated with targeted responsive neurostimulation. Epilepsy Behav. Apr 2015;45:242-247. PMID 25819949
  • Cox JH, Seri S, Cavanna AE. Clinical utility of implantable neurostimulation devices as adjunctive treatment of uncontrolled seizures. Neuropsychiatr Dis Treat. 2014;10:2191-2200. PMID 25484587
  • Bergey GK, Morrell MJ, Mizrahi EM, et al. Long-term treatment with responsive brain stimulation in adults with refractory partial seizures. Neurology. Feb 24 2015;84(8):810-817. PMID 25616485
  • Lee B, Zubair MN, Marquez YD, et al. A single-center experience with the neuropace rns system: a review of techniques and potential problems. World Neurosurg. Sep 2015;84(3):719-726. PMID 25940211
  • Child ND, Stead M, Wirrell EC, et al. Chronic subthreshold subdural cortical stimulation for the treatment of focal epilepsy originating from eloquent cortex. Epilepsia. Mar 2014;55(3):e18-21. PMID 24571166
  • National Epilepsy Foundation. Responsive Neurostimulation. May 2014.
  • International Neuromodulation Society. Closed Loop Stimulation for Epilepsy.
  • UpToDate. Overview of the Management of Epilepsy in Adults. Steven C. Schachter M.D. Topic last updated October 12, 2016.
  • UpToDate. Surgical Treatment of Epilepsy in Adults. Gregory D. Cascino M.D. Topic last updated November 7, 2016.
  • UpToDate. Treatment of Seizures and Epilepsy in Older Adults. Hyunmi Choid M.D., M.S., Anil Mendiratta M.D. Topic last updated July 15, 2016.
  • UpToDate. Vagus Nerve Stimulation Therapy for the Treatment of Epilepsy. Steven C. Schachter M.D. Topic last updated October 13, 2016.
  • Thomas G, Jobst B. Critical review of the responsive neurostimulator system for epilepsy. Medical Devices: Evidence and Research 2015:8 405-411


Policy History:

  • January 2017 - Annual Review, Policy Revised
  • January 2016 - New policy

Wellmark medical policies address the complex issue of technology assessment of new and emerging treatments, devices, drugs, etc.   They are developed to assist in administering plan benefits and constitute neither offers of coverage nor medical advice. Wellmark medical policies contain only a partial, general description of plan or program benefits and do not constitute a contract. Wellmark does not provide health care services and, therefore, cannot guarantee any results or outcomes. Participating providers are independent contractors in private practice and are neither employees nor agents of Wellmark or its affiliates. Treating providers are solely responsible for medical advice and treatment of members. Our medical policies may be updated and therefore are subject to change without notice.


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