ModifiedUnitedHealthcarePolicy CS129PA.S

Vagus and External Trigeminal Nerve Stimulation (for Pennsylvania Only)

Policy governing coverage and medical necessity of implantable vagus nerve stimulators and noninvasive/transcutaneous vagus and trigeminal nerve stimulation devices for members in Pennsylvania.

Policy Summary

PayerUnitedHealthcare

PolicyVagus and External Trigeminal Nerve Stimulation (for Pennsylvania Only)

Policy CodePolicy CS129PA.S

Change TypeRevisions to device listings and documentation requirementsadded coverage governance language

Effective DateMar 1, 2026

Next Review DateN/A

Key ActionEnsure medical records fully document history, exam, and diagnostic tests to support medical necessity when requesting coverage.

SourceLink

POLICY UPDATE CHANGES

Revised list of unproven and not medically necessary devices; replaced specific example wording for transcutaneous vagus nerve stimulation with broader terminology 'transcutaneous (non-implantable) vagus nerve stimulation devices'.

Added language clarifying that benefit coverage is determined by federal, state, or contractual requirements and applicable laws which may require coverage for a specific service.

Added and clarified requirements that medical records documentation may be required to assess whether the member meets clinical criteria and must fully support medical necessity.

Updated related policy link/title for Transcranial Magnetic Stimulation for Treating Physical Health Conditions (for Pennsylvania Only).

Pennsylvania onlyGeographic applicability

No serious device ADEs reportedSafety signal

5 trials

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RCT evidence (VNS adjunctive)

5223 individualsStudies pooled

Limited/insufficientMany indications - evidence

InsufficienttVNS evidence

Coverage Criteria and Evidence-based Stance

Implantable Vagus Nerve Stimulator — Medical Necessity for Epilepsy

Covered when ALL of the following are met:

Implantable VNS coverage criteria: 1) Medically refractory epileptic seizures with failure of two or more trials of single or combination antiepileptic drug therapy or intolerable side effects of antiepileptic drug therapy; 2) The individual is not a candidate for epilepsy surgery, has failed epilepsy surgery, or refuses epilepsy surgery after Shared Decision Making discussion; 3) No history of left or bilateral cervical vagotomy (FDA contraindication).

Devices and Indications Considered Unproven/Not Medically Necessary

Not medically necessary (unproven) for the following device types and indications:

Nonimplantable and external devices: Transcutaneous (non-implantable) vagus nerve stimulation devices for preventing or treating all indications; External or transcutaneous trigeminal nerve stimulation devices for preventing or treating all conditions including but not limited to ADHD, depression, epilepsy, and headache.

Condition-specific coverage logic

Coverage stance differs by indication and is guided by evidence summaries and guidelines:

Epilepsy (adjunctive implanted VNS): Consider VNS for individuals with drug-resistant epilepsy when seizures are not adequately controlled after multiple antiseizure medications and when resective epilepsy surgery is not viable or declined.

Supports guideline recommendation from Epilepsy Society and NICE.

Treatment-Resistant Depression (implanted VNS): Evidence is mixed: some long-term observational registry data and meta-analyses report improved outcomes with adjunctive VNS in severe treatment-resistant depression, but randomized sham-controlled trials have not consistently met primary endpoints; use should be limited to treatment-resistant cases with special governance and further research.

NICE recommends use only with special arrangements; RCT evidence limited.

Cluster Headache (noninvasive VNS): Noninvasive VNS (nVNS) shows benefit over sham for episodic cluster headache (eCH) in randomized trials and meta-analysis but not for chronic cluster headache (cCH); longer-term data are limited.

Evidence supports nVNS for eCH but is inconsistent for cCH; longer-term data limited.

Coverage by indication

Coverage and medical necessity depend on indication and supporting evidence; summarized distinctions follow.

Episodic cluster headache (eCH): Evidence from randomized trials (Silberstein et al. 2016a) and meta-analysis showed statistically significant higher response and sustained response rates with nVNS versus sham for episodic cluster headache; safety profile favorable; may be considered clinically beneficial for eCH in select patients.

[[chunk 36]]

Chronic cluster headache (cCH): Randomized trial data did not show benefit of nVNS over sham for chronic cluster headache and interpretation is limited; evidence does not support routine coverage for cCH.

[[chunk 36]]

Other indications (epilepsy beyond implantable VNS, ADHD, depression, cardiac, tinnitus, etc.): Evidence is preliminary, heterogeneous, and generally insufficient to establish safety and effectiveness; these indications are not supported for routine coverage except in research or highly selected cases.

[[chunk 38],[chunk 51]]

Evidence summaries by indication

Evidence and guideline summaries for select indications

ADHD - eTNS: McGough et al. (2019) reported a blinded sham-controlled trial showing TNS efficacy for ADHD with an effect size similar to non-stimulant medications, but durability and broader safety data are limited; AAP states eTNS cannot be recommended for routine ADHD treatment.

RCT positive but guideline does not endorse routine use

Acute migraine - eTNS: Chou et al. (2019) double-blind RCT showed one-hour external trigeminal nerve stimulation reduced pain intensity versus sham for acute migraine; small sample and baseline imbalances noted but primary outcome positive; NICE advises use for acute migraine only with special arrangements for governance/consent/audit or research.

NICE: adequate evidence for acute migraine but recommends special arrangements

Depression - TNS: Generoso et al. (2019) randomized phase II study (n=24) showed significant HDRS-17 improvement after a 10-day TNS protocol with sustained effect at one month, but small sample size and short follow-up limit certainty.

Early-phase positive signals but limited data

Revisions and Documentation-related Criteria

Policy revisions clarify device listings and documentation requirements; refer to policy body for full coverage criteria.

Device list revision: Replaced specific example wording for transcutaneous vagus nerve stimulation with the broader term 'transcutaneous (non-implantable) vagus nerve stimulation devices', which affects listings of unproven/not medically necessary devices; see full policy for device-specific decisions.

This change affects how unproven/not medically necessary devices are listed; see full policy for device-specific coverage decisions.

Documentation requirements: Medical records must fully support medical necessity with relevant medical history, physical examination findings, and results of pertinent diagnostic tests or procedures; documentation must be legible, maintained in the patient record, and made available upon request. Failure to provide adequate documentation may prevent assessment or lead to denial.

Failure to provide may prevent assessment or lead to denial.

Implantable vagus nerve stimulation (VNS) is proven and medically necessary for epilepsy only when established clinical criteria are met; it is unproven and not medically necessary for other conditions. The policy lists multiple examples of non‑epilepsy indications for which implantable VNS is considered not medically necessary due to insufficient evidence, including but not limited to Alzheimer’s disease, anxiety, autism spectrum disorder, chronic pain, cluster headaches, depression, fibromyalgia, heart failure, migraines, obsessive‑compulsive disorder, sleep disorders, and upper limb impairment related to stroke. Providers should refer to the full policy for the complete list of excluded conditions and required documentation when evaluating implantable VNS for non‑epilepsy indications.

Transcutaneous (non‑implantable) vagus nerve stimulation (tVNS/nVNS) devices are listed in the policy as unproven and not medically necessary for preventing or treating all indications because current studies are limited by small sample sizes, heterogeneous designs, and insufficient long‑term outcome data. Larger, higher‑quality trials are required to establish safety and effectiveness before these non‑implantable VNS devices are considered medically necessary for a specific condition.

External/transcutaneous trigeminal nerve stimulation (eTNS) and noninvasive vagus nerve stimulation (nVNS/tVNS) have been investigated for indications beyond migraine and cluster headache, but the policy states these uses are investigational/insufficient evidence. Evidence syntheses and trial data are heterogeneous and of low to moderate quality, so routine coverage for indications such as ADHD, depression, epilepsy outside specified trials, cardiac conditions, tinnitus, and others is not supported without further high‑quality data.

A systematic review (Boon et al., 2018) and related evidence summaries found insufficient data to support trigeminal nerve stimulation (TNS) for drug‑resistant epilepsy. The review concluded that current noninvasive neurostimulation studies, including TNS, do not provide adequate evidence of efficacy for DRE and additional data collection is warranted.

The policy was revised to update the list of devices considered unproven and not medically necessary. As part of this change, specific example wording for non‑implantable vagus nerve stimulation was broadened: the phrase referencing a named device example was replaced with the more general term “transcutaneous (non‑implantable) vagus nerve stimulation devices” to reflect device‑class terminology in the unproven/not medically necessary listing.

Implantable VNS remains unproven for conditions beyond epilepsy and is therefore not medically necessary for those indications; the policy cross‑references a full list of excluded conditions in the Coverage Rationale. The policy also specifies that transcutaneous and external nerve stimulation devices are considered unproven for broad sets of indications; see the revised device list in the policy for the complete unproven/not medically necessary device listings.

The policy restates that transcutaneous (external, non‑implantable) VNS is not supported for many indications because study limitations and inconsistent results prevent conclusions about safety and effectiveness. Examples highlighted include migraine and a range of non‑headache conditions; larger, standardized trials with clear outcome measures are needed before routine coverage can be recommended.

External/transcutaneous trigeminal nerve stimulation and some applications of noninvasive VNS (nVNS/tVNS) are identified in the policy as investigational or having insufficient evidence for many conditions beyond selected migraine and episodic cluster headache settings. The evidence base is described as low quality and heterogeneous, and routine coverage for these external neuromodulation therapies is not supported outside of research or special‑arrangement contexts.

The American Academy of Pediatrics reviewed the evidence for external trigeminal nerve stimulation in ADHD and determined that eTNS cannot be recommended as a treatment for ADHD because available supporting evidence is sparse and does not approach the strength of established medication and behavioral therapies.

Editorially, the policy now uses broader terminology when referring to non‑implantable vagus nerve stimulation devices. The revision replaces a specific device example with the general term “transcutaneous (non‑implantable) vagus nerve stimulation devices” to reflect device‑class listing in the unproven/not medically necessary section.

Applicable Procedure, Supply, and Device Codes

Applicable CPT/HCPCS (service codes)mixed

61885	Insertion or replacement of cranial neurostimulator pulse generator or receiver, direct or inductive coupling; with connection to a single electrode array.
61886	Insertion or replacement of cranial neurostimulator pulse generator or receiver, direct or inductive coupling; with connection to 2 or more electrode arrays.
64553	Percutaneous implantation of neurostimulator electrode array; cranial nerve.
64568	Open implantation of cranial nerve (e.g., vagus nerve) neurostimulator electrode array and pulse generator.
64570	Removal of cranial nerve (e.g., vagus nerve) neurostimulator electrode array and pulse generator.
A4541	Monthly supplies for use of device coded at E0733.
E0733	Transcutaneous electrical nerve stimulator for electrical stimulation of the trigeminal nerve.
E0735	Noninvasive vagus nerve stimulator.
E0770	Functional electrical stimulator, transcutaneous stimulation of nerve and/or muscle groups, any type, complete system, not otherwise specified.
E1399	Durable medical equipment, miscellaneous.

Applicable DME/HCPCS L-codesHCPCS

L8679	Implantable neurostimulator, pulse generator, any type.
L8680	Implantable neurostimulator electrode, each.
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, non-rechargeable, includes extension.
L8687	Implantable neurostimulator pulse generator, dual array, rechargeable, includes extension.
L8688	Implantable neurostimulator pulse generator, dual array, non-rechargeable, includes extension.

Implantable Vagus NNS FDA product codesmixed

LYJ	FDA product code referenced for implantable VNS PMA listings
MUZ	FDA product code referenced for implantable VNS PMA listings
QPY	FDA product code referenced for implantable VNS PMA listings

Transcutaneous Vagus FDA product codesmixed

PKR	FDA product code referenced for transcutaneous (non-implantable) VNS
QAK	FDA product code referenced for transcutaneous (non-implantable) VNS

External Trigeminal Nerve Stimulation FDA product codesmixed

PCC	FDA product code referenced for external/transcutaneous trigeminal nerve stimulation
QGL	FDA product code referenced for external/transcutaneous trigeminal nerve stimulation

Referenced tools and evidence resourcesmixed

INTERQUAL®

Third-party criteria tool referenced for administering benefits

Coding thresholds — metadata note

Numeric thresholds presentNo numeric thresholds or numeric cutpoints are specified in the cited coding and thresholds chunks.

Operational implicationCoding and device product-code listings are informational; evaluate coding/coverage using full policy criteria and documentation.

Documentation noteRefer to the policy's documentation requirements for submission expectations; absence of numeric thresholds does not change medical necessity criteria.

Prior Authorization, Documentation, and Operational Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required for implantable and certain neuromodulation devices and related procedures. Prior authorization requests must include documentation that the member meets clinical criteria (see Coverage Rationale) and, where applicable, that surgical options are not viable or have failed and that appropriate medication trials have been attempted. Lack of required information may delay review or result in denial.

Provider must obtain prior authorization before scheduling implantation or billable procedural services listed in Applicable Codes.
When applicable, include documentation that resective epilepsy surgery is not an option, was unsuccessful, or was declined after shared decision-making discussion.
Medical necessity determinations remain subject to federal, state, and contractual requirements and applicable laws which may mandate coverage despite policy limits.

Documentation Required

Limited Evidence — Governance and Authorization

Background and Evidence Context

Vagus nerve stimulation (VNS) delivers electrical impulses to the brain via the vagus nerve using a surgically implanted generator and lead system. Proposed mechanisms include modulation of neurotransmitter release, alterations in cerebral blood flow, and effects on EEG activity. Implantable VNS devices have FDA approvals for specific indications (notably epilepsy and some treatment‑resistant depression contexts), whereas transcutaneous VNS and external trigeminal stimulation are noninvasive alternatives under investigation and differ by anatomy, delivery site (auricular or cervical for tVNS; supraorbital for eTNS), and evidence base.

Definitions and Terminology

Shared Decision Making — definition

DefinitionShared Decision Making is a collaborative process in which a provider/clinician and a patient (including caregivers and family) work together to make healthcare decisions, considering evidence-based information, provider experience, and the patient’s values, goals, preferences, and circumstances.

Key elementsCompares benefits, harms, and risks of options and discusses what matters most to the patient (AHRQ, About Shared Decision Making, 2023).

DocumentationPolicy recommends documenting shared decision-making discussions when offering VNS (per NICE-aligned guidance referenced in the policy).

AAN Level C — evidence designation

AAN Level C meaningIndicates possibly effective, ineffective, or harmful (or possibly useful/predictive or not useful/predictive) for the given condition in the specified population.

Policy Revision History

2026-04-01policy_update

Updated related policy reference link for Transcranial Magnetic Stimulation for Treating Physical Health Conditions (Pennsylvania only).

2026-03-01material_change

Revised list of unproven and not medically necessary devices by replacing example wording with broader term 'transcutaneous (non-implantable) vagus nerve stimulation devices' and added statement that benefit coverage is determined by federal, state, or contractual requirements and applicable laws which may require coverage for a specific service.

2026-03-01documentation_requirement_added

Policy Summary

PayerUnitedHealthcare

PolicyVagus and External Trigeminal Nerve Stimulation (for Pennsylvania Only)

Policy CodePolicy CS129PA.S

Change TypeRevisions to device listings and documentation requirementsadded coverage governance language

Effective DateMar 1, 2026

Next Review DateN/A

Key ActionEnsure medical records fully document history, exam, and diagnostic tests to support medical necessity when requesting coverage.

SourceLink

On This Page

Other indications: For conditions such as Alzheimer’s disease, anxiety, autism spectrum disorder, OCD, chronic pain, sleep disorders, heart failure, asthma, fibromyalgia, stroke-related impairment, autoimmune and musculoskeletal disorders, and other psychiatric disorders, evidence is insufficient to conclude safety and effectiveness.

Further clinical trials required before considering proven.

Drug-resistant epilepsy - TNS: Systematic review (Boon et al., 2018) found insufficient data to support TNS efficacy for drug-resistant epilepsy; additional data collection is warranted.

Evidence insufficient

Some indications and devices have limited or uncertain evidence (for example, VNS for depression, noninvasive VNS, trigeminal stimulation, and many off‑label uses). For these, the policy follows guidance recommending special governance arrangements: obtain documented shared decision‑making, explicit informed consent discussing limited evidence, and local clinical governance/ audit arrangements when use is permitted.

Use of VNS for treatment‑resistant depression should occur only with special arrangements for clinical governance, consent, and audit or research, per NICE guidance.
Noninvasive and novel device uses should be considered investigational or limited to research/programs with oversight when evidence is insufficient.

Documentation Required

Documentation Required for Prior Authorization

Clinical review of requests may require submission of complete medical records to demonstrate that each element of the coverage criteria is met. Authorization decisions may be based on the documentation submitted; incomplete records may result in denial or closure.

Include relevant history, physical examination findings, diagnostic test results (e.g., EEG, imaging), provider notes, and treatment timelines.
If the request concerns implantable VNS for epilepsy, include documentation of at least two prior adequate antiepileptic drug trials or documented intolerance.
Document shared decision‑making conversations, especially when surgery was considered and declined or deemed not an option.

Denial Risk

Documentation Insufficiency — Denial Risk

Insufficient or missing documentation that fails to demonstrate medical necessity, prior medication trials, device model/clearance, device usage/adherence, or lack of alternative surgical options may result in denial or closure of the prior authorization request.

Missing evidence of prior pharmacotherapy trials or intolerance for epilepsy cases (see Coverage Rationale) is a common cause for denial.
Omission of shared decision‑making documentation when surgery was discussed may lead to adverse coverage determinations.
Failure to supply requested medical records within review timelines may result in case closure.

Denial Risk

Noninvasive Device Exclusions

Requests for transcutaneous (non‑implantable) vagus nerve stimulation, external trigeminal nerve stimulation, or other noninvasive nerve stimulation devices for indications listed as unproven are not routinely covered. These devices are considered investigational or not medically necessary for most indications in this policy.

Transcutaneous (non‑implantable) VNS devices are listed as unproven and not medically necessary for preventing or treating the indications in this policy.
External/transcutaneous trigeminal nerve stimulation (e.g., for ADHD or migraine prevention) is generally not recommended; eTNS is not recommended for ADHD per AAP guidance.

Denial Risk

Insufficient Evidence — Denial Risk for Unsupported Indications

Several indications — including migraine, cluster headache, depression, ADHD, and many neurologic or psychiatric off‑label uses — lack sufficient high‑quality evidence. Requests for these indications are at risk for denial unless submitted as part of approved research, special governance arrangements, or with compelling supporting documentation.

Noninvasive VNS for migraine prevention/acute treatment has mixed evidence and may be denied absent strong supporting clinical documentation or governance provisions.
VNS for depression should be limited to treatment‑resistant cases and used under special arrangements per NICE; routine coverage is unlikely without trial evidence and governance documentation.
Applications for other off‑label uses listed in the Coverage Rationale are generally not medically necessary due to insufficient evidence.

Documentation Required

NICE Special Arrangements for Acute Migraine and Limited‑Evidence Uses

For acute migraine and some noninvasive suprorbital or cervical stimulation procedures, NICE and other guidance recommend use only with special arrangements for governance, consent, audit, or research. When these devices are considered, documentation of the governance arrangements and consent process should be provided.

If treating acute migraine with a device where NICE recommends special arrangements, include documentation of local governance, patient consent acknowledging limited efficacy evidence, and an audit or research plan.
Special arrangement documentation may include institutional review board (IRB) or equivalent oversight, protocol, and data collection/audit plans.

Documentation Required

Medical Record Requirements

Medical records must fully support the requested service's medical necessity. Records should be legible, maintained in the patient's chart, and made available upon request. Benefit coverage remains subject to applicable federal, state, and contract terms.

Required documentation includes comprehensive history, focused neurological examination, diagnostic testing results (EEG, imaging), treatment histories with dates and doses, and documentation of adverse effects or contraindications to prior therapies.
Benefit coverage determinations may be overridden or mandated by federal/state law or specific contract provisions; always check applicable higher‑priority requirements.

Documentation Required

Device Usage and Adherence Documentation

When evaluating noninvasive device treatments, reviewers may request evidence of device usage patterns and adherence, since efficacy in some trials was linked to adherence. Provide objective and/or contemporaneous documentation of device usage when available.

Include device usage logs, download reports, or clinician‑documented adherence assessments when available (for example, adherence thresholds used in trials such as ≥67%).
Document training/instruction provided to the patient and any adherence issues that could affect outcomes.

Documentation Required

Device Identification and Clearance Documentation

For device‑based therapies, document the specific device make/model and relevant FDA marketing authorization (510(k), PMA, PMN) or clearance information submitted with the request to assist review. Where applicable, include manufacturer labeling and indication details.

Provide the device model, manufacturer, and any available FDA product code, 510(k), PMA, or PMN reference.
If a device is being used outside of its cleared/approved indication, clearly state this and include supporting rationale and governance/consent documentation.

Documentation Required

Required Medical Record Documentation to Support Medical Necessity

The patient's record must contain complete evidence supporting medical necessity: history, physical exam, diagnostic test results, prior treatment trials (medication and surgical where applicable), shared decision‑making notes, device identification/clearance, and adherence data. Failure to present these materials may result in denial.

For epilepsy: document at least two adequate antiepileptic drug trials (or intolerance), rationale why resective surgery is not indicated or was declined, and absence of contraindications such as prior left or bilateral cervical vagotomy.
For other indications: include indication‑specific diagnostic criteria, prior therapies attempted with dates/doses, and specialist consultation notes where available.

Note

Coverage Governed by Higher‑Priority Requirements

Policy application and coverage decisions are subject to federal and state laws, and to specific contractual terms in the member's plan. When higher‑priority requirements mandate coverage or impose restrictions, those requirements supersede this policy.

Verify state‑specific provisions (this policy applies to Pennsylvania) and any plan‑level exceptions or mandates before denying coverage.
If a contractual or legal mandate requires coverage, follow that higher‑priority requirement even if the policy would otherwise limit coverage.

Prior Authorization

Medication Trials Requirement — Epilepsy

Implantable VNS for epilepsy requires failure of two or more appropriate antiepileptic medication trials (or documented intolerance). Prior pharmacotherapy is expected before considering neuromodulation except in cases with contraindications or clear clinical rationale.

Document the names, doses, durations, and outcomes of at least two antiepileptic drug trials (mono or combination) or documented intolerances.
If pharmacotherapy was not attempted due to contraindication, provide supporting clinical documentation.

Prior Authorization

Epilepsy Treatment Pathway — Prior Therapy Expectations

VNS is considered in the epilepsy treatment pathway for patients with drug‑resistant seizures after multiple medication failures and when resective surgery is not an option or is declined following shared decision making. Include documentation of placement within the treatment pathway.

Document prior antiseizure medication failures, specialist epilepsy evaluation, and the reason surgery was not pursued or was unsuccessful.
Include evidence of multidisciplinary evaluation or epilepsy center consultation when available.

Step Therapy

Prior Pharmacotherapy and Step Therapy Considerations

Neuromodulation (implantable or noninvasive) is expected to be considered after failure, intolerance, or contraindication to appropriate pharmacotherapy; step therapy requirements may exist in the clinical pathway even if not explicitly listed in this section. Reviewers will consider prior therapeutic sequencing when evaluating requests.

Although explicit step‑therapy rules are not enumerated here, provide full documentation of prior therapies in the expected sequence (medication trials, behavioral therapies, surgical evaluations) to facilitate authorization.
If the plan has specific step‑therapy programs or prior authorization pathways, follow those operational requirements in addition to this policy.

Evidence requirement

Level C requires at least one Class II study or two consistent Class III studies.

InterpretationLevel C reflects limited or conflicting evidence and usually warrants cautious interpretation when informing coverage decisions.

Transcutaneous (non-implantable) VNS (tVNS/nVNS)

DefinitionTranscutaneous (non-implantable) VNS refers to non-implantable devices that stimulate the vagus nerve through the skin (auricular or cervical approaches).

Evidence summaryThe policy states there is insufficient evidence to support the use of transcutaneous (non-implantable) VNS for many indications; larger, higher-quality studies are needed to establish safety and effectiveness.

Coverage implicationThese devices are listed as unproven/not medically necessary for preventing or treating all indications in the policy until stronger evidence emerges.

nVNS — definition and example

DefinitionNoninvasive vagus nerve stimulation (nVNS, a form of transcutaneous VNS) delivers stimulation to the cervical vagus nerve using an external device (example: gammaCore).

Clinical use examplenVNS has been studied for acute and preventive treatment of headache disorders; trials (e.g., Silberstein et al. 2016 for cluster headache; PREMIUM trial for migraine) report mixed results depending on indication and adherence.

Evidence stancePolicy notes benefit of nVNS for episodic cluster headache but inconsistent results for chronic cluster headache and mixed findings for migraine prevention (not superior in ITT in PREMIUM trial).

eTNS — definition and example

DefinitionExternal/transcutaneous trigeminal nerve stimulation (eTNS) applies stimulation to the trigeminal sensory territory (supraorbital region) using an external device (example: Cefaly).

Clinical uses studiedeTNS has been evaluated for acute and preventive migraine treatment and for other indications such as ADHD and depression in limited trials.

Evidence qualitySystematic reviews and RCTs show potential benefit for migraine and some positive early-phase trials (e.g., McGough 2019 for ADHD; Chou 2019 for acute migraine), but the overall evidence quality is low or limited and routine coverage is not established.

eTNS / external trigeminal nerve stimulation — broader definition

ScopeeTNS (external trigeminal nerve stimulation) denotes noninvasive transcutaneous stimulation of the trigeminal (supraorbital) nerve using externally applied devices, studied across migraine, ADHD, depression, and epilepsy contexts.

Examples of devicesDevices include Cefaly and other externally applied TNS systems evaluated in randomized and observational studies.

Evidence considerationsAvailable studies show potential symptom reduction in migraine and some positive signals in ADHD and depression, but heterogeneity, small sample sizes, and limited long-term data leave clinical effectiveness uncertain for many indications.

tVNS / transcutaneous vagus nerve stimulation (non-implantable)

DefinitionTranscutaneous vagus nerve stimulation (tVNS) refers to noninvasive stimulation of vagal afferents via external devices applied to auricular or cervical sites, distinct from surgically implanted VNS systems.

Regulatory noteThe policy references FDA-cleared non-implantable VNS devices and provides PMN/510(k) product-code search guidance for specific devices (product codes PKR, QAK).

Evidence summaryThe policy indicates insufficient evidence for many indications and recommends further research and cautious use, consistent with the document's overall stance on non-implantable VNS devices.

Implantable VNS — definition and approved context

DefinitionImplantable VNS refers to surgically implanted vagus nerve stimulator systems consisting of a pulse generator and lead(s) connected to the cervical vagus nerve.

Approved indicationsThe FDA has approved implantable VNS devices for indications such as epilepsy and treatment-resistant depression; the policy references product codes LYJ, MUZ, and QPY for PMA listings.

Device characteristicsImplantable systems are surgically placed and distinct from noninvasive transcutaneous devices in mechanism, regulatory pathway (PMA), and evidence base for certain indications (e.g., adjunctive therapy for drug-resistant epilepsy).

Shared Decision Making — updated note

Update summaryThe policy's definition of 'Shared Decision Making' was updated in the revision history and remains defined as a collaborative process between provider and patient considering evidence, provider experience, and patient values.

Related changesPolicy history notes updates to supporting information, clinical evidence, references, and explicit documentation expectations tied to shared decision-making and medical necessity assessments.

Documentation implicationThe policy emphasizes documenting shared decision-making discussions when relevant (e.g., when offering VNS), consistent with added medical-record requirements in the revision notes.

Added and clarified that medical records documentation may be required to assess whether the member meets clinical criteria and must fully support medical necessity (including history, physical examination, and pertinent diagnostic test results); documentation must be legible and available upon request.