Deep Brain and Cortical Stimulation (for New Mexico Only)

Coverage Summary

This is the state-specific (New Mexico) UnitedHealthcare medical policy CS030NM.C on Deep Brain Stimulation (DBS) and Responsive Cortical Stimulation (RNS). The policy identifies proven/medically necessary indications for DBS: dystonia, essential tremor, Parkinson disease, and refractory epilepsy for a partial or focal seizure disorder, and for responsive cortical stimulation: refractory partial or focal seizure disorder.

The policy specifies unproven and not medically necessary uses: DBS and/or cortical stimulation for obsessive-compulsive disorder (OCD) and for all other indications not listed as proven and medically necessary, and responsive cortical stimulation for all other indications (not partial/focal seizure disorder).

Required documentation to support medical necessity includes relevant medical history, physical examination, and results of pertinent diagnostic tests or procedures; records must be legible, maintained in the patient’s medical record, and made available upon request. Benefit coverage is determined by federal, state, or contractual requirements and applicable laws; documentation may be requested to assess criteria but does not guarantee coverage.

Referenced procedure and supply codes are listed for provider reference and include CPT codes such as 61850, 61860, 61863, 61864, 61867, 61868, 61885, 61886, 61889, 61891, 64999 and HCPCS/L-codes such as L8679, L8680, L8682, L8685, L8686, L8687, L8688 (listing does not imply coverage or payment entitlement).

For detailed clinical coverage criteria and prior authorization assessment, the policy delegates medical necessity determinations to InterQual® CP: Procedures, Stereotactic Introduction, Subcortical or Cortical Electrodes.

Policy effective date and review: Effective: April 1, 2026; Last review: April 1, 2026 (policy history notes material changes and updated clinical evidence; prior version CS030NM.B archived).

At-a-glance

Proven/medically necessary indications4

RNS proven indication1

Not medically necessary: OCD1

Major referenced CPT/HCPCS codes listed10

Medical-Necessity Criteria

Medically Necessary / Proven Indications

Deep brain stimulation is proven and medically necessary for treating the following indications:

ANY of the following

Dystonia
Essential tremor
Parkinson disease
Refractory epilepsy for a partial or focal seizure disorder

Responsive cortical stimulation

Coding

Referenced CPT (procedure) codesCPT

61850	Twist drill or burr hole(s) for implantation of neurostimulator electrodes, cortical.
61860	Craniectomy or craniotomy for implantation of neurostimulator electrodes, cerebral, cortical.
61863	Twist drill, burr hole, craniotomy, or craniectomy with stereotactic implantation of neurostimulator electrode array in subcortical site; first array.
61864	Twist drill, burr hole, craniotomy, or craniectomy with stereotactic implantation of neurostimulator electrode array in subcortical site; each additional array.
61867	Twist drill, burr hole, craniotomy, or craniectomy with stereotactic implantation of neurostimulator electrode array in subcortical site with intraoperative microelectrode recording; first array.
61868	Twist drill, burr hole, craniotomy, or craniectomy with stereotactic implantation of neurostimulator electrode array in subcortical site with intraoperative microelectrode recording; each additional array.
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.
61889	Insertion of skull-mounted cranial neurostimulator pulse generator or receiver, including craniectomy or craniotomy, when performed, with direct or inductive coupling, with connection to depth and/or cortical strip electrode array(s).
61891	Revision or replacement of skull-mounted cranial neurostimulator pulse generator or receiver with connection to depth and/or cortical strip electrode array(s).

1–10 of 11

1/2

Referenced HCPCS / Supply (L-codes)HCPCS

L8679	Implantable neurostimulator, pulse generator, any type.
L8680	Implantable neurostimulator electrode, each.
L8682	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.

Provider Actions

Documentation Required

Maintain medical record documentation to support medical necessity

Document relevant medical history, physical examination findings, and results of pertinent diagnostic tests or procedures that fully support the medical necessity of the requested deep brain stimulation or responsive cortical stimulation service. Ensure the documentation is legible, maintained in the patient’s medical record, and made available upon request. Note that benefit coverage is determined by federal, state, or contractual requirements and applicable laws; documentation may be required to assess whether a member meets clinical criteria but does not guarantee coverage.

Relevant medical history
Physical examination
Results of pertinent diagnostic tests or procedures
Documentation must be legible
Documentation must be maintained in the patient’s medical record and made available upon request

Background

Deep Brain Stimulation (DBS) implants electrodes surgically into selected brain areas (examples: internal globus pallidus [GPi], subthalamic nucleus [STN], ventral intermediate nucleus [VIM] of the thalamus) and delivers electrical pulses from an implanted pulse generator to interrupt pathways responsible for abnormal movement or seizures. The therapy is reversible and adjustable, and typical system components include an implantable pulse generator (neurostimulator), implantable lead with electrodes, subcutaneous extension wires, and connecting hardware.

Responsive Cortical Stimulation (RNS) is a closed-loop implantable neurostimulator system designed to detect abnormal electrical brain signals that precede seizures and deliver stimulation in response to normalize activity and prevent seizures. The RNS System example places a neurostimulator in the skull with leads in seizure-originating areas and is intended to provide seizure prevention, reduced adverse events compared with some other neurostimulation methods, and home-to-clinic data transmission.

Applicable procedure codes for implantation and related procedures include cortical and subcortical electrode placement and pulse generator insertion/revision (examples: CPT 61850, 61860, 61863–61868, 61885, 61886, 61889, 61891, 64999) and supply codes for implantable neurostimulator components (examples: HCPCS L8679, L8680, L8682, L8685–L8688).

Evidence and References

Clinical evidence and evaluation are summarized in the policy and delegated InterQual criteria are used for medical necessity determinations. The policy notes multiple systematic reviews, meta-analyses, randomized controlled trials, and recent literature assessing DBS and closed-loop stimulation approaches across movement, seizure, and psychiatric indications.

Specifically for obsessive-compulsive disorder (OCD), the policy and supporting references summarize several systematic reviews and sham-controlled trials showing some symptom reduction with DBS but characterize the overall evidence as low quality or insufficient for routine coverage. Multiple reviews and trials report promising results in selected, treatment-resistant populations but cite small sample sizes, methodological heterogeneity, and safety considerations (including device-related complications and psychiatric adverse events), meaning further high-quality studies are needed.

The policy history records material changes: added language clarifying DBS and cortical stimulation are unproven and not medically necessary for OCD and all other indications not listed as proven, clarified medical record documentation requirements, updated Clinical Evidence and References, and archived the prior policy version (CS030NM.B).

Revision History

04/01/2026policy_changeLatest

Added language clarifying deep brain stimulation and/or cortical stimulation are unproven and not medically necessary for treating obsessive‑compulsive disorder (OCD) and all other indications not listed as proven and medically necessary.

04/01/2026documentation_requirement_updateLatest

Revised medical records documentation requirements to state benefit coverage is determined by federal, state, or contractual requirements and that documentation may be required to assess clinical criteria; records must contain relevant medical history, physical examination, and results of pertinent diagnostic tests or procedures, be legible, maintained in the patient’s medical record, and made available upon request.