Currentsierra health and lifePolicy 2026T0415GG

Gastrointestinal Motility Disorders, Diagnosis and Treatment (including Gastric Electrical Stimulation)

Defines coverage and medical necessity for diagnostic testing and treatments for gastrointestinal motility disorders (e.g., gastroparesis, constipation, anorectal disorders) for UnitedHealthcare Commercial and Individual Exchange plans.

Policy Summary

Payersierra health and life

PolicyGastrointestinal Motility Disorders, Diagnosis and Treatment

Policy CodePolicy 2026T0415GG

Change TypeNo material changes

Effective DateJan 1, 2026

Next Review DateN/A

Key ActionObtain prior authorization and document prior conservative therapy and evidence of medically refractory gastroparesis before considering gastric electrical stimulation (Enterra).

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

ProvenGES coverage stance

3 listedUnproven procedures

12Hayes GES studies

97% vs 45%VD vs MRD technical success

Shared policyTemplate update note

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Coverage Criteria for Motility Disorders and Device Therapies

Gastric Electrical Stimulation (GES) — Covered Indication

Covered when ALL of the following are met

GES coverage criteria: Gastric electrical stimulation (GES) therapy is proven and medically necessary for treating refractory gastroparesis that has failed other therapies, or chronic intractable (drug-refractory) nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology.refractory to other therapies; diabetic or idiopathic etiology

Refer to the U.S. Food and Drug Administration (FDA) section for labeling and Humanitarian Device Exemption (HDE) information

Unproven / Not Medically Necessary Procedures

The following procedures are considered unproven and not medically necessary due to insufficient evidence of efficacy:

Unproven procedures: Magnetic Resonance Imaging (MRI) Defecography for evaluating constipation and anorectal or pelvic floor disorders; Cutaneous, mucous, or serosal Electrogastrography, electroenterography, or body surface gastric mapping (e.g., Gastric Alimetry System, G-Tech Gut Tracker wireless patch system) for diagnosing intestinal or gastric disorders including gastroparesis; Esophageal Mucosal Integrity Testing by electrical impedance (e.g., MiVu Mucosal Integrity Testing System) for GERD, eosinophilic esophagitis, nonacid reflux disease, or for monitoring treatment response.

MRI Defecography Coverage Criteria

Coverage considerations for MRI defecography

When MRD is appropriate: MR defecography (MRD) may be used when anorectal manometry (ARM) and balloon expulsion test (BET) are inconclusive or when additional anatomic detail is needed for preoperative planning

Clinical practice guidelines (AGA, ACG, ASCRS) support MRD in these contexts while noting fluoroscopic defecography remains the reference standard for evacuation assessment.

Limitations to consider: MRD has variable technical success and may have lower diagnostic yield than fluoroscopic/video defecography for certain findings; do not rely solely on MRD for treatment decisions

Systematic reviews and comparative studies report lower technical diagnostic success and variable sensitivity; MRD may serve as a triage or adjunctive test.

Coverage stance summaries

Coverage and clinical stance summarized from evidence reviews and primary studies

BSGM/EGG: Electrogastrography (EGG) and body-surface gastric mapping (BSGM) detect abnormal myoelectrical findings in gastroparesis and may improve phenotyping versus gastric emptying testing, but current evidence is inadequate to establish clinical utility demonstrating improved patient outcomes; further standardized validation and clinical utility studies are required.

Systematic reviews and recent studies show physiologic signal differences and improved phenotyping but lack outcome data.

Esophageal mucosal integrity testing: Balloon mucosal impedance/impedance-based mucosal integrity testing shows potential diagnostic patterns in small studies, but evidence is limited and clinical utility to replace established diagnostics is not established; additional validation and outcome studies are needed.

Independent evidence assessments and small validation studies have not demonstrated sufficient clinical impact.

Defecography / anorectal testing: Dynamic imaging (fluoroscopic or MRI defecography) and anorectal testing (ARM, BET) are appropriate to identify structural or functional causes of outlet obstruction or defecatory disorders when clinical features suggest these conditions or when ARM and BET are equivocal.

Device-specific indication criteria

Coverage and use conditions referenced for device-based therapies and diagnostics

Entrarra HDE label conditions: Enterra is indicated for chronic, intractable (drug-refractory) nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology in patients aged 18 to 70; device should not be used in patients with gastric obstruction or pseudo-obstruction, prior gastric resection, fundoplication, eating disorders, history of seizures, primary swallowing disorders, chemical dependency, or psychogenic vomiting.

Supports coverage only within FDA HDE indications and labeling.

IRB approval requirement

Institutional oversight requirement for humanitarian devices

IRB oversight: Humanitarian use devices may only be used in facilities that have obtained institutional review board (IRB) approval to oversee the usage of the device in the facility and after an IRB has approved the use of the device to treat or diagnose the specific rare disease.

IRB approval is a precondition for facility use of HDE devices.

The policy identifies several technologies as unproven and not medically necessary because available studies do not demonstrate sufficient diagnostic accuracy, clinical utility, or impact on patient outcomes. Specifically, MRI defecography for evaluation of constipation and pelvic floor disorders, cutaneous, mucous, or serosal electrogastrography/electroenterography or body-surface gastric mapping for diagnosing gastric disorders including gastroparesis, and esophageal mucosal integrity testing by electrical impedance (e.g., MiVu) are listed as not medically necessary pending higher-quality evidence showing clinical benefit and validated diagnostic performance.

Gastric electrical stimulation (GES) is not supported as a first-line surgical therapy. Coverage is conditioned on documentation that symptoms are medically refractory after standard medical and conservative therapies have been tried. Independent evidence reviews and guideline statements note inconsistent randomized trial results and low overall quality of evidence, supporting GES use primarily for carefully selected, refractory cases rather than routine first-line implantation.

Per the FDA labeling for the Enterra Therapy System, the device is indicated under a Humanitarian Device Exemption (HDE) for chronic, drug-refractory nausea and vomiting secondary to diabetic or idiopathic gastroparesis in patients aged 18–70, and should not be used in patients with gastric obstruction or pseudo-obstruction, prior gastric resection, fundoplication, eating disorders, history of seizures, primary swallowing disorders, chemical dependency, or psychogenic vomiting.

The Enterra system’s HDE labeling requires adherence to its age and etiologic indications (diabetic or idiopathic gastroparesis, ages 18–70) and explicitly lists multiple contraindications. Facilities and clinicians must follow the FDA-specified exclusions when considering Enterra implantation to remain consistent with the approved device labeling.

The policy explicitly lists the following tests as unproven / not medically necessary: Electrogastrography (EGG) and body-surface gastric mapping / electroenterography (cutaneous, mucous, or serosal techniques) for diagnosing gastric disorders including gastroparesis; Magnetic Resonance Defecography (MRD) for evaluating constipation and anorectal or pelvic floor disorders; and Esophageal Mucosal Integrity (MI) testing by electrical impedance (e.g., MiVu) for diagnosing GERD, eosinophilic esophagitis, nonacid reflux, or for monitoring treatment response.

The evidence base for GES shows mixed quality: systematic reviews and health-technology assessments report inconsistent randomized trial findings and generally low-quality evidence. Randomized studies have not consistently confirmed benefits seen in open-label series, and authors call for additional randomized, placebo-controlled trials to determine the reliability of GES effects on symptom outcomes.

Several diagnostic procedures and device uses currently lack robust evidence of diagnostic accuracy or clinical utility. Published studies for EGG/BSGM and electrical mucosal impedance (MI) are small, heterogeneous, and of low quality; independent reviews (ECRI, Hayes) conclude that existing data do not demonstrate that these tests improve patient management or outcomes, and that further validation and clinical utility studies are needed before routine clinical use.

The Enterra Therapy System is approved only under an FDA Humanitarian Device Exemption (HDE) for a narrow indication: chronic, intractable (drug-refractory) nausea and vomiting due to diabetic or idiopathic gastroparesis in patients 18–70 years. Use of the device outside this labeled HDE indication is not supported by the FDA approval and would be considered off-label; such off-label use requires additional supporting documentation and may not be covered.

Applicable Codes and Regulatory Identifiers

Applicable CPT / Unlisted / Tracking Codesmixed

0779T	Gastrointestinal myoelectrical activity study, stomach through colon, with interpretation and report.
0868T	High-resolution gastric electrophysiology mapping with simultaneous patient-symptom profiling, with interpretation and report.
43499	Unlisted procedure, esophagus.
43647	Laparoscopy, surgical; implantation or replacement of gastric neurostimulator electrodes, antrum.
43648	Laparoscopy, surgical; revision or removal of gastric neurostimulator electrodes, antrum.
43881	Implantation or replacement of gastric neurostimulator electrodes, antrum, open.
43882	Revision or removal of gastric neurostimulator electrodes, antrum, open.
64590	Insertion or replacement of peripheral, sacral, or gastric neurostimulator pulse generator or receiver, requiring pocket creation and connection between electrode array and pulse generator or receiver.
64595	Revision or removal of peripheral, sacral, or gastric neurostimulator pulse generator or receiver, with detachable connection to electrode array.
72195	Magnetic resonance (e.g., proton) imaging, pelvis; without contrast material(s).

1–10 of 15

1/2

Regulatory product codes mentionedmixed

MYE / FFX

FDA product codes referenced for gastric electrical mapping and radiopaque markers

FDA product codes and device identifiers mentionedmixed

MYE	FDA product code referenced for cutaneous electrogastrography, electroenterography, and body surface gastric mapping
FFX	FDA product code referenced for certain motility testing devices and radiopaque markers
QIS	FDA product code for MiVu Mucosal Integrity Testing System

Provider Requirements, Prior Authorization, and Documentation

Prior Authorization

Prior Authorization Required

Prior authorization is required for neurostimulator procedures, including gastric electrical stimulation (GES) with the Enterra system and other implantable neurostimulator devices. Obtain prior authorization before scheduling implantation or replacement procedures.

Affected services: GES implantation, pulse generator replacement, device revisions and removals where neurostimulator coding applies

Documentation Required

Documentation May Be Required

Medical records documentation may be requested to confirm the member meets coverage criteria. Lack of necessary documentation may result in denial or delay of the request. Providers should be prepared to submit operative reports, prior conservative therapy records, medication trials, diagnostic testing results, and specialist evaluations.

Examples: symptom history, treatment timeline, medication trials and responses, prior test results (e.g., gastric emptying study), consult notes

Clinical Background and Context

Gastroparesis commonly presents with nausea, vomiting, early satiety, bloating, and epigastric pain. Diagnosis requires objective evidence of delayed gastric emptying, with gastric scintigraphy recognized as the reference standard. Clinical evaluation aims to exclude mechanical obstruction and to document symptom severity and response to medical therapies when considering advanced interventions such as gastric electrical stimulation.

Definitions and Device Descriptions

Gastroparesis definition

DefinitionGastroparesis: a digestive disorder in which the motility of the stomach is either abnormal or absent (delayed gastric emptying).

Typical symptomsNausea, vomiting, early satiety, bloating, and epigastric pain (clinical context for diagnosis).

Diagnostic implicationDiagnosis requires objective evidence of delayed gastric emptying; scintigraphy is the reference standard (see diagnostic sections).

Electrogastrography (EGG) definition

DefinitionElectrogastrography (EGG): a non-invasive method for the measurement of gastric myoelectrical activity using cutaneous electrodes placed on the abdominal skin over the stomach.

OutputSurface recording called the electrogastrogram used to identify gastric dysrhythmia, abnormal slow-wave propagation, and electro-mechanical uncoupling.

Policy Summary

Payersierra health and life

PolicyGastrointestinal Motility Disorders, Diagnosis and Treatment

Policy CodePolicy 2026T0415GG

Change TypeNo material changes

Effective DateJan 1, 2026

Next Review DateN/A

Key ActionObtain prior authorization and document prior conservative therapy and evidence of medically refractory gastroparesis before considering gastric electrical stimulation (Enterra).

SourceLink

On This Page

Guidelines advise use of defecography for inconclusive anorectal testing and preoperative planning, recognizing modality-specific strengths and limitations.

Gastric electrical stimulation (Enterra): Enterra therapy is an FDA Humanitarian Device Exemption (HDE)-approved option for chronic, drug-refractory nausea and vomiting secondary to diabetic or idiopathic gastroparesis in patients aged 18–70; use must follow labeled indications and facility IRB approval for HDE use.

Coverage limited to FDA HDE indication and appropriate institutional oversight.

Denial Risk

Insufficient/Incomplete Evidence May Lead to Denial

Requests lacking sufficient evidence that the proposed test or therapy is supported by peer-reviewed clinical data may be denied. When the literature is limited or inconsistent for a given technology (e.g., certain BSGM/EGG devices or novel impedance systems), prior authorization reviewers may determine the service is investigational or not medically necessary.

Technologies at risk for denial: electrogastrography/electroenterography/BSGM for routine diagnosis, esophageal mucosal integrity testing as a sole diagnostic tool

Denial Risk

Device Labeling, Indications, and Contraindications

Some devices (including those marketed under a Humanitarian Device Exemption, HDE) have specific labeling, indications, and contraindications. Use of a device outside of its labeled indications or in populations excluded by the label (for example, Enterra HDE exclusions) may result in noncoverage or denial.

Enterra HDE exclusions include: gastric obstruction or pseudo-obstruction, prior gastric resection, fundoplication, eating disorders, history of seizures, primary swallowing disorders, chemical dependency, psychogenic vomiting

Documentation Required

IRB Approval and Documentation Required for HDE Devices

Humanitarian Use Devices (HDE) require institutional oversight. Facilities must have IRB approval for use of HDE-labeled devices and documentation that the IRB approved treating the specific condition with the device. Prior authorization submission should include evidence of IRB approval when applicable.

IRB documentation: institutional approval letter or IRB protocol reference and confirmation that the HDE use was approved for the patient or program

Prior Authorization

Refractory Requirement and Therapy Sequencing for GES

GES (Enterra) is considered for medically refractory gastroparesis: patients must be refractory to standard/conservative therapies before GES is considered. Document failure of dietary measures, prokinetic and antiemetic medication trials, and other standard treatments.

Documented trials and lack of adequate response to: dietary modification, prokinetic agents, antiemetics; documentation that patient is not taking opioids if relevant

Step Therapy

Conservative Therapy Required Prior to Advanced Testing or Device Therapies

Conservative therapy should be attempted and documented before pursuing advanced diagnostic testing or device therapies. Prior authorization reviewers expect evidence that less invasive management was tried and failed when appropriate.

Conservative measures: dietary changes, fiber/laxatives for constipation evaluations, behavioral therapy, medication adjustments as clinically indicated

Related techniquesElectroenterography (intestinal recordings) and body-surface gastric mapping (high-resolution electrode arrays with analytics) are similar procedures for myoelectrical assessment.

Magnetic Resonance Defecography definition

DefinitionMagnetic Resonance Defecography: a noninvasive MRI-based test that obtains images at various stages of defecation to evaluate pelvic floor anatomy, dynamic motion, and rectal evacuation simultaneously.

Clinical useUsed to assess defecatory disorders and pelvic floor dysfunction when dynamic anatomic detail is needed or when anorectal testing is inconclusive.

Advantages/limitationsOffers superior soft-tissue resolution and no radiation versus fluoroscopic defecography, but may have variable technical success and lower diagnostic yield for some findings; fluoroscopic defecography in the seated position remains the evacuation reference with high construct validity.

Gastric electrical stimulation (GES) definition

DefinitionGastric electrical stimulation (GES): implantable electrical stimulation of the stomach (for example, the Enterra system) intended to reduce symptoms of refractory gastroparesis, particularly chronic, drug-refractory nausea and vomiting.

Indication contextGuidelines (ACG, AGA) suggest considering GES for medically refractory diabetic or idiopathic gastroparesis after standard therapy failure; evidence quality is low to moderate and recommendations are conditional.

Device statusIn the U.S., the Enterra Therapy System is the only marketed GES device and is approved under an FDA Humanitarian Device Exemption for chronic, intractable nausea and vomiting secondary to diabetic or idiopathic gastroparesis in patients aged 18–70.

MRI defecography (MRD) definition

DefinitionMRI defecography (MRD): dynamic MRI-based imaging of defecation used to assess pelvic floor anatomy and function during simulated evacuation.

Appropriate useMay be used when anorectal manometry and balloon expulsion test are inconclusive or when additional anatomic detail is needed for preoperative planning, per guideline guidance.

Performance noteMRD sensitivity is higher when performed with an evacuation phase; overall evidence is insufficient to show MRD is superior to conventional defecography for all findings.

Defecography (fluoroscopic/MRI) definition

DefinitionDefecography (fluoroscopic/MRI): dynamic imaging tests performed during evacuation to evaluate pelvic floor structure and function and identify causes of outlet obstruction or defecatory disorders.

Modality differencesFluoroscopic (video) defecography performed in the seated position has strong construct validity for evacuation assessment; MRI offers better soft-tissue resolution and no radiation but may be performed supine.

Clinical roleUsed to identify structural defects (rectocele, enterocele, intussusception) and functional disorders when clinical features suggest DD or when anorectal testing is equivocal.

Humanitarian Device Exemption (HDE) Enterra definition

DefinitionHumanitarian Device Exemption (HDE) Enterra: the Enterra gastric electrical stimulation system approved by the FDA under a Humanitarian Device Exemption for treatment of chronic, intractable (drug-refractory) nausea and vomiting secondary to diabetic or idiopathic gastroparesis in patients aged 18–70.

Regulatory implicationHDE approval denotes a narrow humanitarian indication; use must follow labeled indications and facility-level oversight per regulatory guidance.

Clinical cautionEvidence and guideline statements describe GES/Enterra as an option for medically refractory cases and recommend patient selection consistent with the HDE labeling.

Enterra Therapy System definition

DefinitionEnterra Therapy System: an FDA Humanitarian Device Exemption gastric electrical stimulation system indicated for chronic, intractable (drug-refractory) nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology in patients aged 18 to 70.

Label contraindicationsPer FDA labeling, Enterra should not be used in patients with gastric obstruction or pseudo-obstruction, prior gastric resection, fundoplication, eating disorders, history of seizures, primary swallowing disorders, chemical dependency, or psychogenic vomiting.

Clinical guidanceClinical society guidance (ACG, AGA) conditionally supports considering Enterra for refractory patients after failure of standard therapies; selection should consider underlying etiology (diabetic or postsurgical may have greater benefit).

MiVu Mucosal Integrity Testing System (MiVu/QIS) definition

DefinitionMiVu Mucosal Integrity Testing System (MiVu/QIS): an FDA-cleared Class II device intended to assess esophageal mucosal integrity as an adjunct to endoscopy to help differentiate GERD, eosinophilic esophagitis, and non-GERD conditions.

Regulatory statusReceived FDA de novo clearance as a Class II device (de novo 12/23/2019) with subsequent 510(k) activity (K230056 referenced).

Evidence noteClinical evidence is limited; independent assessments (ECRI, Hayes) and available studies do not establish sufficient clinical utility for routine replacement of established diagnostics (pH monitoring/biopsy) per policy review.