Modifiedsierra health and lifePolicy 2026T0415HH

Gastrointestinal Disorders Diagnostic Procedures

This policy governs coverage and medical necessity determinations for several diagnostic procedures used in gastrointestinal disorders (e.g., MRI defecography, electrogastrography, body surface gastric mapping, esophageal mucosal integrity testing, and functional lumen imaging probe/EndoFLIP) for UnitedHealthcare Commercial and Individual Exchange plans.

Policy Summary

Payersierra health and life

PolicyGastrointestinal Disorders Diagnostic Procedures

Policy CodePolicy 2026T0415HH

Change TypeTitle changeadded and removed listed proceduresCPT code removals

Effective DateFeb 1, 2026

Next Review DateN/A

Key ActionObtain prior authorization and document prior standard testing and clinical rationale when ordering FLIP, MRI defecography, or BSGM.

SourceLink

POLICY UPDATE CHANGES

Title changed from 'Gastrointestinal Motility Disorders, Diagnosis and Treatment' to updated title and coverage rationale moved for gastric electrical stimulation to a separate medical policy.

Added 'Functional Lumen Imaging Probe (FLIP) technology for diagnosing Achalasia' to the list of unproven and not medically necessary procedures.

Removed examples of body surface gastric mapping systems (e.g., Gastric Alimetry System, G-Tech Gut Tracker) from the list of unproven and not medically necessary procedures.

Removed several CPT codes (43647, 43648, 43881, 43882, 64590, 64595) from the Applicable Codes section.

5unproven procedures listed

~16%constipation prevalence (adults)

33%

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constipation prevalence (60+)

0.96BSGM accuracy (patient-level)

Coverage Criteria and Clinical Guidance

Not medically necessary / Unproven 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 for diagnosing intestinal or gastric disorders including Gastroparesis; Esophageal Mucosal Integrity Testing by electrical impedance for diagnosis of GERD, eosinophilic esophagitis (EoE), and nonacid reflux disease, or for monitoring treatment response in GERD and EoE; Functional Lumen Imaging Probe (FLIP) technology for diagnosing Achalasia.

Listed explicitly in coverage rationale as not medically necessary.

Gastroparesis diagnostic criteria

Diagnostic standard and expectations for gastroparesis:

Gastroparesis diagnostic standard: The diagnosis of gastroparesis requires objective evidence of clearly delayed gastric emptying in symptomatic patients; scintigraphy is the reference standard and requires adherence to validated standardized meal protocols and adequate imaging duration.

Clinical utility depends on complete consumption of adequate test meals and adequate duration of imaging; adhere to validated protocols.

FLIP (EndoFLIP) — complementary diagnostic criteria

FLIP/EndoFLIP use considerations

FLIP complementary use: FLIP (EndoFLIP) is an FDA‑cleared measurement tool that may be used as a complementary assessment of esophagogastric junction opening dynamics and esophageal wall stiffness; it should not be used alone to make a diagnosis or direct treatment decisions.

Document DI and CSA measurements (commonly obtained at 30 mL and 40 mL distension) and perform FLIP in the context of concurrent endoscopy or manometry when possible; follow AGA best‑practice recommendations and standardized protocols.

MRI defecography — diagnostic role and limitations

MRI defecography use considerations

Indications for MRD: MR defecography may be used when anorectal manometry (ARM) and balloon expulsion test (BET) are inconclusive, for preoperative anatomical assessment, or when superior soft‑tissue resolution is required; consider evacuation‑phase imaging to improve sensitivity.

Fluoroscopic evacuation proctography (EP) / defecography is the reference standard for many posterior pelvic floor disorders; MRD technical success and diagnostic yield are variable and MRD is not demonstrated superior to conventional defecography in available evidence.

EGG/BSGM — diagnostic role and evidence

EGG/BSGM use considerations

BSGM/EGG evaluation context: EGG and Body Surface Gastric Mapping (BSGM) may be used to phenotype gastric myoelectrical activity in patients with gastroparesis, chronic nausea/vomiting syndromes, or post‑fundoplication symptoms after completion of standard work‑up (including endoscopy and gastric emptying testing) and using standardized recording protocols.

Although BSGM shows improved phenotyping versus traditional EGG, clinical utility for improving patient outcomes remains unproven and these methods should follow validated protocols and be applied after standard testing.

BSGM vs EGG evidence

Evidence summary distinguishing BSGM/EGG performance

BSGM performance: Observational studies report that BSGM provides substantially tighter frequency ranges, more symptom correlations, and higher patient‑level classification accuracy compared with traditional EGG (e.g., higher accuracy versus controls and blinded consensus panels), but evidence is limited to observational cohorts and retrospective studies.

Supports that BSGM may outperform low‑resolution EGG for detecting gastric myoelectrical abnormalities, but clinical‑utility studies demonstrating improved outcomes are lacking.

Mucosal impedance testing

Esophageal mucosal integrity testing evidence and limitations

MI testing validation: Small prospective and retrospective studies report distinct mucosal impedance (MI) patterns among GERD, EoE, and non‑GERD populations and initial validation suggests MI can distinguish these conditions; however, published studies are limited by small sample sizes, lack of blinding, homogeneous cohorts, and need independent validation.

Clinical utility (impact on diagnosis, management, and patient outcomes) has not been established; device reviews (ECRI, Hayes) state MI systems are not to be used as sole diagnostic screening tools and additional larger validation and clinical‑utility studies are required.

The policy identifies a set of diagnostic procedures as unproven and not medically necessary because current evidence does not demonstrate adequate efficacy or clinical utility. Specifically, the policy lists MRI defecography for evaluation of constipation and anorectal or pelvic floor disorders, cutaneous, mucous, or serosal electrogastrography/electroenterography/body surface gastric mapping for intestinal or gastric disorders including gastroparesis, esophageal mucosal integrity testing by electrical impedance for diagnosis or monitoring of GERD, eosinophilic esophagitis (EoE), and nonacid reflux, and Functional Lumen Imaging Probe (FLIP) technology for diagnosing achalasia as not medically necessary due to insufficient evidence of efficacy.

FLIP (EndoFLIP) may be used as a complementary tool to assess esophagogastric junction opening dynamics and lumen distensibility in patients who cannot complete or tolerate standard manometry, but clinicians should not make a diagnosis or treatment decision based on FLIP assessment alone. Similarly, body surface gastric mapping or transcutaneous electrogastrography (BSGM/EGG) currently lack sufficient, high-quality evidence to replace standard gastric emptying testing; these technologies may be considered investigational or adjunctive pending standardized protocols and further validation.

Esophageal mucosal integrity (MI) testing by electrical impedance is still evolving and is not sufficiently developed to substitute for standard diagnostic methods such as endoscopy with biopsy or physiologic testing. Published reviews and device assessments note limited, low-quality studies and conclude the technology is not intended for use as a sole diagnostic screening tool; additional clinical validity and clinical utility data are required before it can replace established methods.

An operational change in this policy relocates coverage language for gastric electrical stimulation (GES) therapy to a separate Medical Policy titled 'Minimally Invasive Procedures for the Treatment of Upper Gastrointestinal Diseases.' The current policy has removed and relocated GES-related text accordingly; providers should refer to the referenced Medical Policy for coverage determinations related to GES.

MRI defecography (MRD) may be used selectively—for example, when anorectal manometry (ARM) and balloon expulsion testing (BET) are inconclusive, for detailed preoperative anatomic assessment, or when soft-tissue resolution is needed. However, MRD has variable technical success and is not established as superior to conventional fluoroscopic defecography/evacuation proctography, so its use should be reserved for cases where standard testing is inadequate or additional information is required.

Existing evidence does not show that MRI defecography is superior to conventional defecography; some studies report comparable or inferior performance. Therefore, MRD should not be considered a routine replacement for conventional evacuation proctography or fluoroscopic defecography when those standard studies are available and clinically appropriate.

Clinical studies of mucosal impedance (MI) testing are limited in size and quality and have not established that MI testing is safe and effective for diagnosing GERD, EoE, or nonacid reflux, nor for reliably monitoring treatment response. Consequently, MI testing is considered investigational and insufficient as a standalone diagnostic or monitoring tool pending larger validation and clinical utility studies.

Policy revision explicitly added Functional Lumen Imaging Probe (FLIP) technology for diagnosing achalasia to the list of unproven and not medically necessary procedures. While FLIP (EndoFLIP) is FDA-cleared as an adjunctive measurement tool and may inform management in specialized centers, the evidence does not support its use as a standalone diagnostic test for achalasia.

The policy update removed specific examples of body surface gastric mapping and electrogastrography devices (formerly listed examples such as the Gastric Alimetry System and G‑Tech Gut Tracker) from the unproven list. This change reflects removal of example device names from the policy language rather than endorsement of clinical utility; the category of cutaneous/mucous/serosal EGG, electroenterography, or BSGM remains addressed as lacking sufficient evidence.

Applicable Procedure and Device Codes

Referenced procedure codesCPT

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.
72195	Magnetic resonance (e.g., proton) imaging, pelvis; without contrast material(s).
72196	Magnetic resonance (e.g., proton) imaging, pelvis; with contrast material(s).
72197	Magnetic resonance (e.g., proton) imaging, pelvis; without contrast material(s), followed by contrast material(s) and further sequences.
76498	Unlisted magnetic resonance procedure (e.g., diagnostic, interventional).
91132	Electrogastrography, diagnostic, transcutaneous.
91133	Electrogastrography, diagnostic, transcutaneous; with provocative testing.

Referenced procedures (billing codes not specified)mixed

No specific CPT codes listed

Documented procedures (EndoFLIP/FLIP, MRI defecography, BSGM) referenced without explicit billing codes in this section.

Device / FDA product and 510(k) referencesmixed

MYE or FFX	FDA product codes referenced for cutaneous electrogastrography and related devices
QIS	FDA product code referenced for MiVu Mucosal Integrity Testing System
K170833	FDA 510(k) ID for EndoFLIP System
K230056	FDA 510(k) Premarket Notification number for MiVu (April 25, 2023)

Previously listed CPT codes removedCPT

43647	CPT code removed from Applicable Codes
43648	CPT code removed from Applicable Codes
43881	CPT code removed from Applicable Codes
43882	CPT code removed from Applicable Codes
64590	CPT code removed from Applicable Codes
64595	CPT code removed from Applicable Codes

inv-21: Gastric emptying reference standard — meal protocol and imaging duration expectations

Reference standardGastric emptying scintigraphy is the reference standard for measurement of gastric emptying; adherence to validated standardized meal protocols and adequate imaging duration is required.

Meal consumptionClinical utility depends on complete consumption of the adequate test meal prior to imaging.

Protocol adherenceAll gastrointestinal function tests require adherence to adequately validated, standardized study protocols for recording and interpretation.

inv-22: EndoFLIP volumetric distension volumes — customary measurement volumes (30 mL and 40 mL)

Measurement volumesEndoFLIP DI and CSA measurements are performed during volumetric distension at both 30 mL and 40 mL saline fill volumes.

Prior Authorization, Documentation, and Operational Guidance

Prior Authorization

Prior authorization and referenced procedure codes

Prior authorization may be required for some of the procedures and devices referenced in this policy. Inclusion of a code in the Applicable Codes list is for reference only and does not guarantee coverage or payment. Providers should verify prior authorization requirements with Sierra Health and Life and confirm member-specific benefit plan coverage before scheduling services.

Some listed CPT/HCPCS codes may require prior authorization and may be denied if the procedure is considered unproven or documentation is insufficient.
Providers must reference the member-specific benefit plan document for coverage determinations.

Prior Authorization

Prior authorization for adjunctive diagnostic devices

Adjunctive diagnostic devices that have FDA clearance (e.g., EndoFLIP, MiVu, gastric mapping devices) may still require prior authorization and clinical documentation to support medical necessity. FDA clearance alone is not a basis for coverage.

Devices cleared via 510(k) or de novo pathways (EndoFLIP, MiVu, certain gastric mapping systems) are regulated by FDA but are subject to payer medical necessity review.

Clinical Background and Epidemiology

Constipation, fecal incontinence, and gastroparesis are common conditions that often require objective testing to clarify underlying pathophysiology and guide management. Population estimates show constipation affects approximately 16% of adults and up to 33% of adults over age 60. For gastroparesis specifically, a diagnosis requires objective evidence of delayed gastric emptying, with radionuclide gastric emptying scintigraphy regarded as the reference standard when performed with validated meal protocols and adequate imaging duration.

Terms and Definitions

inv-44: Achalasia — definition

DefinitionAchalasia: a primary esophageal motor disorder characterized by degeneration of the myenteric plexus leading to impaired relaxation of the esophagogastric junction and loss of organized peristalsis in the esophageal body.

Source attributionDefinition cites American Society of Gastrointestinal Endoscopy (ASGE) description.

Clinical implicationAchalasia is included as a defined term added in the revised policy definitions.

inv-45: Constipation — definition

DefinitionConstipation: infrequent or hard-to-pass bowel movements, hard stools, or sensation of incomplete evacuation; infrequent defined as fewer than three bowel movements per week.

Symptoms includedMay include hard stools and incomplete bowel movement sensation in addition to low frequency.

Policy Revision History and Material Changes

2026-02-01title_changeLatest

Policy title changed from 'Gastrointestinal Motility Disorders, Diagnosis and Treatment' to an updated title; coverage rationale for gastric electrical stimulation (GES) was removed and relocated to a separate policy.

2026-02-01added_unproven_procedure

Functional Lumen Imaging Probe (FLIP) technology for diagnosing achalasia was added to the list of unproven and not medically necessary procedures.

2026-02-01

Policy Summary

Payersierra health and life

PolicyGastrointestinal Disorders Diagnostic Procedures

Policy CodePolicy 2026T0415HH

Change TypeTitle changeadded and removed listed proceduresCPT code removals

Effective DateFeb 1, 2026

Next Review DateN/A

Key ActionObtain prior authorization and document prior standard testing and clinical rationale when ordering FLIP, MRI defecography, or BSGM.

SourceLink

On This Page

Repeated measuresDI and CSA were measured twice during volumetric distension at each volume (30 mL and 40 mL) to obtain assessments at the narrowest EGJ site.

Context of useFLIP is used during endoscopy and measurements should be documented in conjunction with EGD/manometry when possible.

inv-23: MRI defecography diagnostic parameter — anorectal angle change threshold noted in a study

Reported diagnostic thresholdIn one retrospective single-center study, an anorectal angle (ARA) change of less than 1.5 degrees was reported as a finding associated with dyssynergic defecation.

Study limitationsFindings were from a single-center, retrospective study with small sample size and require independent validation.

Parameter assessmentARA change was one of nine MR defecography parameters analyzed (rest, defecation, and change between phases) and contributed to diagnostic performance alongside M-line and puborectalis findings.

Prior authorization should be requested when using adjunctive diagnostic devices as part of the evaluation of gastrointestinal motility or mucosal integrity.

Documentation should clearly state how the device result will change patient management beyond established standard testing.

Prior Authorization

Code applicability and prior authorization

Codes shown in the Applicable Codes section are illustrative and some CPT codes previously listed in earlier versions have been removed. Providers must verify prior authorization and coverage for the specific code and service submitted.

Listing of a code does not imply that the service is covered, reimbursable, or will be paid.
Previously removed CPT codes (per policy history) should not be assumed covered — check member benefits and prior authorization requirements.

Denial Risk

FLIP complementary use expectation

FLIP (EndoFLIP) is an adjunctive measurement tool and should not be used alone to make a diagnosis or a definitive treatment decision. Requests relying solely on FLIP results without corroborating conventional diagnostic testing carry a risk of denial.

EndoFLIP is intended as a complementary tool to assess esophagogastric junction dynamics and wall stiffness.
Clinical decisions should be based on the totality of clinical evaluation and conventional testing (e.g., manometry, endoscopy) rather than FLIP alone.

Denial Risk

Insufficient evidence — potential denial

Procedures and tests identified as unproven or lacking convincing evidence (for example: MRI defecography as a replacement for evacuation proctography, electrogastrography/BSGM, and esophageal mucosal integrity testing used as sole diagnostic/monitoring tools) may be denied if requested without adequate supporting documentation or when used as the only basis for diagnosis or management.

MRI defecography is not a replacement for evacuation proctography (EP) and may be considered unproven for some indications when compared to conventional reference tests.
EGG, electroenterography, and BSGM lack sufficient evidence of clinical utility and may be denied if submitted as the primary diagnostic test for gastroparesis without standard testing.
Mucosal impedance testing lacks sufficient evidence to support use as the sole diagnostic or monitoring modality for GERD or EoE.

Documentation Required

Documentation expectations

Documentation submitted with prior authorization requests should clearly demonstrate the clinical indication, prior evaluations and results, physical examination findings (including DRE when relevant), and how the requested test will alter management. Reference to member-specific benefit plan language is required to determine coverage.

Include clinical indication and relevant history (symptoms, duration, prior therapies).
Include prior diagnostic testing results (e.g., ARM, BET, manometry, scintigraphy, endoscopy, pH testing) and dates.
Document relevant physical exam findings (e.g., digital rectal exam for defecatory disorders) and rationale for advanced testing.
Reference the member-specific benefit plan document when asserting coverage.

Documentation Required

FLIP documentation

When FLIP is requested, document the procedural context, protocol, and how FLIP measurements (e.g., distensibility index [DI], cross-sectional area [CSA]) were obtained and will be used. If manometry is not performed contemporaneously, provide rationale.

State whether FLIP was performed during endoscopy (EGD) or as a separate procedure and include timing.
Report measured DI and CSA values, balloon volumes used (e.g., 30 mL, 40 mL), and the clinical interpretation tied to management decisions.
If esophageal manometry was not performed, explain why and how management decisions will be supported without it.

Documentation Required

MRD documentation

For MRI defecography (MRD) authorization requests, provide the indication, prior conventional testing results (ARM, BET, evacuation proctography when available), and specify the imaging technique used (including whether an evacuation phase was performed). MRD should generally be considered after or alongside conventional testing unless clinically justified.

Document prior anorectal testing and whether results were inconclusive, contraindicated, or insufficient for clinical decision-making.
Specify MRD protocol details: static and dynamic sequences, whether evacuation phase was included, patient positioning, and contrast/gel technique.
Note that MRD has variable technical success and is not a substitute for evacuation proctography (EP) when EP is the reference standard.

Documentation Required

BSGM/EGG documentation

For BSGM/EGG requests, include prior work-up demonstrating need (e.g., endoscopy, gastric emptying study), adherence to standardized test protocols (fasting, medication hold, test meal details), and recording/analysis parameters. BSGM/EGG is investigational for routine diagnosis until stronger evidence of clinical utility is available.

Provide evidence of prior standard testing such as scintigraphic gastric emptying testing and how BSGM will complement or change management.
Document pre-test preparation: fasting duration, medication holds, test meal composition, and duration of recording.
Include device/method details, spectral analysis parameters, and how results will be interpreted relative to management plans.

Documentation Required

Documentation supporting mucosal impedance testing

When mucosal impedance (MI) testing is used, submit documentation linking MI findings to endoscopy, pH testing, and pathology as applicable. MI is considered adjunctive; relying on MI alone for diagnosis or monitoring increases the likelihood of denial.

Include EGD findings and biopsy/pathology when asserting MI-based diagnoses (GERD, EoE).
Provide pH/pH-impedance study results when available and explain how MI adds incremental diagnostic value.
If MI is being used to avoid other standard tests, provide evidence-based rationale and describe how management will change based on MI results.

Note

Documentation and member-specific plan note

Always cross-check requests against the member-specific benefit plan; this policy is informational and the member’s benefit document controls. In case of conflict, the member-specific plan governs. Prior authorization decisions and coverage determinations must reference both this policy and the member’s plan language.

The member-specific benefit plan document may contain coverage limits or exclusions that differ from this policy.
When submitting prior authorization, cite the member’s plan and include all required clinical documentation to support medical necessity.

Step Therapy

Preferred testing pathway for gastroparesis

For suspected gastroparesis, prefer standard testing (scintigraphic gastric emptying study) as the reference standard and ensure adherence to validated protocols (adequate test meal consumption and imaging duration) before escalating to investigational adjunctive tests like BSGM.

Scintigraphy remains the reference standard for gastric emptying; document full protocol adherence to support test interpretation.
Consider less invasive/standard tests first and reserve BSGM/EGG for cases where additional phenotyping may affect management and after prior authorization.
Incomplete or nonstandard scintigraphy protocols may reduce interpretability and increase the need for further testing.

ReferenceDefinition references Bharucha et al., 2013a as cited in the policy.

inv-46: Electrogastrography (EGG) — definition

DefinitionElectrogastrography (EGG): a noninvasive method measuring gastric myoelectrical activity using cutaneous electrodes placed on the abdominal skin over the stomach.

Clinical roleEGG has been studied for diagnosis of gastric disorders but evidence is insufficient to support its accuracy or impact on patient management compared with reference standards.

Research recommendationStandardized recording, analysis, and interpretation procedures are needed for EGG utility assessment.

inv-47: 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.

Use casesMay be used when ARM and BET are inconclusive, for preoperative anatomical assessment, or when soft-tissue resolution is needed; evacuation-phase imaging improves sensitivity.

Comparative performanceExisting evidence does not support MRD replacing evacuation proctography (EP) as the reference standard; MRD may function as a triage test but requires further validation.

inv-48: Distensibility Index (DI) — definition

DefinitionDistensibility Index (DI): a measurement of esophagogastric junction opening dynamics calculated as the ratio of cross-sectional area to pressure obtained during volumetric distension with FLIP/EndoFLIP.

Measurement contextDI is measured at the narrowest EGJ perimeter during volumetric distension and recorded alongside cross-sectional area (CSA).

Clinical notationDI is used to assess compliance of the lower esophageal sphincter and should be documented when FLIP is performed.

inv-49: EndoFLIP/FLIP — definition

DefinitionEndoFLIP/FLIP: an endolumenal functional lumen imaging probe system that measures simultaneous pressure and diameter to assess gastrointestinal lumen distensibility and EGJ opening dynamics.

AvailabilityFLIP (EndoFLIP) has been available since 2009 and is FDA-cleared as a measurement tool to guide management of upper GI disorders.

Intended useGuidance documents recommend FLIP be used as a complementary assessment and not as the sole basis for diagnosis or treatment decisions.

inv-50: MRI defecography (MRD) — definition

DefinitionMRI defecography (MRD): dynamic MRI imaging of defecation used to evaluate pelvic floor structural and functional abnormalities; sometimes performed without evacuation-phase imaging.

Technique noteEvacuation-phase imaging increases sensitivity for detecting rectocele and enterocele; MRD performed without evacuation phase has lower sensitivity compared to EP.

Clinical limitationMRD has variable technical success and is not considered a replacement for evacuation proctography; clinical utility requires further high-quality studies.

inv-51: Body Surface Gastric Mapping (BSGM) — definition and example devices referenced

DefinitionBody Surface Gastric Mapping (BSGM): noninvasive surface electrode mapping of gastric myoelectrical activity using multiple body-surface electrodes (e.g., Gastric Alimetry) for phenotyping gastric motility disorders.

Example deviceGastric Alimetry System is referenced as an example of BSGM in the policy's clinical evidence discussion (ECRI assessment cited).

Evidence summaryObservational studies suggest BSGM shows improved frequency stability, symptom correlations, and patient-level classification accuracy compared with traditional EGG, but clinical utility for outcomes is unproven.

inv-52: BSGM (Body Surface Gastric Mapping) — high-resolution mapping definition

DefinitionHigh-resolution BSGM: multi-electrode, noninvasive mapping of gastric electrical activity that derives spectral and spatial biomarkers to characterize gastric function.

Comparative performanceHigh-resolution BSGM demonstrated substantially tighter frequency ranges and greater symptom correlations versus EGG in multicenter observational data, but evidence remains observational.

Need for validationFurther standardized protocols and larger validation studies are needed to establish clinical utility and impact on patient-relevant outcomes.

inv-53: Mucosal Impedance (MI) testing — definition

DefinitionMucosal Impedance (MI) testing: measurement of esophageal epithelial impedance (mucosal integrity) during endoscopy using a balloon catheter or sensing rings to identify patterns associated with GERD, EoE, or non-GERD.

Study evidenceProspective multi-center test-validation studies (e.g., Patel et al., 2019) reported distinct MI patterns among GERD, EoE, and non-GERD cohorts, with validation cohorts demonstrating high sensitivity and specificity in small samples.

LimitationsPublished studies are limited by small sample sizes, lack of blinding, and homogeneous cohorts; clinical utility for replacing standard diagnostics is not established.

inv-54: Achalasia (policy addition) — added defined term per revision

Added definitionAchalasia was added as a defined term in the revised policy definitions; described as a primary esophageal motor disorder with impaired EGJ relaxation and loss of organized peristalsis.

Policy change noteAddition of achalasia as a defined term coincides with policy revisions that list FLIP for achalasia among unproven/not medically necessary procedures.

ReferenceDefinition content aligns with the Definitions section of the policy (ASGE citation).

inv-55: Functional Lumen Imaging Probe (FLIP) — added definition and note that FLIP for achalasia listed as unproven

Added definitionFunctional Lumen Imaging Probe (FLIP): added as a defined term in the policy; a catheter-based endoscopic system to assess esophageal motility and distensibility at the EGJ.

Policy positionThe revised policy notes FLIP technology for diagnosing achalasia is listed among unproven and not medically necessary procedures.

Clinical guidanceGuidelines state FLIP is an adjunctive/complementary tool and clinicians should not make diagnosis or treatment decisions based on FLIP assessment alone.

Examples of body surface gastric mapping and related systems (including Gastric Alimetry System and G-Tech Gut Tracker) and the MiVu™ mucosal integrity testing system were removed from the list of unproven/not medically necessary procedures.

2026-02-01removed_cpt_codes

Several CPT codes (43647, 43648, 43881, 43882, 64590, 64595) were removed from the Applicable Codes section.