CurrentBlue Cross Blue Shield - Rhode IslandPolicy N/A

Electrogastrography (EGG) — Medical Coverage Policy

Policy on medical coverage and applicability of electrogastrography (cutaneous recording of gastric electrical activity) for Blue Cross Blue Shield - Rhode Island products, including Commercial and BlueCHiP for Medicare.

Policy Summary

PayerBlue Cross Blue Shield - Rhode Island

PolicyElectrogastrography (EGG) — Medical Coverage Policy

Policy CodePolicy N/A

Change TypeNo material change

Effective Date2001

Next Review DateN/A

Key ActionDo not submit prior authorization; EGG CPT codes 91132 and 91133 are listed as not covered/not medically necessary and are likely to be denied.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

2CPT codes listed as not covered / not medically necessary

2001Effective year

2019-02-19Policy last updated

Commercial & MedicareProducts explicitly addressed

Coverage Criteria — Electrogastrography (EGG)

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Not Medically Necessary / Not Covered

Covered when ALL of the following are met:

Overall coverage stance: EGG is considered not covered/not medically necessary because evidence is insufficient to determine effects on health outcomes and there are inadequate data validating technical feasibility, diagnostic performance, or clinical utility.

Applies to BlueCHiP for Medicare and Commercial Products as stated.

The rationale for noncoverage and the determination of not medically necessary is that published peer‑reviewed literature provides inadequate data on key validation principles: technical feasibility of the test, basic diagnostic performance measures (sensitivity, specificity, predictive values) compared to standards, and evidence that test results change management in ways that improve health outcomes. Because these elements are not sufficiently validated, electrogastrography lacks proven clinical utility.

Provider Actions and Billing Notes

Note

Prior Authorization

Prior authorization is not applicable for Electrogastrography (EGG).

Step Therapy

Step Therapy / Benefit Variance

There is no step therapy requirement for EGG under this policy. Always confirm member benefits and any contract-specific requirements before proceeding.

Documentation Required

Benefit Verification

Verify the member's coverage by checking the member's Benefit Booklet, Evidence of Coverage (EOC), or Subscriber Agreement. Benefits may vary by group and contract; the member's plan documents and eligibility must be confirmed prior to scheduling or billing.

Refer to member's Benefit Booklet/Evidence of Coverage/Subscriber Agreement for member-specific coverage and billing guidance
Contact the provider call center for member-specific benefits and eligibility questions

Denial Risk

Denial Risk for EGG

Denial risk: Electrogastrography (EGG) is not covered for BlueCHiP for Medicare and considered not medically necessary for Commercial Products. The following CPT codes are listed as not covered / not medically necessary and may be denied if billed:

CPT 91132 — Electrogastrography, diagnostic, transcutaneous
CPT 91133 — Electrogastrography, diagnostic, transcutaneous; with provocative testing

Background — Electrogastrography and Clinical Context

Electrogastrography (EGG) records cutaneous gastric myoelectrical activity and has been studied primarily in conditions such as gastroparesis and functional dyspepsia. EGG validation requires demonstration of technical feasibility, reliable diagnostic accuracy compared with reference standards, and evidence that test results lead to management changes that improve patient outcomes; the literature reviewed did not provide adequate data for these requirements.

Definitions

Electrogastrography (EGG): definition and key features

DefinitionRecording and interpretation of electrical activity of the stomach from cutaneous electrodes.

Signal characteristicsEGG records gastric electrical control activity (ECA) and electrical response activity (ERA); usual frequency ~3 cycles per minute, deviations termed brady- or tachyarrhythmia.

Technical considerationsCutaneous signals are relatively weak and susceptible to artifact from cardiac, respiratory, duodenal, and colonic activity; automated filtering and spectral analysis commonly used.

Typical recording practiceMultiple cutaneous electrodes placed on standardized abdominal positions; the channel with highest amplitude is selected for analysis.

Gastroparesis: definition and clinical context

DefinitionChronic disorder of gastric motility characterized by delayed gastric emptying of a solid meal, associated with symptoms such as bloating, distention, nausea, and vomiting.

Common causes/associationsMost commonly associated with diabetes; also linked to chronic obstruction, connective tissue disorders, Parkinson’s disease, and psychological conditions.

Complications of severe diseaseSevere, chronic gastroparesis can be associated with dehydration, poor nutritional status, and poor glycemic control in diabetics.

Diagnostic standardScintigraphic gastric emptying (solid meal with 99mTc) is the standard test; delayed emptying defined as >50% retention at study end.