CurrentAetnaPolicy 0386

Breast Transillumination, Electrical Impedance Scanning (EIS), and Elastography

Clinical policy governing coverage stance for breast transillumination (optical imaging), electrical impedance scanning (EIS), and elastography techniques for breast cancer detection and characterization; applies to Aetna members and providers submitting claims to Aetna.

Policy Summary

PayerAetna

PolicyBreast Transillumination, Electrical Impedance Scanning (EIS), and Elastography

Policy CodePolicy 0386

Change TypeNo material change

Effective DateFeb 2, 2000

Next Review DateApr 11, 2024

Key ActionWhen submitting claims for these modalities, document indication and prior standard imaging (mammography, diagnostic ultrasound, MRI) because these technologies are considered investigational and may require case‑by‑case review.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

7experimental/investigational items

0.886 / 0.866SWE summary sens / spec

41.1%Reduction in unnecessary biopsies

33studies summarized

12/05/2023last review

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Coverage Determinations

Experimental and Investigational (Not Established)

The following procedures are considered experimental and investigational because effectiveness has not been established:

Experimental/Investigational list: 1. Breast elastography by any method (ultrasound or magnetic resonance); 2. Combined shear-wave elastography with ultrasonography for detection of breast cancer; 3. Electrical impedance scanning (EIS) of the breast for distinguishing benign from malignant breast lesions; 4. Non-elastographic quantitative ultrasound tissue characterization for screening and diagnosis of breast cancer and for all other indications; 5. Optical coherence micro-elastography for identifying malignant tissue and lymph node involvement during breast-conserving surgery; 6. Opto-acoustic imaging of relative blood oxygen saturation and total hemoglobin for diagnosis of breast cancer; 7. Transillumination (optical imaging, light scanning or diaphanography) of the breast for detection of breast cancer.

Listed items are considered experimental/investigational per policy.

Evidence summaries and caveats

Summary of evidence and key caveats from cited studies:

Elastography and related QUS findings: Multiple studies and meta-analyses report high diagnostic performance for elastography (SWE, ARFI, STE) and for some QUS methods when combined with B-mode ultrasound or used for texture-based classification (examples: pooled UE AUC 0.89 for TNBC vs non-TNBC; pooled SWE+US AUC 0.96 with sensitivity 0.971 and specificity 0.801; STE pooled AUC ~90.2%; combined SWE+US reported biopsy reduction ~41.1% and BI-RADS downgrades of 71.3%).

Heterogeneity in methods, cutoffs, and study design limit generalizability; see technical limitations and need for validation.

Evidence limitations and guideline context

Evidence limitations and guideline context relevant to coverage decisions:

Evidence limitations: Studies are encouraging but limited by heterogeneity, small or single-center cohorts, variable methods and cutoffs, and retrospective designs; larger prospective, multi-center validation and standardization are repeatedly recommended.

See meta-analyses and study limitations noted in the literature.

Guideline absence: Non-elastographic QUS and several emerging modalities (including some opto-acoustic approaches) are not mentioned in UpToDate or NCCN breast cancer guidelines.

May prompt additional review or exclusion from standard management pathways.

Technical limitations: Opto-acoustic/photoacoustic imaging faces challenges with optical attenuation, depth penetration and quantification (relative sO2 reported rather than absolute values); these technical limitations affect current clinical translation.

Quantification and depth limitations described in experimental studies.

The policy lists several modalities as experimental and investigational because effectiveness has not been established, including breast elastography (any method) (ultrasound or magnetic resonance), combined shear‑wave elastography with ultrasonography, electrical impedance scanning (EIS) for distinguishing benign from malignant lesions, and other emerging techniques such as non‑elastographic quantitative ultrasound tissue characterization, optical coherence micro‑elastography, opto‑acoustic imaging, and transillumination.

Systematic reviews have not identified effectiveness data supporting use of digital infrared thermal imaging (DITI), EIS, or elastography for population breast cancer screening. A comprehensive review found substantial heterogeneity across studies, no effectiveness trials, and concluded there is insufficient evidence to recommend these technologies for screening.

Available evidence indicates power Doppler ultrasound alone is unsuitable to discriminate local breast cancer recurrence from post‑treatment fibrosis; authors cautioned that relying on Doppler (or elastography/Doppler) alone to avoid biopsy could lead to poorer clinical outcomes compared with biopsying all suspicious masses.

A contemporary UpToDate review of diagnostic evaluation of suspected breast cancer does not reference non‑elastographic quantitative ultrasound (QUS) tissue characterization as a management option, indicating it is not incorporated into that major clinical resource.

Similarly, the National Comprehensive Cancer Network (NCCN) Breast Cancer guideline (Version 2.2022) does not describe non‑elastographic QUS tissue characterization as a diagnostic or screening strategy, reflecting absence from major practice guidelines.

Because these techniques lack established effectiveness and guideline endorsement, the policy considers them experimental/investigational. This classification underlies the exclusion from established coverage and informs that claims for these services may be subject to noncoverage or denial.

The evidence base contains no effectiveness studies and shows wide variability in diagnostic accuracy measures across trials; therefore there is insufficient evidence to support EIS, DITI, or elastography as stand‑alone screening tools for breast cancer.

Authors have warned that using shear‑wave elastography (SWE) or Doppler findings alone to defer biopsy of suspicious lesions may worsen clinical outcomes compared with the current standard practice of performing biopsies on all suspicious masses.

Many studies cited are limited by small sample sizes, retrospective designs, and single‑instrument or single‑center cohorts. These methodological limitations and heterogeneity in techniques and cut‑off values reduce confidence in generalizability and warrant larger, prospective multicenter validation before routine adoption.

Given the lack of guideline inclusion and the limited, heterogeneous evidence base, non‑elastographic quantitative ultrasound (QUS) is not supported as a primary diagnostic or screening modality for breast cancer at this time.

Indications and Adjunctive Uses

Detection or characterization of breast lesions/breast cancer using listed investigational modalities

Use of the listed investigational modalities for detection or characterization of breast lesions/breast cancer is considered investigational:

Investigational modalities for breast imaging: Use of transillumination/optical imaging, electrical impedance scanning (EIS), elastography (ultrasound or MR), non-elastographic quantitative ultrasound, opto-acoustic/photoacoustic imaging, and optical coherence micro-elastography for detection or characterization of breast cancer is investigational and not an accepted substitute for standard mammography or established imaging modalities.

Background and policy scope describe investigational status.

Adjunctive use of elastography for characterization of focal breast lesions in symptomatic patients or for further evaluation of indeterminate imaging findings

Adjunctive elastography use has been studied but remains investigational per policy:

Elastography adjunct use: Elastography (strain or shear-wave) has been studied as an adjunct to conventional breast ultrasound or MRI to help characterize focal breast lesions and may improve specificity and diagnostic accuracy when combined with conventional imaging; however, study heterogeneity and need for validation limit established effectiveness.

Billing Codes and Technical Parameters

CPT/HCPCS codes related to the bulletinmixed

0351T	Optical coherence tomography of breast or axillary lymph node, excised tissue, each specimen
0352T	Optical coherence tomography of breast or axillary lymph node, excised tissue, each specimen
0353T	Optical coherence tomography of breast, surgical cavity
0354T	Optical coherence tomography of breast, surgical cavity
0689T	Quantitative ultrasound tissue characterization (non-elastographic), including interpretation and report, obtained without diagnostic ultrasound examination of the same anatomy (eg, organ, gland, tissue, target structure)
0690T	Quantitative ultrasound tissue characterization (non-elastographic), including interpretation and report, obtained with diagnostic ultrasound examination of the same anatomy (eg, organ, gland, tissue, target structure) (List separately in addition to code for primary procedure)
76391	Magnetic resonance (eg, vibration) elastography
76981	Ultrasound, elastography; parenchyma (eg, organ)
76982	Ultrasound, elastography
76983	Ultrasound, elastography

1–10 of 16

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ICD-10 diagnosis codes referencedICD-10

C50.011	Malignant neoplasm of breast (example start of malignant codes list)
C50.929	Malignant neoplasm of breast
C79.81	Secondary malignant neoplasm of the breast
D05.00	Carcinoma in situ of breast
D05.92	Carcinoma in situ of breast (end range listed)
D24.1	Benign neoplasm of breast
D24.9	Benign neoplasm of breast
N60.01	Disorder of breast (example start of range)
N65.1	Disorders of breast (range end)
Z12.39	Encounter for other screening for malignant neoplasm of breast

Codes referencedmixed

No codes listed

Device/Regulatory identifiers citedmixed

K083095

FDA 510(k) Regen SonixTouch Ultrasound Scanner (example device referenced)

SWE cut-off values

Reported SWE cut-off range30 to 145.9 kPa (cut-off values reported across studies)

Reason for range variabilityHeterogeneity among studies prevented identification of a single optimal cut-off value

Implication for interpretationCut-off selection is technique- and study-dependent; larger standardized studies needed

Provider Requirements and Operational Notes

Prior Authorization

Codes affected — prior authorization note

Codes listed in the policy are associated with the experimental/investigational determinations above; prior authorization requirements for these codes (if any) follow standard payer rules. Providers should submit appropriate documentation when requesting coverage and be aware services such as elastography, quantitative ultrasound tissue characterization, opto-acoustic imaging, and related CPT/HCPCS codes may be denied as experimental/investigational.

Affected CPT/HCPCS (examples listed in policy): 0351T–0354T, 0689T–0690T, 76391, 76981–76983, 19301–19302, 77065–77067
Affected HCPCS: C9788
ICD-10 examples listed in policy: C50.xx, C79.81, D05.xx, D24.xx, N60.01–N65.1, Z12.39

Documentation Required

Provide prior standard imaging and indication

When these imaging techniques are used clinically, include the clinical indication and prior standard imaging results (mammography, diagnostic ultrasound, MRI) in the request and report. Documenting prior imaging and the reason additional testing is being pursued facilitates interpretation and any utilization review.

Prior Authorization Notes

Prior Authorization

Elastography / QUS — prior auth not specified

Elastography/QUS prior authorization status is listed as 'not specified' in the imaging prior authorization notes; check the full policy or payer prior authorization rules for any submission requirements.

Imaging prior auth notes: Elastography / QUS — not specified.

Prior Authorization

Opto‑acoustic/EIS/QUS — use as primary diagnostic/screening modality may require review

The policy describes opto‑acoustic/photoacoustic imaging, EIS, and non‑elastographic QUS tissue characterization as emerging modalities and indicates they are not supported as primary diagnostic or screening modalities; case‑by‑case review or prior authorization may be required if billed as such.

Policy note: use as primary diagnostic/screening modality may prompt review.

Contrast and Imaging Agent Notes

Billing Rule

Opto‑acoustic imaging — no exogenous contrast or ionizing radiation

Opto‑acoustic imaging generates maps of blood oxygen saturation and total hemoglobin using endogenous optical contrast, without injection of exogenous contrast agents or use of ionizing radiation.

Policy: images of blood oxygen saturation and total hemoglobin are generated using endogenous contrast without external contrast or ionizing radiation.

Billing Rule

Contrast rules — opto‑acoustic uses endogenous hemoglobin contrast

Opto‑acoustic (photoacoustic) imaging uses endogenous hemoglobin contrast and does not require exogenous contrast agents for generation of functional blood oxygenation or hemoglobin maps.

The policy describes opto‑acoustic imaging as producing diagnostic images via endogenous optical contrast.

Definitions and Technical Terms

Mammography remains the generally accepted standard for breast cancer screening and diagnosis. Novel imaging techniques such as optical/transillumination, EIS, elastography (ultrasound and MR), opto‑acoustic/photoacoustic imaging, and quantitative ultrasound approaches have been investigated to address limitations like dense breast tissue and lesion characterization, but most are investigational and lack established clinical utility.

Breast transillumination / optical imaging — definition

DefinitionTechniques that pass light through or reflect light off the breast and measure returned light intensity (also called light scanning, diaphanography, optical imaging, optical mammography, dynamic optical breast imaging, diffuse optical spectroscopy).

PurposeUsed to detect tumors or visualize blood vessels supplying tumors by exploiting differences in light absorption/reflection between normal and abnormal tissues.

Example systemsComputed Tomography Laser Mammography (CTLM) – near-infrared laser system measuring hemoglobin absorption; opto-acoustic tomography (hybrid optic-acoustic method).

Electrical impedance scanning (EIS) — definition

Explicit Not-Covered Statements

Not covered: Breast elastography (ultrasound or MRI) for detection or characterization of breast cancer; combined shear‑wave elastography with ultrasonography; and other listed investigational modalities including opto‑acoustic imaging, optical coherence micro‑elastography, non‑elastographic QUS, EIS, and transillumination are considered investigational and excluded from established coverage.

Policy Summary

PayerAetna

PolicyBreast Transillumination, Electrical Impedance Scanning (EIS), and Elastography

Policy CodePolicy 0386

Change TypeNo material change

Effective DateFeb 2, 2000

Next Review DateApr 11, 2024

SourceLink

On This Page

Examples include improved specificity and combined-modality AUC gains reported in multiple studies and meta-analyses.

Adjunctive use of SWE/STE/MRE for characterization of breast masses

Shear-wave and related elastography techniques have shown promising diagnostic performance in studies:

SWE/STE/MRE adjunct use: Adjunct use of shear-wave elastography (SWE), sound touch elastography (STE), and magnetic resonance elastography (MRE) to characterize breast masses has demonstrated improved diagnostic metrics (higher AUC, sensitivity and specificity in pooled analyses) but variability in cutoffs and study designs necessitates further standardization before established clinical use.

Meta-analyses report high pooled AUCs and pooled sensitivities/specificities; cut-off values vary across studies.

Intraoperative margin and lymph node assessment (research/early feasibility)

Investigational intraoperative applications are early-feasibility and research-stage:

Intraoperative assessment (research): Optical coherence micro-elastography (OCME) has been investigated for intraoperative assessment of lumpectomy margins and for imaging of axillary lymph nodes in fresh specimens to identify malignant involvement; feasibility demonstrated but diagnostic accuracy and acquisition time require further study.

Feasibility studies imaged fresh specimens and recommended further work before clinical adoption.

Adjunct to B-mode ultrasound for characterization of suspicious breast lesions

Adjunct to B-mode ultrasound — potential benefits reported but not established as standard of care:

Adjunct to B-mode US: Adding shear-wave elastography or ARFI-derived measures to B-mode ultrasound has been shown in studies to improve specificity, assist differentiation of inflammatory versus malignant lesions, and reduce unnecessary biopsies; variability in thresholds and methods limits routine clinical adoption.

Reported biopsy reduction and BI-RADS downgrades in pooled analyses; technique-dependent cutoffs.

Predicting response to neoadjuvant chemotherapy (investigational)

Investigational role in predicting treatment response:

Predicting response to neoadjuvant chemotherapy: Non-elastographic quantitative ultrasound (QUS) multi-parametric imaging and texture-analysis models have been used to predict response to neoadjuvant chemotherapy with reported accuracies up to ~84-85% and AUCs around 0.86-0.89 in multi-center cohorts; promising but requires larger validation prior to clinical use.

Studies reported multi-center data and model performance metrics; further external validation recommended.

Adjunctive or investigational imaging to assist lesion characterization or research applications

Adjunctive or investigational imaging applications under investigation:

Investigational/adjunctive imaging: Various emerging imaging techniques (opto-acoustic/photoacoustic imaging, non-elastographic QUS, transillumination, and EIS) have been explored to assist lesion characterization, map tumor oxygenation/hemoglobin, or identify intra-tumor heterogeneity for research and predictive applications; these remain investigational pending standardized validation and guideline inclusion.

Technical and study limitations such as penetration depth, quantification accuracy, and lack of guideline endorsement are noted.

Provide prior standard imaging: screening or diagnostic mammography, diagnostic ultrasound, and MRI findings when available
State specific clinical indication and prior imaging dates/results in the request/report

Denial Risk

Screening use unsupported

Current evidence is insufficient to support routine use of DITI, EIS, non-elastographic QUS, opto-acoustic imaging, transillumination, or elastography for breast cancer screening. These modalities are not recommended as replacements for established screening (mammography) and may be considered investigational.

Screening use unsupported: DITI, EIS, non-elastographic QUS, elastography, opto-acoustic imaging, transillumination

Denial Risk

Use of elastography methods to determine biopsy — caution

Evidence suggests caution when relying on elastography-derived parameters to decide against biopsy for suspicious masses. Use of elastography alone to defer biopsy may lead to poorer outcomes compared with performing biopsies on all suspicious lesions.

Elastography should not be used in isolation to rule out biopsy for suspicious masses
Ensure histologic confirmation when clinical concern persists

Note

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Billing Rule

Guideline absence may prompt review

Absence from major guidelines (e.g., UpToDate, NCCN) for many of these technologies may prompt individual case review when requested; lack of guideline support is a consideration for denial or for requiring additional documentation.

Guideline absence may prompt case-by-case review
Requests may require supplemental clinical justification and prior imaging/pathology

Note

Clinical Policy Bulletins are developed to assist in administering plan benefits

Clinical Policy Bulletins are developed to assist in administering plan benefits and do not guarantee coverage. Providers remain responsible for clinical decisions and should follow the plan's documentation and authorization processes.

CPBs are administrative guidance — not coverage guarantees
Follow payer-specific prior authorization and documentation procedures

Documentation Required

Quantitative SWE reporting — document parameters

When shear-wave elastography (SWE) quantitative measures are reported, document technical parameters to aid interpretation — including ROI selection and reported stiffness metrics such as mean elasticity (Emean) and maximum elasticity (Emax).

Report ROI size/location and device/technique
Include quantitative SWE parameters: Emean, Emax (and specify units)

Documentation Required

Studies cited require histological confirmation

Many diagnostic accuracy studies cited in the evidence base required histological confirmation as the reference standard. When applicable, include pathology results or plan for histologic confirmation in the care pathway.

Studies cited use histopathology as reference standard — document biopsy/surgical pathology when available
Retrospective study designs and selection criteria may limit generalizability

Documentation Required

Adjunctive use after standard imaging

These modalities are primarily discussed as adjuncts to standard imaging in the literature; consider them only after conventional imaging pathways (mammography, diagnostic ultrasound, MRI) have been applied and documented.

Adjunctive use after standard imaging: elastography and other emerging modalities may be considered only with prior conventional imaging documented
Do not substitute these technologies for standard diagnostic or screening modalities

DefinitionTechnique that transmits small electrical currents into the body and measures surface impedance patterns via probes on the skin; malignant and normal tissues conduct electricity differently.

RationaleExperimental studies show malignant breast tumors may have lower electrical impedance than surrounding tissue, suggesting potential for lesion detection.

Evidence statusNo prospective clinical studies demonstrating clinical utility to distinguish benign from malignant lesions; further investigation needed.

Elastography — definition

DefinitionMeasurement of tissue elastic properties (stiffness) based on the principle that malignant tissue is generally harder than benign tissue; typically performed with ultrasound (strain imaging, sonoelastography, shear-wave tracking) or studied with MRI (MRE).

Main US types1) Strain imaging (tracks tissue movement during compression); 2) Sonoelastography (color Doppler to image tissue movement); 3) Shear-wave tracking (measures shear wave propagation to obtain elastic modulus).

Clinical roleInvestigated as an adjunct to conventional imaging to help characterize focal breast lesions; MR elastography offers quantitative shear modulus measures.

Magnetic resonance elastography (MRE) — definition

DefinitionAn MRI-based, phase‑contrast technique that visualizes and quantitatively measures propagating shear strain waves in tissue under harmonic mechanical excitation to calculate local shear modulus (elasticity/stiffness).

ApplicationUsed to assess viscoelastic properties of breast tumors and surrounding tissues; provides quantitative elasticity values (kPa).

Evidence noteEarly MRE studies showed overlap in elasticity ranges between some malignant and benign lesions, indicating limited separation in some cases.

Strain ratio / length ratio — definition

DefinitionQuantitative strain measurements in ultrasound elastography that compare lesion deformation to reference tissue (e.g., strain ratio or length ratio) to help differentiate benign from malignant masses.

PerformanceMeta-analysis reported pooled strain ratio sensitivity ~88% and specificity ~83%; length ratio showed high sensitivity (~98%) with variable specificity.

Clinical implicationMay augment B-mode ultrasound but requires further comparative effectiveness and standardization studies.

Shear wave elastography (SWE) — definition

DefinitionAn ultrasound elastography technique that generates quantifiable elasticity values (reported in kPa or shear wave velocity) by inducing and measuring shear waves in tissue; often combined with B-mode US for lesion characterization.

MetricsCommonly reported metrics include minimum, mean, and maximum elasticity (kPa) and mass/fat elasticity ratios; cut-off values vary by study.

Evidence summaryMeta-analyses and studies report high pooled sensitivity and specificity and show that adding SWE to B-mode US can improve specificity and reduce unnecessary biopsies, though heterogeneity exists.

stiffness gradient — definition

DefinitionA quantitative heterogeneity parameter computed from mean and maximum measured elasticity (derived from SWE) intended to capture intra‑lesion stiffness variation and improve specificity in diagnosis.

PerformanceIn systematic review, stiffness gradient outperformed maximum elasticity for stratifying malignancy risk (improvement margins reported for different ROI methods).

Methodological noteROI selection method substantially affects measured elasticity values and derived heterogeneity metrics; standardization is needed.

SWE score / maximum elasticity — definition

DefinitionA qualitative 5-point scale (SWE score) and a quantitative maximum elasticity (or velocity) metric derived from SWE used to categorize lesion stiffness; higher scores/values suggest greater likelihood of malignancy.

ExamplesStudy classified SWE score ≥3 as positive (sensitivity 87%); SWE maximum elasticity (velocity >6.5 cm/s) showed sensitivity 87% and specificity 77.8% for recurrence assessment.

Use caseApplied as adjunctive measures with power Doppler and B‑mode US for evaluating suspected local recurrence and distinguishing recurrence from fibrosis.

SWE (Shear-wave elastography) — definition

DefinitionShear-wave elastography (SWE): an ultrasound elastography technique measuring tissue stiffness by generating and detecting shear waves; outputs include kPa and shear wave velocity and is typically combined with B-mode ultrasound to improve specificity and reduce unnecessary biopsies.

Diagnostic impactMeta-analyses report high pooled sensitivity/specificity and improved AUC when SWE is added to conventional ultrasound (pooled AUCs up to ~0.96).

LimitationsCut-off values and techniques vary across studies; further standardization and larger prospective validation are needed.

ARFI (Acoustic Radiation Force Impulse) elastography — definition

DefinitionAcoustic Radiation Force Impulse (ARFI) elastography: a quantitative elastography method that measures shear-wave velocity (m/s) generated by acoustic radiation force to differentiate lesion types.

MetricsReports use mean shear-wave velocity (SWV) to compare conditions (e.g., IGM mean SWV 3.78 m/s vs IDC 5.34 m/s) with diagnostic sensitivity and specificity derived from qualitative and quantitative patterns.

Clinical noteCombining qualitative pattern assessment with quantitative SWV can improve differentiation between inflammatory and malignant lesions.

QUS (Quantitative Ultrasound) spectroscopy — definition

DefinitionQuantitative Ultrasound (QUS) spectroscopy: analysis of ultrasound radio-frequency (RF) backscatter parameters (e.g., MBF, SS, SI, ASD, AAC) and texture features to characterize breast lesions and to develop predictive models (e.g., for therapy response).

ApplicationsUsed to generate parametric images and texture-derived features from tumor core and margins to build response-prediction models for neoadjuvant chemotherapy with reported accuracies and AUCs.

Evidence statusPromising multi-center studies exist, but larger populations and further validation are needed prior to routine clinical adoption.

Opto-acoustic imaging — definition

DefinitionOpto-acoustic imaging (photoacoustic imaging): uses pulsed light to generate ultrasound signals from tissue; multispectral acquisition enables mapping of blood oxygen saturation and total hemoglobin using endogenous optical contrast without exogenous contrast agents.

Imaging capabilityCan visualize blood and oxygenation differences in tissue; phantoms demonstrated vessel visibility to depths up to ~48 mm depending on wavelength and oxygenation.

Clinical potentialInvestigated for lesion characterization to distinguish benign from malignant lesions and potentially reduce unnecessary biopsies; quantification and penetration limitations noted.

Opto‑acoustic/photoacoustic imaging — definition (alternate)

Definition (alternate)Opto‑acoustic/photoacoustic imaging: an imaging technique using light to induce sound waves that are detected to produce images of blood oxygen saturation and total hemoglobin without exogenous contrast or ionizing radiation.

Key featureUses endogenous hemoglobin contrast across multiple wavelengths to generate colorized parametric maps of oxygenation and hemoglobin concentration.

LimitationsPenetration depth and quantification challenges exist; imaging depth and hematocrit affect vessel visibility and oxygenation contrast.

Electrical Impedance Scanning (EIS) — definition (alternate)

Definition (alternate)Electrical Impedance Scanning (EIS): imaging techniques that measure bioelectrical impedance differences in breast tissue by transmitting current and recording surface impedance patterns, with malignant tissue often appearing as areas of altered impedance.

Evidence caveatClinical data are insufficient; no prospective clinical studies demonstrate utility for distinguishing benign from malignant lesions as adjunct or substitute to established imaging.

Historical assessmentInstitute of Medicine (2001) concluded clinical data suggest potential role but more study needed to define role relative to existing technologies.

Elastography — ultrasound elastography definition (alternate)

Definition (alternate)Ultrasound elastography: ultrasound-based methods (strain imaging, sonoelastography, shear-wave elastography) that assess tissue elasticity/stiffness to aid differentiation of benign and malignant breast lesions by providing qualitative and quantitative stiffness metrics.

Technique notesMultiple implementations exist (strain ratio, length ratio, mean/max elasticity, stiffness gradient); ROI selection and acquisition method affect reported values.

Evidence summaryMeta-analyses report high diagnostic performance for various elastography metrics, but heterogeneity and need for standardization remain limitations.

Clinical Policy Bulletin — Aetna policy document definition

DefinitionClinical Policy Bulletin: an Aetna-developed document intended to assist in administering plan benefits; it does not constitute a guarantee of coverage or medical advice.

Administrative infoPolicy displays last review date (12/05/2023), effective date (02/02/2000), and next review date (04/11/2024).

Usage noteProviders should consult the full Clinical Policy Bulletin for complete coverage criteria and plan-specific provisions.