CMS Modified NCD 4 for Diathermy and Ultrasound Heat Treatment for Pulmonary Conditions, Effective January 9, 2026 — What Billing Teams Need to Know

TL;DR: The Centers for Medicare & Medicaid Services modified NCD 4, its national coverage determination for heat treatment (including diathermy and ultrasound) for pulmonary conditions, effective January 9, 2026. The policy maintains a blanket non-coverage position. No specific CPT or HCPCS codes are listed in the policy document.

This update to the CMS diathermy and ultrasound coverage policy reaffirms what Medicare has long held: there is no valid scientific basis for using diathermy or ultrasound heat treatments on pulmonary conditions like asthma or bronchitis. If your team is billing — or thinking about billing — these services for pulmonary indications under Medicare, stop. The coverage policy under NCD 4 in the Medicare system is unambiguous, and claim denial is a near-certainty.

Quick-Reference Table

CMS Diathermy and Ultrasound Heat Treatment Coverage Criteria and Medical Necessity Requirements 2026

NCD 4 is the National Coverage Determination governing Medicare's position on heat treatments — including shortwave diathermy, microwave diathermy, ultrasound, and related thermal therapies — when billed for pulmonary conditions.

The medical necessity standard here is clear, and it isn't borderline. CMS states directly that there is no physiological rationale and no valid scientific documentation supporting the effectiveness of diathermy or ultrasound heat treatments for asthma, bronchitis, or any other pulmonary condition. Because of this, CMS does not consider these services reasonable and necessary under Section 1862(a)(1) of the Social Security Act.

That's the statutory anchor. Section 1862(a)(1) is the "reasonable and necessary" requirement — the bedrock of Medicare coverage. When CMS says a service fails that standard, it's not a gray area. It's a hard stop.

The January 9, 2026 effective date marks this version of the policy as modified. The clinical position itself hasn't shifted — CMS has held this non-coverage stance on heat treatment for pulmonary conditions for years. What billing teams should register is that this policy was formally reviewed and updated, which means it's active and enforceable. Medicare Administrative Contractors will apply this standard when processing claims.

There is no prior authorization pathway that unlocks reimbursement here. Prior auth doesn't help when the underlying coverage policy excludes the service entirely. You can't get an authorization for a non-covered service and expect it to hold up on audit.

CMS Diathermy and Ultrasound Heat Treatment Exclusions and Non-Covered Indications

This entire NCD is built around non-coverage. That's the point. Diathermy and ultrasound heat treatment for pulmonary conditions doesn't just lack prior authorization support — it lacks coverage support entirely under NCD 4 in the Medicare system.

CMS names asthma and bronchitis specifically, then extends the exclusion to "any other pulmonary condition." That language matters. This isn't a narrow carve-out for two diagnoses. Any pulmonary indication — COPD, emphysema, chronic respiratory failure, pulmonary fibrosis — falls under the same non-covered determination.

The policy cross-references NCD Manual Section 150.5, which covers the broader category of ultrasound therapy. If your billing guidelines currently include ultrasound for any pulmonary indication, Section 150.5 is also worth reviewing alongside NCD 4.

The real issue here is that some practices may have inherited charge capture rules from older systems or less experienced billers who assumed heat therapy is heat therapy — and that a physical therapy or rehabilitation code would just pass through. It won't, not when the associated diagnosis is pulmonary.

Coverage Indications at a Glance

CMS Diathermy and Ultrasound Heat Treatment Billing Guidelines and Action Items 2026

The following steps apply to any practice that provides heat therapy services — including physical therapy departments, rehabilitation medicine, and pulmonology practices — and bills Medicare.

If your practice has a high volume of pulmonary patients who also receive physical therapy or rehabilitation services, talk to your compliance officer before the effective date of January 9, 2026 passes without action. The exposure may be small — or it may be worth a formal billing audit.

CPT, HCPCS, and ICD-10 Codes for Diathermy and Ultrasound Heat Treatment Under NCD 4

A Note on Codes

The NCD 4 policy document does not list specific CPT or HCPCS codes. This is uncommon but not unheard of for older NCDs that predate the modern code-level specificity of more recent coverage determinations.

This does not limit the policy's force. The non-coverage determination applies based on the clinical indication — pulmonary conditions — regardless of which procedure code is billed. If you bill a diathermy or ultrasound heat treatment service using any applicable code, and the associated diagnosis is pulmonary, Medicare will deny it under NCD 4.

For reference, common procedure codes associated with these therapies in other contexts include diathermy and ultrasound physical therapy codes. Your Medicare Administrative Contractor may publish a Local Coverage Determination (LCD) that provides more code-level detail. Check with your regional MAC if you need specific code guidance.

Not Covered — All Pulmonary Indications

Note: No specific CPT, HCPCS, or ICD-10 codes are listed in the NCD 4 policy document. Consult your MAC's LCD or contact your MAC directly for code-specific guidance.