CMS FDG PET for Refractory Seizures: NCD 294 Coverage Policy Update (2026)

CMS has issued a modification to National Coverage Determination 294, which governs Medicare coverage of FDG-PET imaging for pre-surgical evaluation of refractory seizures. If your facility or practice performs—or refers for—fluorodeoxyglucose positron emission tomography in epilepsy patients, this update warrants a close review of your documentation and billing workflows. Here's what the policy says, what it requires, and what your team should do now.

What CMS NCD 294 Covers: FDG-PET for Refractory Seizure Localization

The Centers for Medicare & Medicaid Services established coverage for FDG-PET in the context of refractory seizures effective July 1, 2001, and NCD 294 has governed that coverage ever since. The 2026 modification updates the policy record — meaning billing teams need to treat this as a live, active document requiring fresh review rather than a static legacy policy.

Under NCD 294, Medicare covers FDG-PET imaging specifically for pre-surgical evaluation when the clinical goal is to localize a focus of refractory seizure activity. That's a narrow, well-defined indication, and every claim touching this policy should be evaluated against it precisely.

The policy falls under the Medicare benefit category of Diagnostic Tests (other). It is also cross-referenced to the broader PET Scans NCD (§220.6), which governs PET imaging coverage more generally — a critical detail for facilities billing FDG-PET across multiple indications.

Coverage Criteria: What Medicare Requires for FDG-PET Refractory Seizure Claims

CMS coverage under NCD 294 hinges on a specific clinical context. The imaging must be performed as part of a pre-surgical evaluation — not for ongoing monitoring, diagnostic confirmation outside a surgical workup, or any other clinical purpose related to epilepsy management.

The covered indication:

The limitation:

This is a hard coverage limit, not a soft guideline. Claims submitted without documentation supporting the pre-surgical evaluation context are at significant risk for denial or recoupment.

Documentation Requirements Under NCD 294

CMS is explicit about where medical necessity documentation must live: the referring physician's records. The policy states that documentation confirming the covered indication should be maintained by the referring physician in the beneficiary's medical record as standard practice.

This has direct implications for how your billing team approaches claims:

• The imaging facility or hospital submitting the claim is not solely responsible for documentation — the referring physician's chart is the primary evidence of medical necessity
• If your facility is the imaging provider, you need a process to obtain or confirm that the referring physician has documented the pre-surgical evaluation context before you submit
• Audits and post-payment reviews will look to the referring physician's record, not just the imaging report, to confirm coverage criteria are met

This referral-source documentation requirement is worth building into your intake and authorization workflows explicitly. A clean imaging report is not sufficient on its own if the ordering physician's record doesn't reflect the pre-surgical evaluation rationale.

Prior Authorization and Claims Processing for FDG-PET Under Medicare

NCD 294 does not specify a prior authorization requirement within the policy text itself. However, billing teams should be aware that Medicare Advantage plans — which follow NCD guidance as a floor but may layer additional requirements on top — often do require prior auth for PET imaging. If your patient population includes Medicare Advantage enrollees, prior authorization rules from the specific plan apply separately from this NCD.

For traditional Medicare fee-for-service, claims processing instructions reference Transmittal 527 of the Medicare Claims Processing Manual (R527CP). Your billing team should confirm that claims are coded and submitted in alignment with those instructions.

Affected Codes

The policy data for NCD 294 does not list specific CPT or HCPCS codes. Billing teams should reference the cross-referenced PET Scans NCD (§220.6) for applicable procedure codes associated with FDG-PET imaging, and confirm current code assignments with your Medicare Administrative Contractor (MAC). No ICD-10-CM diagnosis codes are enumerated in the policy document.

What this means operationally: The absence of enumerated codes in NCD 294 itself makes MAC-level guidance and the §220.6 cross-reference especially important. Do not assume that any FDG-PET code is automatically covered under this NCD without confirming the full coding and clinical context against both NCDs and your MAC's local guidance.

What Your Billing Team Should Do