CMS Modified NCD 288 for FDG PET in Dementia Diagnosis, Effective January 9, 2026 — What Billing Teams Need to Know

TL;DR: The Centers for Medicare & Medicaid Services modified NCD 288, the national coverage determination governing FDG PET scans for dementia and neurodegenerative disease diagnosis, effective January 9, 2026. If your facility or your referring providers bill for FDG PET in dementia workups, the documentation and eligibility requirements under this coverage policy are detailed and unforgiving — and claim denials are likely if you're not tracking all seven prerequisite criteria.

The policy does not list specific CPT or HCPCS codes in the updated version. Work with your coding team to confirm the correct PET imaging codes in your charge capture system against the criteria in NCD 288 Medicare documentation. Neurology, psychiatry, nuclear medicine, and radiology practices are all in scope.

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Field	Detail
Payer	CMS (Centers for Medicare & Medicaid Services)
Policy	FDG PET for Dementia and Neurodegenerative Diseases
Policy Code	NCD 288
Change Type	Modified
Effective Date	January 9, 2026
Impact Level	High
Specialties Affected	Neurology, Psychiatry, Nuclear Medicine, Radiology, Geriatrics
Key Action	Audit all FDG PET orders for dementia indications against NCD 288's seven-point medical necessity checklist before January 9, 2026

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CMS FDG PET Coverage Criteria and Medical Necessity Requirements 2026

The CMS FDG PET coverage policy under NCD 288 covers FDG PET scans in exactly two situations. First, for the differential diagnosis of fronto-temporal dementia (FTD) versus Alzheimer's disease (AD). Second, for use in a CMS-approved practical clinical trial focused on FDG PET's role in diagnosing or treating dementing neurodegenerative diseases.

That second pathway — the clinical trial route — is narrow. Most of your volume will come through the first pathway. That's where the documentation requirements get dense.

The Seven Prerequisites for Covered FDG PET in AD vs. FTD Differential Diagnosis

CMS requires all seven of the following before an FDG PET scan qualifies as reasonable and necessary. Miss one, and you're looking at a claim denial.

1. Recent dementia diagnosis with documented cognitive decline of at least six months. The patient must have a confirmed dementia diagnosis. Cognitive decline must be formally documented — not just noted in a progress note — for a minimum of six months.

2. FTD is a suspected alternative cause. The clinical presentation must raise FTD as a plausible diagnosis. CMS specifically calls out symptoms like social disinhibition, awkward behavior, language difficulties, or loss of executive function appearing early in the disease course. These symptoms are more characteristic of FTD than the memory-dominant presentation typical of AD.

3. A comprehensive clinical evaluation has been completed. This evaluation must meet American Academy of Neurology standards. It includes medical history from both the patient and a well-acquainted informant, assessment of activities of daily living, physical and mental status examination, formal cognitive decline documentation over at least six months using cognitive scales or neuropsychological testing, laboratory tests, and structural imaging — MRI or CT.

4. The evaluation was performed by a physician experienced in dementia diagnosis. A general practitioner ordering an FDG PET without documented dementia expertise on the evaluating physician's part creates a coverage problem. Document who conducted the evaluation and their relevant experience.

5. The diagnosis remains uncertain after full evaluation. FDG PET is only covered when the prior workup — including that comprehensive AAN-standard evaluation — did not clearly determine a specific neurodegenerative disease or other cause. If the diagnosis is already clear, the scan is not covered.

6. No prior SPECT or FDG PET was obtained for the same indication. This is the rule most likely to generate a claim denial that surprises billing teams. If a brain SPECT or FDG PET has already been done for the same indication, a repeat scan is not covered — with two narrow exceptions. First, if the patient has experienced significant changes in the scope or severity of cognitive decline and meets all qualifying criteria again, the indication can be considered different. Second, if a prior SPECT result was inconclusive or difficult to interpret due to inadequate technology, a follow-up FDG PET may be covered — but not until one year has passed from the original scan.

7. Referring and billing providers have documented the full evaluation in the medical record. This isn't just a clinical requirement. It's a billing requirement. CMS expects the date of symptom onset, the date of formal dementia diagnosis, all evaluation components, the basis for suspecting FTD, and the clinical judgment that the diagnosis remains uncertain — all of it documented and available in the beneficiary's medical record.

Medical Necessity Is the Whole Ballgame Here

FDG PET billing for dementia lives and dies on medical necessity documentation. Every one of those seven criteria maps to something that needs to be in the chart before you submit a claim. If your workflow depends on the ordering physician doing that documentation correctly without prompting, you're going to see denials.

Build a pre-authorization and pre-billing checklist that maps directly to criteria one through seven. This is not optional process improvement — it's the difference between payment and a denial you'll spend weeks appealing.

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CMS FDG PET Exclusions and Non-Covered Indications

The CMS FDG PET coverage policy under NCD 288 is explicit about what does not qualify for coverage in the dementia differential diagnosis pathway.

FDG PET is not covered when the diagnosis has already been clearly established through prior evaluation. The scan exists to resolve diagnostic uncertainty — not to confirm a diagnosis the physician already has.

FDG PET is not covered when a prior brain SPECT or FDG PET was already obtained for the same indication, unless the patient meets the re-scan exception criteria described above (significant clinical change plus one-year waiting period for SPECT, or inconclusive prior results).

FDG PET is not covered when the reading facility lacks the necessary nuclear medicine accreditation. Similarly, if the scan is not read by a qualified expert — a physician with experience in nuclear medicine, radiology, neurology, or psychiatry who has specific experience interpreting scans in dementia patients — coverage is at risk.

The clinical trial pathway has its own rules. FDG PET in a CMS-approved practical clinical trial is covered, but only for trials specifically focused on FDG PET's utility in diagnosing or treating dementing neurodegenerative diseases. A general dementia trial that includes FDG PET incidentally does not qualify.

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Coverage Indications at a Glance

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CMS FDG PET Billing Guidelines and Action Items 2026

The effective date is January 9, 2026. Here's what your billing team needs to do now.

1. Build a seven-point pre-scan documentation checklist and attach it to your FDG PET order workflow. Map each item directly to NCD 288's criteria. The checklist should capture: date of symptom onset, date of dementia diagnosis, evidence of six-plus months of documented cognitive decline, AAN-standard evaluation components, the evaluating physician's dementia expertise, the clinical basis for suspecting FTD, and confirmation that the diagnosis remains uncertain. Every FDG PET order for a dementia indication should clear all seven boxes before it goes to the scanner.

2. Audit your prior scan history before ordering. Before submitting any FDG PET claim for a dementia differential, confirm whether the patient has a prior brain SPECT or FDG PET on record for the same indication. If one exists, verify whether the patient has had a significant clinical change and whether one year has passed since the prior scan, if applicable. A claim denial because of a prior scan the billing team didn't know about is a very avoidable problem.

3. Confirm facility accreditation is current and documented. Nuclear medicine equipment accreditation is a hard coverage requirement under NCD 288. If your facility's accreditation is up for renewal, do not let it lapse. Document the accreditation status in your billing records. If you're billing on behalf of an outpatient facility, verify their accreditation before the January 9, 2026 effective date.

4. Document the reading physician's qualifications in the medical record. The scan must be interpreted by someone with experience in nuclear medicine, radiology, neurology, or psychiatry — and with specific experience reading these scans in the context of dementia. This qualification needs to be documentable, not just assumed. Include the reading physician's specialty and relevant experience in the report or a separate attestation.

5. Verify clinical trial enrollment separately before billing the trial pathway. If your facility participates in clinical trials involving FDG PET, confirm the trial has specific CMS approval for the FDG PET indication. The trial must be focused on FDG PET's utility in diagnosing or treating dementing neurodegenerative diseases. If you're unsure whether your trial qualifies, contact your compliance officer before submitting claims under the clinical trial pathway.

6. Confirm your prior authorization process accounts for NCD 288 requirements. Prior authorization requirements at the MAC level may layer on top of NCD 288's national coverage policy. Check with your Medicare Administrative Contractor to confirm whether prior auth is required for FDG PET in your region and whether additional documentation needs to accompany those requests.

7. Train your referring providers on what must be in the chart before they order. FDG PET billing for dementia fails at the referring physician's desk more often than anywhere else. If the ordering provider hasn't documented cognitive decline over six months, or hasn't documented the basis for suspecting FTD, the claim will fail. Send referring neurology and psychiatry practices a one-page summary of NCD 288's requirements before January 9, 2026.

If your practice has high FDG PET volume for dementia indications and you're not confident your current documentation process hits all seven criteria consistently, talk to your compliance officer before the effective date. The reimbursement exposure here is real, and post-payment audits on high-utilization imaging codes are common.

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CPT, HCPCS, and ICD-10 Codes for FDG PET Under NCD 288

Covered Codes

The updated NCD 288 policy document does not list specific CPT or HCPCS codes. This is a known limitation of this version of the policy data.

For FDG PET billing, your coding team should confirm the appropriate PET imaging CPT codes with your Medicare Administrative Contractor and cross-reference against your facility's current charge master. Do not assume the codes you're currently using are the right ones without that verification — especially if your coding conventions have not been reviewed since the prior version of NCD 288.

A Note on Code Assignment

The absence of specific codes in this NCD does not mean coding is discretionary. CMS expects FDG PET claims to be coded correctly according to current CPT guidelines. Incorrect code assignment — even when the clinical criteria are fully met — can trigger a claim denial or a post-payment audit. If you're uncertain about code selection for FDG PET in the dementia differential context, loop in your coding consultant or submit a question to your MAC before the January 9, 2026 effective date.

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