(2026) PET Scan CPT Codes Explained: 78811-78816, PI/PS & NCD

Quick Reference: PET Scan CPT Code Family

• Core Oncology PET Codes: 78811-78816 -- Select based on body region scanned and whether CT attenuation correction is performed concurrently.
• Most Commonly Billed: 78815 (PET/CT, skull base to mid-thigh) and 78816 (PET/CT, whole body) account for the vast majority of oncologic PET claims.
• Required Oncology Modifiers: PI (initial treatment strategy) or PS (subsequent treatment strategy) must appear on every FDG PET oncology claim for Medicare.
• Radiopharmaceutical Code: Always bill A9552 (FDG) on the same claim as the PET CPT code. Cardiac PET uses A9555 (Rb-82) or A9526 (N-13 Ammonia) with codes 78491/78492.
• 2025 Major Change: CMS now pays separately for diagnostic radiopharmaceuticals costing more than $630 per day under HOPPS -- a landmark change effective January 1, 2025.
• Non-Covered Indication Code: Bill G0235 when performing a PET scan for an indication not covered under NCD 220.6.

Positron Emission Tomography (PET) is one of the most powerful and clinically impactful imaging modalities in modern medicine, used to evaluate tissue metabolism in cancer, neurological disorders, and cardiac disease. Coding PET scans correctly is complex, involving a family of six primary CPT codes (78811-78816), additional codes for brain and cardiac studies, mandatory HCPCS radiopharmaceutical codes, Medicare modifier requirements, and National Coverage Determination (NCD) restrictions. A single billing error -- such as a missing PI/PS modifier or incorrect body region code -- can result in immediate claim denial or post-payment audit.

This guide covers every current CPT code, all Medicare NCD requirements, documentation standards, and coding scenarios needed to bill PET scans compliantly in 2026.

1. The PET Scan CPT Code Family: 78811-78816 Explained

The six primary oncologic PET codes are organized into two tiers: codes without a concurrently acquired CT (78811-78813) and codes with a concurrently acquired CT for attenuation correction and anatomic localization (78814-78816). Within each tier, the code is further determined by the body region scanned.

Codes 78811-78813: PET Without Concurrently Acquired CT

These codes describe PET imaging performed on a dedicated PET-only scanner, or when the CT portion performed on a combined PET/CT system is a separate, stand-alone diagnostic CT (i.e., acquired on a different piece of equipment or interpreted independently as a diagnostic study):

• 78811 -- Tumor imaging, PET; limited area (e.g., chest, head/neck, or any scan that does not extend from skull base to mid-thigh). Used when only one discrete body region is imaged.
• 78812 -- Tumor imaging, PET; skull base to mid-thigh. The standard field of view for most solid tumor oncology studies. This is the most appropriate code when the scan extends from the base of the skull down to the mid-thigh region but does not include the lower legs and feet.
• 78813 -- Tumor imaging, PET; whole body. Extends from the top of the head (vertex) to the feet or lower leg. Most commonly used for melanoma staging and restaging, where extremity involvement must be assessed.

Codes 78814-78816: PET/CT With Concurrently Acquired CT

These are the most commonly billed codes in clinical practice today. They describe integrated PET/CT systems where the CT is acquired at the same time, on the same machine, and is used specifically for attenuation correction and anatomic localization of the PET findings:

• 78814 -- Tumor imaging, PET with concurrently acquired CT; limited area. Mirrors 78811, but with the integrated CT component included. Used for single-region scans (e.g., chest-only PET/CT for lung cancer surveillance).
• 78815 -- Tumor imaging, PET/CT; skull base to mid-thigh. The workhorse of oncologic PET billing. The vast majority of solid tumor staging, restaging, and treatment response monitoring studies fall under this code.
• 78816 -- Tumor imaging, PET/CT; whole body. Reserved for cases requiring imaging from vertex to feet/lower extremities. Indicated for melanoma and other tumors with potential extremity involvement.

Critical Distinction: PET vs. PET/CT Code Selection: If the CT scan is performed concurrently on the same integrated PET/CT scanner and its primary purpose is attenuation correction and anatomic localization, use codes 78814-78816. If a truly diagnostic CT is performed separately and independently interpreted, you may report the PET code (78811-78813) plus the appropriate diagnostic CT code with modifier 59 or XU -- but only if performed on separate equipment per NCCI Policy Manual guidance effective January 1, 2018.

flowchart TD
    A[PET Scan Ordered] --> B{CT acquired concurrently<br/>on same integrated scanner?}
    B -->|Yes| C{Body region?}
    B -->|No / PET-only scanner| D{Body region?}
    C -->|Limited area| E[78814]
    C -->|Skull base to mid-thigh| F[78815]
    C -->|Whole body vertex to feet| G[78816]
    D -->|Limited area| H[78811]
    D -->|Skull base to mid-thigh| I[78812]
    D -->|Whole body vertex to feet| J[78813]
    E --> K{Oncology indication?}
    F --> K
    G --> K
    H --> K
    I --> K
    J --> K
    K -->|Yes, initial treatment| L[Append modifier PI + A9552]
    K -->|Yes, subsequent treatment| M{Scan number for this cancer?}
    K -->|No / Non-covered| N[Use G0235]
    M -->|1st-3rd scan| O[Append modifier PS + A9552]
    M -->|4th+ scan| P[Append modifiers PS + KX + A9552]

2. Brain PET (78608) and Cardiac PET Codes

Brain PET: CPT 78608 and 78609

• 78608 -- Brain imaging, PET; metabolic evaluation. Billed when FDG (A9552) is used to evaluate brain metabolism. Covered by Medicare for: (a) differential diagnosis of Alzheimer's disease (AD) vs. frontotemporal dementia (FTD) per NCD 220.6.13, and (b) brain tumor evaluation (must append modifier QR for tumor studies).
• 78609 -- Brain imaging, PET; perfusion evaluation. Used with perfusion tracers to assess regional cerebral blood flow. Less commonly billed and subject to strict MAC coverage criteria.

For oncologic brain tumor evaluation using 78608, providers must also include modifier QR on the claim and submit ICD-10-CM code Z00.6 on institutional claims. This code is also used for FDG PET in the determination of initial (PI) and subsequent (PS) treatment strategy for brain tumors. Note that 78608 requires a dedicated brain protocol and should NOT be reported when a skull-to-mid-thigh or whole-body protocol incidentally images the brain.

Cardiac PET Codes

The cardiac PET code family was significantly revised in 2020, when new combination codes and CT add-on codes were introduced:

• 78459 -- Myocardial imaging, PET; metabolic evaluation study (viability). Single study using FDG (A9552). Covered for myocardial viability assessment prior to revascularization or following an inconclusive SPECT (NCD 220.6.8).
• 78429 -- Myocardial imaging, PET; metabolic evaluation with concurrently acquired CT. Same as 78459, but includes integrated CT for attenuation correction.
• 78491 -- Myocardial imaging, PET; perfusion, single study at rest or stress. Uses Rubidium-82 (A9555) or N-13 Ammonia (A9526). For CAD diagnosis or management when SPECT is inappropriate.
• 78430 -- Myocardial imaging, PET; perfusion, single study with concurrently acquired CT. The PET/CT version of 78491.
• 78492 -- Myocardial imaging, PET; perfusion, multiple studies at rest and stress. The most comprehensive cardiac PET, paired with A9555 or A9526.
• 78431 -- Myocardial imaging, PET; perfusion, multiple studies at rest and stress, with concurrently acquired CT. PET/CT version of 78492.
• 78432 / 78433 -- Combined metabolic and perfusion PET (without/with concurrent CT). Dual radiotracer studies combining FDG viability with rubidium/ammonia perfusion imaging.
• +78434 -- Add-on: Absolute Quantitation of Myocardial Blood Flow (AQMBF). Report in addition to 78431 or 78492 when absolute quantification of myocardial blood flow is performed.

3. Radiopharmaceutical Billing: HCPCS Codes and the 2025 Unbundling Rule

Every PET scan requires a radiopharmaceutical tracer, and billing the correct HCPCS tracer code on the same claim as the PET CPT code is mandatory under CMS rules. Failure to include the tracer code is a leading cause of PET claim rejections.

Required Tracer Codes by Procedure

• A9552 -- Fluorodeoxyglucose F-18 (FDG), diagnostic, per study dose, up to 45 millicuries. The universal FDG tracer. Required with CPT codes 78459, 78608, and 78811-78816 for all oncology and brain studies.
• A9555 -- Rubidium Rb-82, diagnostic, per study dose, up to 60 millicuries. Used exclusively with cardiac perfusion PET codes 78491, 78492, 78431, 78432, 78433.
• A9526 -- Nitrogen N-13 Ammonia, diagnostic, per study dose, up to 40 millicuries. Alternative cardiac perfusion agent. Used with 78491, 78492, 78431-78433.
• A9580 -- Sodium Fluoride F-18 (NaF), diagnostic, per study dose, up to 30 millicuries. Used for bone metastasis PET imaging with codes 78811-78816 under CED/clinical trial (modifier Q0 required). PI or PS modifier must also be appended; modifier KX is required on professional component claims.
• A9597 / A9598 -- Radiopharmaceutical, diagnostic, Not Otherwise Classified (NOC). For newer proprietary tracers without a dedicated HCPCS code. The claim must include the drug name, total dosage, and invoice amount in field 19 of the CMS-1500 form.

Newer Proprietary Tracer HCPCS Codes (Non-FDG)

For oncologic imaging with proprietary agents, local MACs determine coverage for their FDA-approved labeled indications. Key codes include A9586 (Florbetapir F-18, amyloid brain imaging), A9599 (Piflufolastat F-18/PYLARIFY, PSMA prostate cancer PET), and A9588 (Fluciclovine F-18/Axumin, prostate recurrence PET). Always verify MAC-specific LCDs for coverage of these agents.

Major 2025 Change: Radiopharmaceutical Unbundling Under HOPPS

Effective January 1, 2025 -- CMS HOPPS Final Rule: In a landmark decision, CMS began paying separately for diagnostic radiopharmaceuticals with per-day costs exceeding $630 under the Hospital Outpatient Prospective Payment System (HOPPS). Previously, virtually all diagnostic radiopharmaceuticals were bundled as "supplies" into the PET procedure payment, often resulting in hospitals receiving inadequate reimbursement for high-cost newer tracers. Under the new policy, high-cost tracers (such as PSMA agents and amyloid PET agents) are now reimbursed on top of the base PET procedure payment, using Mean Unit Cost (MUC) methodology. This change has significantly improved the financial viability of advanced PET imaging at hospital outpatient departments and is expected to expand patient access. The $630 threshold will be updated annually using the Producer Price Index for Pharmaceutical Preparations.

Invoice Reporting Requirement

For radiopharmaceuticals billed under the Medicare Physician Fee Schedule (MPFS) at physician offices and IDTFs, the invoice cost for the radiopharmaceutical must be reported in Block 19 of the CMS-1500 form (or electronic equivalent Loop 2400 Segment NTE02) in the format: INV. $00.00. Claims submitted without invoice information are subject to rejection by First Coast and other MACs.

4. Medicare Coverage: NCD 220.6 and PI/PS Modifier Requirements

Medicare coverage for PET scans is governed by a series of National Coverage Determinations (NCDs) under Publication 100-03, Chapter 1, Part 4, Section 220.6. Key sub-sections include:

• NCD 220.6.1 -- PET for Perfusion of the Heart (Myocardial Viability)
• NCD 220.6.8 -- PET for Myocardial Perfusion
• NCD 220.6.13 -- FDG PET for Dementia and Neurodegenerative Diseases (AD vs. FTD)
• NCD 220.6.17 -- FDG PET for Oncologic Conditions (the primary NCD governing cancer PET billing)
• NCD 220.6.19 -- FDG PET for Infection and Inflammation
• NCD 220.6.20 -- Beta-Amyloid PET in Dementia and Neurodegenerative Disease

A critical principle: unless a specific use of PET is listed as covered in one of these NCDs, Medicare will not cover it (with the exception that local MACs may cover new proprietary radiopharmaceuticals for their FDA-labeled oncologic indications per a 2013 CMS ruling). Any PET scan performed for a non-covered indication should be billed using G0235.

The PI and PS Modifiers: Required on Every Oncologic FDG PET Claim

For all FDG PET oncology claims (CPT codes 78608, 78811-78816 billed with A9552 for cancer indications), CMS requires one of two mandatory modifiers effective for dates of service on or after April 6, 2009:

• PI -- Initial Treatment Strategy: The scan is being performed to inform the initial treatment plan for a tumor that is biopsy-proven or strongly suspected of being cancerous based on other diagnostic testing. Medicare covers PET scans under modifier PI to determine whether a patient is an appropriate candidate for an invasive diagnostic or therapeutic procedure, identify the optimal anatomic location for biopsy, or stage the extent of disease.
• PS -- Subsequent Treatment Strategy: The scan is being performed to guide anti-tumor treatment after completion of initial therapy. Medicare covers up to three PET scans per cancer indication under modifier PS without additional documentation. A fourth or subsequent PS-billed scan for the same cancer diagnosis requires modifier KX appended to the claim to certify that medical necessity criteria have been met and documentation is on file.

Denial Alert -- Modifier PS Frequency Limit: Claims for more than 3 FDG PET scans for subsequent treatment strategy (modifier PS, same cancer diagnosis) submitted without modifier KX will be auto-denied by MACs with CARC 96 and RARC N435. The KX modifier certifies that the physician has documented why additional scans beyond the standard allowance are medically necessary for that specific cancer diagnosis.

Clinical Trial Coverage: Modifiers Q0 and Q1

When PET scans are performed as part of a CMS-approved clinical trial or under Coverage with Evidence Development (CED):

• Q0 -- Investigational clinical service in an approved clinical research study.
• Q1 -- Routine clinical service provided in an approved clinical research study.

Institutional claims must also include diagnosis code Z00.6 and condition code 30 for clinical trial services. This applies, for example, to NaF-18 (A9580) bone metastasis PET imaging, which is only covered in an approved clinical research study.

5. Covered Oncologic Indications and Common ICD-10 Codes

The following cancers are among those covered under NCD 220.6.17 for both initial (PI) and subsequent (PS) treatment strategies for FDG PET imaging using codes 78811-78816 and 78608:

• C34.xx -- Malignant neoplasm of bronchus and lung (NSCLC). The most commonly billed oncologic PET indication. Covered for diagnosis, staging, restaging, and treatment response assessment of non-small cell lung cancer. Note: Small cell lung cancer subsequent treatment strategy must be in an approved clinical trial (Q0 modifier).
• C50.xxx -- Malignant neoplasm of breast. Covered as an adjunct to standard imaging for staging patients with distant metastasis or restaging those with locoregional recurrence. Not covered for initial diagnosis or initial staging of axillary lymph nodes.
• C18.x / C19 / C20 -- Colorectal cancer. Covered for diagnosis, staging, and restaging.
• C81.xx-C86.xx -- Lymphoma (Hodgkin and Non-Hodgkin). Covered for staging and restaging. FDG PET is the standard of care for Hodgkin lymphoma assessment per NCCN guidelines.
• C43.xx -- Malignant melanoma. Covered; frequently justifies CPT 78816 (whole body) given the need to assess extremity metastases.
• C73 -- Malignant neoplasm of thyroid. Covered only for restaging of recurrent or residual follicular cell thyroid cancer after thyroidectomy and radioiodine ablation, with serum thyroglobulin >10 ng/mL and a negative I-131 whole body scan.
• C61 -- Malignant neoplasm of prostate. FDG PET has limited utility here; however, PSMA PET (A9599 + 78815/78816) is covered by many MACs per LCD for staging and restaging of prostate cancer using fluciclovine (A9588) or piflufolastat F-18 (A9599).
• C22.0 -- Hepatocellular carcinoma; C25.xx -- Pancreatic cancer. Coverage per MAC LCD discretion; check local policies.
• G30.9 -- Alzheimer's disease (unspecified); G31.09 -- Frontotemporal dementia. Covered for FDG PET brain imaging (78608) for differential diagnosis of AD vs. FTD under NCD 220.6.13, subject to specific clinical criteria. Use G30.9 and G31.9 per current NCD guidance.

Cervical Cancer Exception: There is no Medicare payment for the initial diagnosis of cervical cancer with PET. Cervical cancer is covered only for the detection of pre-treatment metastases (staging) in newly diagnosed cases when conventional imaging is negative for extra-pelvic metastasis. All other cervical cancer PET uses are Coverage with Evidence Development (CED) only.

6. Audit-Proof Documentation Standards

PET scans are a perennial focus of Medicare audits and Recovery Audit Contractor (RAC) reviews. The ordering physician's documentation must support both the clinical indication and the specific modifier used. Vague orders and incomplete medical records are the primary drivers of post-payment recoupment.

The following documentation elements should be present in the referring/ordering physician's record for every PET scan claim:

• Pathological or Clinical Diagnosis: The medical record must clearly document that the tumor is biopsy-proven or "strongly suspected based on other diagnostic testing" (for PI modifier). For PS modifier, prior treatment history must be documented.
• Reason for the Study: Explicitly state whether the PET is for staging (PI), restaging (PS), or treatment response monitoring (PS). Vague language like "rule out metastasis" is inadequate without clinical context.
• Prior Imaging Results: Document what prior imaging (CT, MRI, bone scan) was performed and its results. For some indications (e.g., breast cancer, thyroid cancer), conventional imaging must precede or accompany the PET order.
• KX Modifier Documentation (4th+ PS scan): For the fourth or subsequent FDG PET scan under a PS modifier, the physician must document in detail why the additional scan is medically necessary -- specifically, how the scan results will change management of the patient's anti-tumor treatment strategy.
• Glucose Level: All PET procedures include a finger-stick blood glucose level as part of the procedure. This is bundled into the PET code and should NOT be billed separately using CPT 82948 or 82962.
• Radiologist Interpretation Report: Must identify the specific CPT code used, the body region imaged, the tracer administered, the clinical indication, comparison imaging reviewed, and detailed findings and impression.

Example of Compliant vs. Non-Compliant Documentation

7. Modifier Usage: PI, PS, KX, Q0, Q1, 26, TC

Modifier 26 (Professional Component) and TC (Technical Component)

When the interpreting physician (radiologist or nuclear medicine physician) and the facility billing the technical component are separate entities, the claim must be split:

• Append modifier 26 to the PET CPT code when billing for the radiologist's professional interpretation only (e.g., 78815-26).
• Append modifier TC when billing for the technical component (equipment, staff, radiopharmaceutical) only -- typically billed by the facility or IDTF.
• When a physician practice owns and operates its own scanner and the same entity performs and interprets the study, bill the global code without a modifier.

Modifier 59 / XU (Distinct Procedural Service)

Used to unbundle a diagnostic CT from a PET study when a truly separate, full diagnostic CT is performed on the same day. Per NCCI Policy Manual, if the diagnostic CT is obtained on the same PET/CT integrated system for attenuation correction purposes, it cannot be separately billed. However, if performed on separate equipment with a separate diagnostic interpretation, the CT code may be reported with modifier 59 (or XU) appended to the CT code to indicate a distinct service.

Modifier KX

Required on the 4th and any subsequent FDG PET scan for PS-modifier oncologic studies with the same cancer diagnosis. Certifies that medical necessity documentation has been created and is maintained in the medical record. Also required on NaF-18 (A9580) bone metastasis PET claims for the professional component to confirm covered indication.

Modifier GC (Teaching Physician)

Required when a teaching physician supervises a resident's involvement in the PET scan interpretation. Certifies the teaching physician reviewed the images and participated in the key portions of the service.

8. Billing the Concurrent Diagnostic CT: NCCI Rules

This is one of the most frequently misunderstood aspects of PET/CT coding. The rules are:

• Attenuation correction CT only (i.e., low-dose, non-contrast CT used purely to correct and localize PET data): This CT is bundled into CPT codes 78814-78816. It cannot be billed separately. Period.
• Full diagnostic CT performed concurrently on the same PET/CT machine (same equipment): Per the 2018 NCCI Policy Manual update, the provider may report PET using codes 78811-78813 (the non-CT codes) and add the appropriate diagnostic CT code with modifier 59 or XU on the CT -- but only when the CT dataset is being acquired for diagnostic purposes beyond mere PET localization.
• Full diagnostic CT performed on entirely separate equipment on the same day: Bill the appropriate PET/CT code (78814-78816) separately from the CT code; use modifier 59 or XU on the CT code. This scenario is uncommon in modern integrated facilities.

Common Billing Error: Billing both a PET/CT code (78815 or 78816) AND a separate CT code (e.g., 74178) for the same integrated PET/CT study -- without modifier 59 -- is a known NCCI edit violation and a top cause of post-payment audits and recoupments.

9. OPPS vs. Physician Fee Schedule: Site-of-Service Billing

The payment setting significantly affects how PET scans are reimbursed:

Hospital Outpatient Department (HOPPS / OPPS)

PET scans performed in hospital outpatient departments are paid under the OPPS Ambulatory Payment Classification (APC) system. Key features for 2025-2026:

• Radiopharmaceuticals with per-day costs above $630 are now paid separately using Mean Unit Cost (MUC) methodology (effective 1/1/2025).
• Radiopharmaceuticals below the $630 threshold remain packaged into the APC payment for the associated procedure and are not separately reimbursed.
• The PET procedure itself is assigned to an APC based on the CPT code billed. National 2024 OPPS payments were approximately $1,354-$1,492 for limited-area codes (78811/78814) and higher for whole-body scans. 2025 rates reflect annual OPPS updates.
• Hospitals must bill the radiopharmaceutical with the appropriate HCPCS code and revenue code 0343 (diagnostic radiopharmaceutical).

Physician Office / Independent Diagnostic Testing Facility (IDTF)

PET scans in non-hospital settings are paid under the Medicare Physician Fee Schedule (MPFS):

• Technical component (TC) payment is determined by a fee schedule, often capped at the OPPS technical component rate.
• Professional component (26) payment for interpretation is made under the MPFS at resource-based relative values (RVUs).
• Radiopharmaceutical reimbursement is based on invoice cost -- the actual cost paid by the facility for the drug. The invoice amount must be reported on the claim (Block 19 of CMS-1500). The radiopharmaceutical is paid separately in the physician office setting (not bundled), though payment methodology varies by MAC.

10. Complex Coding Scenarios

Scenario 1: Initial Staging of NSCLC -- Skull Base to Mid-Thigh PET/CT

Patient: 67-year-old male with biopsy-proven Stage IIIA right upper lobe adenocarcinoma (C34.11). No known distant metastases on CT. PET/CT ordered prior to initiation of concurrent chemoradiation to assess nodal staging.

Equipment: Integrated PET/CT scanner; CT acquired for attenuation correction and localization only (low-dose, non-contrast).

Coding: 78815-PI + A9552 (bill on same claim).

Rationale: PET/CT with concurrent CT (78815), skull base to mid-thigh field of view. PI modifier because this is an initial treatment strategy scan for biopsy-proven cancer. FDG tracer A9552 billed on same claim. No separate CT code may be billed since CT is for attenuation correction only.

Scenario 2: Lymphoma Treatment Response (4th Scan) -- KX Modifier Required

Patient: 55-year-old female with diffuse large B-cell lymphoma (C83.30). This is her 4th FDG PET scan since diagnosis. She completed R-CHOP and consolidation radiation. Now on maintenance therapy; oncologist needs PET to assess whether CR is maintained before changing to watchful waiting.

Coding: 78815-PS-KX + A9552.

Rationale: PS modifier for subsequent treatment strategy. KX modifier required because this is the 4th scan under PS for the same cancer diagnosis (C83.30). Medical record must document the specific clinical reason this additional scan is necessary for treatment decision-making. Without KX, the claim auto-denies.

Scenario 3: Melanoma Staging -- Whole Body PET/CT

Patient: 48-year-old male with Stage IIC cutaneous melanoma (C43.61) of the right calf. Wide local excision performed. CT shows no thoracic or abdominal metastases, but lower extremity nodes are equivocal.

Coding: 78816-PI + A9552.

Rationale: Whole body code (78816) is required -- not 78815 -- because melanoma staging requires imaging to the feet to rule out distal extremity metastases. PI modifier for initial treatment strategy. Using 78815 would be incorrect because the field of view only extends to mid-thigh and would miss lower leg lesions.

Scenario 4: Cardiac PET for CAD Evaluation -- Rest/Stress

Patient: 72-year-old female with atypical chest pain and a known left bundle branch block (making stress ECG non-interpretable). Cardiologist orders PET myocardial perfusion imaging at rest and pharmacologic stress.

Coding: 78492 + A9555 (Rubidium-82) or A9526 (N-13 Ammonia), depending on tracer used. If concurrent CT for attenuation correction, use 78431 instead.

Rationale: Covered under NCD 220.6.8 for diagnosis of CAD. 78492 is the multi-study (rest + stress) code. Tracer selection depends on what your facility uses -- Rb-82 (A9555) is more common; N-13 Ammonia (A9526) requires an on-site cyclotron. PI/PS modifiers do NOT apply to cardiac PET -- these are oncology-only modifiers.

Scenario 5: Alzheimer's vs. FTD Differential Diagnosis -- Brain PET

Patient: 78-year-old male with progressive cognitive decline (G31.9). Clinical presentation is atypical; neurologist cannot distinguish AD from FTD. Neuropsychological testing inconclusive. FDG PET brain requested.

Coding: 78608-Q1 + A9552. If in a CED clinical study: append Q0 or Q1; institutional claims add Z00.6 and condition code 30.

Rationale: NCD 220.6.13 covers FDG PET brain for this specific differential diagnosis. Note: this coverage is strictly limited -- FDG PET is NOT covered for general dementia workup. The clinical record must document that all routine workup has been completed and the differential specifically narrows to AD vs. FTD. Use G30.9 for Alzheimer's disease diagnosis and G31.9 for FTD per current NCD guidance.

11. Full PET Scan CPT Code Comparison Table