Radiology Coding Alert

PS – remember to append treatment stage modifiers to your CPT^® codes.

Physicians order positron emission tomography (PET) scans to diagnose several conditions, including cancer. As a radiology coder, it’s your responsibility to know how to accurately code the procedure, tracer drugs, and append any appropriate modifiers to ensure your radiology practice receives proper reimbursement.

Get to know PET scans and uncover the complexities to ensure your code assignments are correct.

Understand the PET Scan Types

According to Chapter 13 of the Medicare Claims Processing Manual, PET scans are covered when detecting the stage of, restaging, and monitoring cancers, in addition to making the initial diagnosis. Radiologists may perform PET scans alone or in conjunction with a computed tomography (CT) scan, which is also known as a PET/CT scan or a PET/CT fusion.

With the right knowledge, you can overcome hurdles to correctly report a PET scan for reimbursement. “Diagnostic radiology coders face several challenges when coding PET scans, both in terms of selecting the appropriate CPT^® code and accurately identifying the specific radiopharmaceutical used in the scan,” says Laura Manser, CPC, CEMC, CPMA, CIRCC, RCC, coding manager of PBS – Radiology Business Experts in Reno, Nevada.

Familiarize Yourself With the PET and PET/CT Codes

One factor that affects your CPT^® code selection involves the extent of the scan. When you know what body areas the radiologist is examining, you can easily determine the correct PET scan type to code.

“PET scans are in the code set for the body part being scanned. You should review the procedure described within the radiology report documentation to verify the body part scanned and if the scan is a limited or complete exam,” says Sarah Watt, CPC, CEMC, coding supervisor of Acclara in Seattle, Washington. Limited examinations cover one or multiple areas of the body, but not the entire human body, whereas a complete exam, better known as a “whole body,” images the patient’s entire body from head to toe.

You’ll choose from the following codes for singular PET whole-body or limited scans:

• 78811 (Positron emission tomography (PET) imaging; limited area (eg, chest, head/neck))
• 78812 (… skull base to mid-thigh)
• 78813 (… whole body)

Alternatively, you’ll appoint one of the following codes for PET scans with concurrent CT scans:

• 78814 (Positron emission tomography (PET) with concurrently acquired computed tomography (CT) for attenuation correction and anatomical localization imaging; limited area (eg, chest, head/neck))
• 78815 (… skull base to mid-thigh)
• 78816 (… whole body)

Each of the codes in the 78811-78816 range are designated for procedures that image the body to detect, locate, and estimate the size of cancer cells or tumors in the patient.

When you examine the code descriptors, you’ll notice the code ranges are separated not only by imaging modality, but whether the scans are limited or complete. “To determine the correct code to use, it is important to carefully review the documentation provided by the radiologist, paying close attention to the extent of the anatomical coverage and any other procedures or imaging performed,” Manser says.

For example, the documentation may give the impression of a whole body scan when in reality, the provider performed a scan only from the skull to the mid-thighs.

Examine the following documentation examples:

• Whole body PET scan is performed in three planes from the skull base to the mid-thighs.
• Delayed whole body PET/CT fusion scan is performed in three planes from the skull base to the mid-thighs.

In both cases, the phrases “whole body” and “from the skull base to the mid-thighs” are included in the documentation. You’ll end up using 78812 and 78815, respectively, to code these procedures. However, “in cases where there is uncertainty about which code to use, coders should consult with the radiologist to ensure accurate coding for appropriate reimbursement,” Manser adds.

Brain scans: A radiologist may perform a PET scan of the patient’s brain to examine how the brain is functioning. In that case, you won’t report 78811 for a limited head scan. Why? The CPT^® code set Radiology section features a Nuclear Medicine category with a Nervous System subsection of codes, which include the following:

• 78608 (Brain imaging, positron emission tomography (PET); metabolic evaluation)
• 78609 (… perfusion evaluation)

Each code is designated for a different evaluation. You’ll assign 78608 if the radiologist performs a PET scan to assess information on the brain’s metabolism, which includes glucose, oxygen, and drug metabolism. You’ll assign 78609 if the provider performs a PET scan to study the brain’s function and how well blood is flowing to the brain.

Remember to Report Radiopharmaceuticals

In addition to choosing the CPT^® code for correct type of PET scan, you’ll need to assign the correct radiopharmaceutical tracer HCPCS Level II code to ensure accurate coding and reimbursement. “The reporting of the correct HCPCS Level II code can be ensured if coders first review the radiology report or physician’s order to identify the specific radiopharmaceutical used in the scan,” Manser says.

The HCPCS Level II code set contains several radiopharmaceutical types, but the two commonly used for PET scans include:

• Technetium Tc-99m, coded with A9510-A9512 and A9520-A9521 (Technetium Tc-99m …)
• Fluorodeoxyglucose (FDG), coded with A9552 (Fluoro­deoxyglucose F-18 FDG, diagnostic, per study dose, up to 45 millicuries)

For correct code selection, the experts Radiology Coding Alert spoke with recommend reviewing the dosage in the documentation. “Adding the correct number of units per the documentation is important for coding. These radiopharmaceuticals are measured in millicuries, which may be an unfamiliar unit of measure to new coders,” Watt says.

Payer policies: Of course, you should review your individual payer policies to see how they want radiopharmaceuticals to be reported, as well as which tracers will be reimbursed.

Mind the modifiers: Additionally, you’ll need to append an appropriate HCPCS Level II modifier to your respective PET or PET/CT CPT^® code. The modifiers you’ll use will depend on the procedure, and include:

• PI (Positron emission tomography (pet) or pet/computed tomography (ct) to inform the initial treatment strategy of tumors that are biopsy proven or strongly suspected of being cancerous based on other diagnostic testing)
• PS (Positron emission tomography (pet) or pet/computed tomography (ct) to inform the subsequent treatment strategy of cancerous tumors when the beneficiary’s treating physician determines that the pet study is needed to inform subsequent anti-tumor strategy)

You’ll append PI to procedure codes that the provider uses to plan the initial treatment strategy. For subsequent treatment strategies, you’ll append PS to your appropriate CPT^® code.