Radiology Coding Alert

Plus: Learn how duplex scan coding hinges on a set of specific terms.

Depending on a patient’s medical diagnosis, a provider might find it necessary to order a renal Doppler scan alongside a retroperitoneal ultrasound.

Challenge: While radiologists regularly perform these two procedures together, coders often struggle to properly identify these procedures as they are documented in the physician’s dictation reports. However, deciphering the dictation to determine the correct procedural codes is only half the battle. As you will see, knowing when and where to incorporate modifier 59 (Distinct procedural service) is equally fundamental to the coding process.

Check out these tips for a better analysis of the provider’s dictation reports.

Start with the Technique, Move to Findings

When making sure the dictation report includes all the necessary features to code for a duplex scan, you’ll first want to turn your attention to the technique. For code 93975 (Duplex scan of arterial inflow and venous outflow of abdominal, pelvic, scrotal contents and/or retroperitoneal organs; complete study), you’ll be looking for a technique that resembles the following:

“Complete renal real-time scan with image documentation. Renal vessels and abdominal aorta are evaluated color-flow and spectral waveform analysis Doppler.”

Whether the duplex scan is limited or complete, you will want to make sure that the provider documents the terms gray scale imaging, spectral analysis, and color Doppler flow.

“Depending on the provider, you may come across words that you can use interchangeably with a term like ‘spectral,’” adds Lindsay Della Vella, COC, medical coding auditor at Precision Healthcare Management in Media, Pennsylvania. “You will find that this rule applies to numerous different terms found in a duplex scan dictation report. For example, you may consider terms such as ‘wave’ or ‘waveform,’ ‘resistance,’ ‘pulse,’ ‘RI,’ ‘resistive index,’ and ‘flow velocity’ as one in the same with ‘spectral analysis.’”

Best bet: “Make sure the physician includes one of these terms in addition to ‘color flow’ AND ‘grey scale Doppler’ to support the coding of a duplex scan,” Della Vella reiterates. If you cannot identify these three terms, send the report back to the provider for review.

Remember: In some cases, you may find some of these terms in the findings and/or technique portions of the note. “Ideally, the provider will include each of these three parameters in both the technique and the body of the report,” explains Barry Rosenberg, MD, chief of radiology at United Memorial Medical Center in Batavia, New York. “It is important that the provider elaborates on each of these three technical aspects in the findings for compliance purposes,” relays Rosenberg. For example, your provider might report the following in the body of the report:

“The main renal vein is patent and demonstrates a normal waveform.”

In this example, you may use the term “waveform analysis” interchangeably with “spectral analysis.”

Know your Anatomical Criteria

For both retroperitoneal ultrasounds and duplex scans, you’ll want to make sure that the dictation report documents all the appropriate anatomical criteria. For instance, in order to meet the criteria to bill out for a complete retroperitoneal ultrasound, you need to make sure your provider is documenting each required organ. The four organs necessary to reach code 76770 (Ultrasound, retroperitoneal [eg, renal, aorta, nodes], real time with image documentation; complete) are:

• Kidneys,
• Abdominal aorta,
• Common iliac artery origins, and
• Inferior vena cava.

Caveat: If clinical history references a history of urinary tract pathology, your provider may bypass this set of criteria and only report on the kidneys and urinary bladder.

The rules for coding limited versus complete abdominal/pelvic/retroperitoneal duplex scans are slightly different. According to the American Academy of Radiology (ACR), the coding of a complete duplex scan does not hinge on the number of organs the physician examines. On the contrary, the ACR explains that 93975 “can be used whether single or multiple organs are studied. It is a “complete” procedure in that all major vessels supplying blood flow (inflow and outflow, with or without color flow mapping) to the organ are evaluated.”

On the other hand, if the exam does not meet these requirements, you will want to apply the limited code 93976 (Duplex scan of arterial inflow and venous outflow of abdominal, pelvic, scrotal contents and/or retroperitoneal organs; limited study).

Rely on Modifier 59

In situations where your physician performs a 76770 and 93975 together, you will want to confirm that there is a clinical indication as to why the physician orders the duplex scan alongside the ultrasound. The medical necessity supporting the order of each exam does not need to differ in order for you to bill these procedures together.

When it comes to National Correct Coding Initiative (NCCI) edits, you will see that NCCI classifies 76770 as the column 2 code, requiring an overriding modifier in order to bill with 93975. Assuming that the documentation and medical necessity supports both procedures, you will add modifier 59 to 76770. The same rules apply for codes 76775 (Ultrasound, retroperitoneal [eg, renal, aorta, nodes], real time with image documentation; limited) and 93976 (Duplex scan of arterial inflow and venous outflow of abdominal, pelvic, scrotal contents and/or retroperitoneal organs; limited study).