Radiology Coding Alert

If coding image postprocessing and 3-D rendering confuses you, join the club. But help is here. See what this radiology coding expert has to say about 3-D rendering and CTA.

Question: I understand that a CTA requires "image postprocessing." Is the 3-D rendering dictation sufficient to code a CTA, rather than a CT?

Tennessee Subscriber

Answer: The 3-D rendering dictation qualifies as "image postprocessing" for computed tomographic angiography (CTA).

Imaging postprocessing refers to CT dataset 2-D and 3-D reconstructions, says Melody Mulaik, MSHS, CPC, CPC-H, RCC, of Coding Strategies Inc. in Powder Springs, Ga.

The provider creates the 2-D reformatted images in multiple planes, and then can interpret, annotate and archive them as hard copy, electronic files or both, she says. The provider typically evaluates 3-D or volume-rendered reconstructions in multiple projections. The work of 3-D reformatting is quite extensive, usually performed on a separate workstation.

And you're right that one of the main differences between CT and a typical CTA is that CTA includes angiographic image reconstruction postprocessing and interpretation.

Example: A physician orders a CTA for a patient with a suspected pulmonary embolism using a multidetector-row CTA to visualize the vessels. The radiologist documents 3D rendering.

You should report 71275 (Computed tomographic angiography, chest [noncoronary], without contrast material[s], followed by contrast material[s] and further sections, including image postprocessing).