Radiology Coding Alert

Question: Is it appropriate to report both a CT and CTA of the same anatomic area performed on the same date?

West Virginia Subscriber

Answer: Typically, charging for both CT and CTA exams of the same anatomic area on the same date is not appropriate. You should report the CTA alone.

CCI support: The Correct Coding Initiative (CCI) edits bundle many CT and CTA codes for the same anatomic areas. For example, CCI bundles CT codes 70450-70470 (Computed tomography, head or brain ...) into CTA code 70496 (Computed tomographic angiography, head, with contrast material[s], including noncontrast images, if performed, and image postprocessing). These edits have a modifier indicator of "1," which means you may override them by appending a modifier to the CT code when appropriate.

Rationale: Acquiring CTA data involves taking a few noncontrast images for calibration and identification followed by a full set of with-contrast CT data, according to the American College of Radiology (ACR) Radiology Coding Source (May-June 2003). CTA also involves reformatting the images (specifically 3D angiographicreconstruction post-processing), as well as interpreting the source images and the reconstructions.

Exception: Separately reportable same-day CTs and CTAs should be rare, but occasionally CT findings "will raise clinical questions that require performance of a CTA on the same day," the ACR article indicates.

For example, suppose a patient has a CT for severe abdominal pain. The radiologist finds a tumor in the head of the pancreas, so the treating physician orders a CTA performed the same day "to evaluate the vascular invasion by the tumor." The radiologist performs and interprets a subsequent CTA, involving a new data acquisition. "In this scenario, although both procedures are performed during the same session or on the same day, the CT and CTA are separate and distinct procedures that use separate data sets and, therefore, are coded separately," the article states.

Experts warn: Before you code a CT and CTA for the same date, be sure both tests:

• Have an order from the treating physician

• Are medically necessary

• Are documented separately and completely.