Gastroenterology Coding Alert

Question: One of our physicians performed a colonoscopy on a Medicare patient with ulcerative colitis (no biopsies taken). The report states, “Chromoendoscopy was performed using methylene blue.” What is the procedure? Is there another CPT^® code besides 45378 that I can use?

Pennsylvania Subscriber

Answer: Chromoendoscopy, also called chromoscopy, is a procedure involving the topical application of stains or dyes at the time of endoscopy to enhance tissue characterization, differentiation, or diagnosis. Sometimes, chromoendoscopy is confused with endoscopic tattooing, which involves the injection of a long-lasting pigment such as India ink into the tissue for future localization.

In chromoendoscopy, methylene blue or other dyes are used to stain cells in the small bowel, colon, and intestinal metaplasia. Chromoendoscopy has no procedure code associated with it. When completed along with a colonoscopy, the chromoendoscopy may be considered incidental to the procedure, since it is only a topical application. You may use the procedure code 45399 (Unlisted procedure, colon) for this service. You should submit documentation along with the claim and have your provider draft a letter of medical necessity to fully explain the procedure and why it was needed. However, most payers do not recognize this for extra payment because the extra time is usually not substantially greater than the base colonoscopy. Another option is to bill with modifier 22 (Increased procedural services) and follow the process outlined earlier in this issue.