Question: Delaware Subscriber Answer: For standard colonoscopy, you would use 45381 (Colonoscopy, flexible, proximal to splenic flexure; with directed submucosal injection[s], any substance) for tattooing or any other type of injection, but you won't find an injection code within the family of codes for colonoscopy through a stoma. If the GI performs a colonoscopy via stoma and takes a biopsy, then you should report 44389 (Colonoscopy through stoma; with biopsy, single or multiple). Otherwise, bill 44388 (Colonoscopy through stoma; diagnostic, with or without collection of specimen[s] by brushing or washing [separate procedure]) for a diagnostic procedure. You would need to use the "unlisted" code 44799 (Unlisted procedure, intestine) for the tattooing portion of the colonoscopy via stoma procedure. The added fee of less than 0.5 RVUs is probably not worth the hassle of submitting all the info needed for an unlisted code claim.