I am assuming that the patient's colon had been previously resected and an ileoanal anastomosis was created. Given the altered anatomy, I guess you could use an unlisted code, but if this was a transanal endoscopy, then the procedure is no different than work involved with an anoscopy or proctosigmoidoscopy. Based on your description, I would consider 45303, proctosigmoidoscopy with dilation, if the scope was inserted about the same distance as required to examine the rectum and sigmoid colon (in a patient with normal anatomy), or I would code 46604, anoscopy with dilation, if the scope did not go a significant distance beyond the anastomosis. Which scope was used for the procedure: an anoscope or a rigid sigmoidoscope?
Randy Kautz
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