Question: The provider performed a debridement endoscopy (31237) at a one-month check-up visit following a 31255, 31267, 30140 and 30520. May I bill for the 31237 since this still qualifies as the postoperative period? Delaware Subscriber Answer: The global periods for the original procedures performed are as follows: In order to report 31237 (Nasal/sinus endoscopy, surgical; with biopsy, polypectomy or debridement (separate procedure)) within the postoperative period of code 30520, you will have to confirm that the debridement is entirely unrelated to the septoplasty. If you are unable to verify that the postoperative debridement is related to one of the surgeries with a global period of 0 days, then you should not consider billing 31237 separately. However, if there is documentation to support that the debridement is unrelated to the septoplasty, you may report 31237 with modifier 79 (Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period). It is recommended that the practice pre-certify the postoperative debridement when pre-certifying the surgery.