Otolaryngology Coding Alert

Question: A patient was scheduled for functional endoscopic sinus surgery (FESS), but once the procedure began the surgeon discovered the patient had a large mass growing from the sinus into the mouth. The otolaryngologist performed an open Caldwell-Luc (CL) antrostomy in order to access and remove all the polyps and masses. She entered the maxillary tissues through the gum line. How do we code the shift from FESS to something completely different?

Louisiana Subscriber

Answer: In this case, you would code the C-L with removal of tissue (31032, Sinusotomy, maxillary [antrotomy]; radical [Caldwell-Luc] with removal of antrochoanal polyps) and the appropriate FESS ethmoidectomy (either 31254, Nasal/sinus endoscopy, surgical; with ethmoidectomy, partial [anterior]; or 31255,... with ethmoidectomy, total [anterior and posterior]).

Remember, you may bill an endoscopic procedure performed on another sinus in addition to open maxillary antrostomy. The insurer may reduce payment for the ethmoidectomy to 50 percent following Medicare multiple procedure rules. Keep in mind that the open C-L procedure is a Column 1 code to both endoscopic maxillary sinus codes (31256, Nasal/sinus endoscopy, surgical, with maxillary antrostomy, and 31267, … with removal of tissue from maxillary sinus). So, although your surgeon may have performed a 31267 and then converted the endoscopic procedure to an open procedure, you may only bill for the open procedure, 31032.