Tear out: Your FESS anatomy crosswalk reveals capturables Trace your otolaryngologist's work and capture functional endoscopic surgery (FESS) procedures and related nasal and concha bullosa work using this diagram. If you can't keep track of where your surgeon is working, you could overlook separately codeable sinus procedures. To leave no dollars on the table, keep this anatomy sheet with CPT and ICD-9 crosswalk handy.