Let me guess, was it Human or UHC? There are a couple of scenarios... 1) Did the other surgeon bill the same way? Did they use mod 62? If they did not use the modifier then they may have gotten paid already (full amount) They will need to submit a corrected claim. 2) Usually for this code there is a Neurosurgeon and an ENT surgeon. 3) I would check the op report to make sure that they did approach the op the same way as 62165.. 62165 is an endoscopic resection and 61548 is an open approach usually with microscope.