Fig. 3 Picture showing the details of intraoperative setting demonstrating that air flow through the nose can be limited by the use of the nose lid. a The microdrill is inserted through the left nostril and the nose lid adheres to its outer diameter. b The endoscope and suction tube are inserted through one nostril, i.e., the right, in two different slit cuts. c The endoscope is inserted through the right nostril while the microdrill in the left one, each of them in the relative slit cut