METHODS: The MS of 5 fresh-frozen cadavers were sequentially dissected. Irrigation was evaluated with a squeeze bottle (SB) in different head positions and using different volumes of fluid. Surgical reach and visualization were examined using common sinus instruments and different angled endoscopes. A disease simulation was also performed to check for residual debris after instrumentation and irrigations.

RESULTS: Irrigation penetration improved as antrostomy size increased (p < 0.0001), with a significant difference observed between the extended procedures and MMA. The effect of the volume was significant for SB (p < 0.0001) but head positions appeared irrelevant (p = 0.613). Overall visualization improved for Mega-A and EMMA. A similar trend was seen for the reach of the instruments to all sinus wall subsites. EMMA facilitated the most removal of "sinus disease" in the disease simulation model when compared with both MMA and Mega-A, due to its reach of the anteroinferior aspects of the maxillary sinus.

METHODS: Consensus on a novel endoscopic sphenoid surgery classification system by running the Delphi procedure with 16 rhinology experts from around the world.

RESULTS: Four Delphi rounds were required to reach a consensus on all stages of the classification. The average percentage of agreement on the stages of classification progressively increased from 70.83% in the first round to 87.68% in the last round. The rejection rates continuously decreased from 8.81% in the first round to 4.44% in the last round. The classification system was developed as follows: stage 1, presphenoid surgery; stage 2A, partial sphenoidotomy; stage 2B, complete sphenoidotomy; stage 2C, transpterygoid sphenoidotomy; stage 3A, Rostral sphenoidectomy; and stage 3B, extended sphenoid drill-out.