Optimum Height From the Roof of the Choana for Seeking the Sphenoid Ostium

Abstract

In conclusion, under endoscopic view, the sphenoid sinus ostium can be safely probed between 13.3 mm (the minimum skull base height) and 5.7 mm (the minimum sphenoid sinus ostium height) distance upward from the choana, but determining the height of the sphenoid sinus ostium preoperatively on CTs for each patient separately will increase the chance of success in probing the sphenoid sinus.