Revision 9 for 'Paranasal sinuses'All Revisions
The paranasal sinuses consists of, usually, four paired air-filled spaces. They have several functions of which reducing the weight of the head is the most important. Other functions are air humidification and aiding in voice resonance. There are named for the facial bones in which they are located:
Paranasal sinuses are subject to marked variation between individuals and between sides in the same individual. Paranasal sinus agenesis is rare, and usually involves the frontal sinuses 1.