What are the sinuses?

Sinuses of the face are cavities or spaces within the bones that help humidify air and secrete mucus to help with air filtration. Additionally, they contribute to the strength of the skull and its ability to resist trauma and allow more resonance in the voice.

The sinuses are often referred to as the paranasal sinuses because of their location and connection to the back of the nose. The sinuses develop as air sacs within the bones of the skull and are named by their location:

• Frontal sinus: located above the eyes within the frontal bone of the skull
  
  
• Maxillary sinus: located beneath the eyes under the cheekbones within the maxilla bone of the face
  
  
• Ethmoid sinus: located in the ethmoid bone separating the eyes from the nose
  
  
• Sphenoid sinus: located in the sphenoid bone at the base of the skull