Air-filled spaces within the head that lighten the weight of the skull….

Sinuses located behind the ethmoid bone in the skull.

Sinuses located behind the forehead.

Sinuses located under the eyes and within the maxillary (cheek) bones….

The sinuses located at the centre of the base of the skull….

A cut along the edge of the nose to gain access to the nasal cavity and sinuses.

Surgical access to the nasal cavity or sinuses using a cut under the upper lip….