paranasal sinus

Pronunciation: (PAYR-uh-NAY-zul SY-nus)

One of many small hollow spaces in the bones around the nose. Paranasal sinuses are named after the bones that contain them: frontal (the lower forehead), maxillary (cheekbones), ethmoid (beside the upper nose), and sphenoid (behind the nose). The paranasal sinuses open into the nasal cavity (space inside the nose) and are lined with cells that make mucus to keep the nose from drying out during breathing.

Source: NCI Dictionary of Cancer Terms

Anatomy of the paranasal sinuses (spaces between the bones around the nose).Anatomía de los senos paranasales (espacios dentro de los huesos que rodean la nariz).2007-03-16 Date last modified: 2012-04-30Paranasal Sinus and Nasal Cavity Cancer TreatmentCáncer de seno paranasal y de cavidad nasal: Tratamiento