The sinuses are a connected system of hollow cavities in the skull. The largest sinus cavities are around an inch across; others are much smaller. The sinuses are lined with soft, pink tissue called mucosa. Normally, the sinuses are empty except for a thin layer of mucus. The inside of the nose has ridges called turbinates. Normally these structures help humidify and filter air. The nose is divided in the center by a thin wall, called the septum. Most of the sinuses drain into the nose through a small channel or drainage pathway called the middle meatus. The purpose of the sinuses is unclear. One theory is that sinuses help humidify the air we breathe in; another is that they enhance our voices.
Related journals of Sinuses
Nasopharyngeal carcinoma, Journal of NasoPharyngeal Carcinoma, British Journal of Cancer