The sinuses are hollow cavities within the facial bones. Sinuses are not fully developed until after age twelve. When people speak of sinus infections, they are most frequently referring to the maxillary and frontal sinuses.
Review Date: 5/21/2013 Reviewed By: Ashutosh Kacker, MD, BS, Associate Professor of Otolaryngology, Weill Cornell Medical College, and Associate Attending Otolaryngologist, New York-Presbyterian Hospital, New York, NY. Review provided by VeriMed Healthcare Network.