Sinusitis refers to inflammation of the sinus cavities, which are
moist, hollow chambers in the bones of the skull. There are four
pairs of sinuses:Frontal sinusesMaxillary sinusesEthmoid
sinusesSphenoid sinuses (not shown in illustration)If the opening
from a sinus cavity becomes plugged, the flow of mucus is blocked
and pressure builds up, causing pain and inflammation.
Review Date: 06/02/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine,
Harvard Medical School; Physician, Massachusetts General Hospital.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
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