The Facts
The sinuses are hollow spaces in the bones behind the face. Directly
behind the nose is a cavity. On either side of the nasal cavity are large sinuses.
A row of very small sinuses runs behind the bridge of the nose, and two more
large sinuses are located above and behind the inner part of the eyebrows. Sinusitis
is inflammation of the sinuses. It may be associated with both bacterial and
viral infections, but it may be due to non-infectious inflammation in the sinuses
as well. It's extremely common, affecting about one person in 10 each year,
both children and adults.