Sinusitis, also called rhinosinusitis, is the inflammation
of the lining of the sinuses (the nasal passage).
Depending of the sinus cavity affected, sinusitis is classified as:
- Maxillary, affecting the cheek and sometimes the teeth;
- Frontal, causing headache in the forehead;
- Sphenoidal, that may cause discomfort in the back of the head; and
- Ethmoidal, which can also cause headache above the eyes.
Most causes are due to microorganisms (mainly viral but also bacterial or
fungus) or autoimmune disorders. However, anatomical abnormalities may represent
an important factor to develop the condition.
Headaches in the forehead and blocked or runny nose are the main symptoms of
sinusitis. Bacterial sinusitis usually produces fever, facial pain and swelling
and last longer than viral sinusitis.
Image of the head of a patient with right maxillary and frontal sinusitis.
Sinusitis is chronologically classified as follow:
- Acute sinusitis. It may last up to 4 weeks and can be recurrent;
- Subacute sinusitis lasts 1 to 3 months; and
- Chronic sinusitis, which refers to an episode that last for more than 3 months.
Sinusitis is not a contagious condition and may appear as result of a recent
episode of flu or cold.