Sinus Infection (Sinusitis)

Sinus Infection Signs & Symptoms

Sinus infection is characterized by an infection of the lining tissues of the sinuses within the skull. Symptoms of a sinus infection can include

  • pain or pressure sensations over the involved areas of the face along with tenderness and swelling,
  • stuffy nose, or nasal congestion,
  • drainage or discharge from the nose,
  • cough,
  • earache,
  • pain in the jaw or teeth,
  • and nausea.

What is a sinus?

A sinus is a hollow, air-filled cavity. For the purposes of this article, a sinus will referred to those hollow cavities that are in the skull and connected to the nasal airway by a narrow hole in the bone (ostium). Normally all are open to the nasal airway through an ostium. Humans have four pair of these cavities each referred to as the:

  1. frontal sinus (in forehead),
  2. maxillary sinus (behind cheeks),
  3. ethmoid sinuses (between the eyes), and
  4. sphenoid sinus (deep behind the ethmoids).

The four pair of sinuses are often described as a unit and termed the "paranasal sinuses." The cells of the inner lining of each sinus are mucus-secreting cells, epithelial cells and some cells that are part of the immune system (macrophages, lymphocytes, and eosinophils).

Functions of the sinuses include humidifying and warming inspired air, insulation of surrounding structures (eyes, nerves), increasing voice resonance, and as buffers against facial trauma. The sinuses decrease the weight of the skull. If the inflammation hinders the clearance of mucous or blocks the natural ostium, the inflammation may progress into a bacterial infection. Continue Reading

Reviewed on 10/28/2015
Sinusitis Pictures Slideshow: Symptoms, Diagnosis, Treatment


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