We have four pairs of air-filled hollow cavities that function to humidify and filter the air we breathe. There are certain openings that link these cavities to the nasal passages. These openings are called ostium and they function to facilitate the free exchange of mucus and air between the sinus cavities and the nasal airways.
When your mucous membrane produces excess mucus, the ostium stretches and become irritated because of excess mucus that enter and exit the sinus cavities. Most sinus infections follow a typical cold, because with colds excess mucus is produced and if it gets infected, you can land up with sinusitis.
When the ostium become irritated they swell and narrow that air cannot freely flow and mucus is trapped within the sinus cavity. As mucus locates in the sinus cavities, air is prevented from entering causing bacteria and viruses to invade the mucus, which causes inflammation.
There are hair-like structures (cilia) emanating from your mucous membrane that function to sweep mucus down from the sinus region for drainage. When irritated by bacteria, the cilia become impaired and allow mucus to stagnate in the sinus cavity, causing sinus congestion and irritating the soft tissue lining of the sinus wall. |
