The paranasal sinuses communicate with the nasal cavities through small orifices called ostia; this is why an inflammation of the nose may spread to the sinuses, causing rhinosinusitis.
Inflammation leads to congestion of the mucous membranes of the sinuses and blockage of the ostia, and prevents the mucus from being pushed toward the nose. Such “stagnation” can facilitate bacterial infections.
Congestion of the mucous membranes of the sinuses can cause a sense of heaviness in correspondence to the jaw, the forehead and the areas above and below the eyes. If the cause is a viral or a bacterial infection, rhinosinusitis may be accompanied by fever.
In the most serious cases, the pain may be severe and can worsen in the supine position or if the head is inclined forward. Serious rhinosinusitis can also lessen our capacity to perceive tastes and odors.