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Blocked sinuses and sinus infection
90% of adults will suffer blocked sinus and sinus infection at some point, with many suffering from frequently recurring episodes of this uncomfortable illness.
Facial sinuses or paranasal sinuses become blocked very easily when the tissues around them become inflamed during a cold or flu, through allergic reaction, or due to airborne irritation such as second hand smoke.
Some people may be predisposed to sinusitis through structural abnormality in the passages, cysts or polyps - and each bout of sinusitis can increase the chances of recurrence due to a narrowing of the airways.
What are the causes of sinus infection?
A variety of factors can lead to a sinus infection, with the most common being:
Other causal factors include:
The Paranasal Sinuses
1. Frontal sinuses... 2. Ethmoid sinuses
3. Sphenoid sinuses... 4. Maxillary sinuses
The blocked sinus - a quick guide to the how and where
The paranasal sinuses are the maxillary sinuses, frontal sinuses, ethmoid sinuses and sphenoid sinuses.
The sinus that frequently causes most problems is the maxillary - the largest of the sinuses, being situated below the eyes on the cheeks. The design of the maxillary sinus is flawed, with the passage where mucus drains from being near its roof, meaning mucus is not free draining at the best of times. Given local inflammation it will block rapidly.
Due to the maxillary sinus being close to the frontal and ethmoid sinuses and the roots of teeth, once blocked, infections can spread quickly to neighbouring sinuses and tissue. Infected and blocked maxillary sinus symptoms include localised pain or pressure in the cheek, toothache and headache.
The frontal sinus is absent in babies, only becoming well developed by eight and fully developed at puberty - and 5% of adults have none. Inflammation and infection of the frontal sinuses may cause serious complications because they are so close to the brain - complications including meningitis, subdural abscess and cellulitis. Symptoms of a blocked frontal sinus include pain or pressure above the eyes and headache.
The ethmoid sinuses lie between the eyes forming part of a complex structure within and behind the nose. Once blocked they cause pain and pressure between and behind the eyes, as well as localised headache.
The sphenoid sinuses only develop fully at puberty and are found at the far rear of the nasal cavity. Much like the frontal sinus complications of sphenoid sinusitis are potentially dangerous due to their proximity to the brain. Complications include cavernous sinus thrombosis - a blood clot within the brain. Symptoms of sphenoid sinusitis are pain or pressure behind the eyes that is also felt at the top of the head.
Sinus headaches are often confused with migraine headaches. This is because the nerves receive the same type of pain signals from both causes and recent studies have shown that 90% of what are first thought to be sinus headaches, actually respond to migraine medication but show no relief from decongestant or antibiotics.