Understand why your nose & sinus is blocked

Dr Kevin Soh reveals the different causes for block nose. He illustrates with interesting graphics and videos. Understand deviated nasal septum, nasal polyps, enlarged adenoids.

How to get rid of fungus in your sinus

Dr Kevin Soh describes what is fungal sinusitis, and how it can cause nose polyps. Learn how surgeons approach the maxillary sinus.

Your skull is filled with air!

The sinuses are air filled spaces in the skull. Most people do not realize these spaces exist in the skull until a problem develops, and they begin to experience the symptoms of sinusitis.

There are 4 pairs of sinuses,

  • Maxillary sinus – behind the cheeks
  • Ethmoid sinus – between the eyes behind the bridge of the nose
    The other two develop later:
  • Frontal sinus – Developed around the age of seven, these are located in the area of the forehead, over the brow.
  • Sphenoid sinus – Developed during adolescence, a last pair deep in the center of the head (sphenoid).

The sinuses are conneckted to the nose and nasal cavity by way of small openings called ostia. Except for the ethmoid sinuses between the eyes, the other sinuses are poorly developed at birth. They normally commence development in later childhood to attain their adult size at the onset of puberty.

Interestingly, no one fully understands the purpose for the existence of the sinuses. One explanation is that the sinuses, being air-filled spaces, cause the skull to weight less than if it had consisted entirely of solid bone. Another reason may be that the sinuses act as a protective buffer zone in injuries of the face, preventing force from being transmitted directly to the vital structures in the skull. Whatever their benefit, one thing is for sure – the sinuses can be the cause for a lot of trouble.

The sinuses all lead to the nasal passages. They are linked by a mucous membrane. When the mucus is thin (under healthy circumstances), it is swept out by miniscule hairs along the sinuses called “cilia”, and draws bacteria and fungus out of the body through the nose.

You can get sinusitis only if you have sinuses

Individuals who do not have a particular sinus will not develop sinusitis in that area. For example, 10% of people in the general population will have underdeveloped frontal sinuses. This makes it impossible for them to suffer from the excruciating headaches of frontal sinusitis.

A patient of mine, Mr. Tan, first realized how troublesome sinusitis can be when he first contracted the infection 2 years ago. The symptoms first started as a flu, which caused blocked nose, runny nose, and pain over the cheeks. The pain got worse, and reached a crescendo 3 days later, when it was so painful that he was unable to go to sleep. He would wake up in the mornings feeling that he had not slept at all. The pain in the cheeks had also extended to involve the forehead, and the top of his head. By this time, his nose was so blocked that he had to open his mouth to breathe. He would wake up the next day with a very dry and sore throat.

Furthermore, he could not enjoy his meals as his sense of smell and taste had gone. Initially he thought that the symptoms would go away in a week. However, when the symptoms continued to persist, and his ability to work was affected, Mr. Tan became desperate.

Over the next few months, he consulted many doctors and was given a myriad of different medications. He even sought treatment from several Chinese traditional physicians without benefit. Finally, one of the doctors he consulted had the wisdom to perform an endoscopic examination of his nose, and discovered that his sinus openings are blocked by swelling.

He went through a computed tomographic scan (CT scan) which demonstrated that he had sinusitis of both his maxillary and frontal sinuses. Sinus surgery was performed under general anaesthesia. One week later, his symptoms of pain, sorethroat, and inability to smell had disappeared. Since then, he has been enjoying very restful and peaceful nights of sleep.

Fortunately, many people suffer from sinusitis, but few need surgery for resolution of their symptoms. Most sinusitis can be treated with medications like antibiotics, decongestants, and antihistamines. Others may need simple outpatient procedures like a washout of their sinuses to flush away the pus and to open up the sinus ostia.

What is a Sinus Infection?

A sinus infection occurs when a pathogenic organism (virus, bacterium, or a fungus) grows within a sinus and causes intermittent blockage of the sinus ostium. Drainage of mucus and pus often occur when the blockage is relieved. The drainage usually goes from the nasal passages to the throat or out of the nostrils. Such infections also cause inflammation (an influx of immune cells and swelling of the sinus tissue) of one or more sinuses. This adds to blocking the openings of the sinuses and causes discomfort.

Inflammation of the air cavities within the passages of the nose (paranasal sinuses) is referred to as sinusitis. Sinusitis can be caused by infection, but can also be caused by allergy and irritation of the sinuses.

Allergy is the main cause of sinusitis

The most common cause of sinusitis is allergic rhinitis, which accounts for up to 80% of cases of sinusitis.

The allergic response occurs as a result of an over-exaggerated response by the body’s immune system to harmless benign substances that enter the body from the outside environment.

The reaction causes the lining of the nose to become inflamed and swell up (rhinitis), resulting in obstruction of the sinus ostia, and poor drainage of the sinuses.

Secretions build up, providing a good growth medium for bacteria, allowing them to flourish in an unimpeded fashion within the sinuses. Pus forms and accumulates under pressure, allowing some of it to squeeze and escape through the narrowed ostium into the nasal cavity. This gives rise to the yellow nasal discharge that is seen in sinusitis.

Sinusitis can have a variety of other causes. The common final pathway by which all these other diseases cause sinusitis is through obstruction of the sinus ostia resulting in poor sinus drainage. Thus, deviation of the nasal septum, foreign bodies, cancer, and nasal polyps can cause obstruction to the sinus ostia, giving rise to sinusitis. As allergic rhinitis is the most common cause of sinusitis, it is imperative that an allergic process is assumed, and the offending allergen searched for in all cases of sinusitis. The allergen, or the substance that causes allergy, can come into our bodies through the air that we breathe in or from the foods that we consume.

Both inhalant and food allergies can be tested very simply through a blood or skin test. If the offending inhalant or food allergen is identified, and the appropriate treatment measures taken, a dramatic improvement in sinusitis usually occurs. This obviates the need for medications, antibiotics and surgery.

Symptoms of Sinusitis

Symptoms of Sinusitis vary from person to person.  While one person may have all the symptoms, someone else may have only one or two of them.  The most common symptoms are:

  • Stuffy or runny nose/blocked nose
  • Discharge from the nose or thick yellow or green discharge from the nose, sometimes, tinged with blood
    • Cheek pain or dental pain assocated with Maxillary sinusitis.
    • Forehead pain indicates frontal sinusitis.
    • Pain at the bridge of the nose or behind the eye suggests ethmoid sinusitis. Pain is often referred to the top of the head with sphenoidal involvement.
    • Headache
    • Eye pain due to a spread of infection from the sinuses to the eye
    • Postnasal drip from the nose into the throat
    • Reduced sense of smell or/and taste
    • Bad breath
    • Earache, feeling of fullness in the ear, swelling and tenderness behind the ear, and/or ear popping due to mucus in the eustachian tube of the ear.

Sinusitis is subdivided into:

  • Acute sinusitis – symptoms lasting < 4 weeks
  • Subacute sinusitis – symptoms lasting between 4 weeks to 3 months
  • Chronic – symptoms lasting more than 3 months

Treatment of Sinusitis

  • Acute Sinusitis – Management is usually medication.  Medication includes broad spectrum antibiotic, nasal decongestants, anti-histamines and prescription inhalers.  Occasionally, sinus washout may also be prescribed.  A word of caution: Over the counter decongestants shrink the nasal blood vessels and decrease oxygen supply to nasal cells, resulting in burning sensation and permanent damage when used excessively.  Sufferers have to be aware that if inadequately treated, acute sinusitis can result in irreversible changes to the sinus lining that can lead to chronic sinusitis.
  • Chronic Sinusitis – medical therapy is often considered an adjunct to surgical treatment and is directed toward controlling the predisposing factors, treating the infection, restores drainage of the sinuses.
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