The sinuses are air-filled pockets in your head. We have four sinuses on each side, the maxillary sinus, the frontal sinus, the ethmoid sinus, and the sphenoid sinus. The sinuses and nose warm the air we breathe, humidify the air, and trap pollutants, dust, and bacteria.

What are the sinuses?

Paranasal sinuses are air-filled pockets located in the head. There are four pairs of sinuses.

The sinuses have a self-cleaning mechanism, called mucociliary clearance.

A diagram shows what triggers sinusitis

How do healthy sinuses work?

A graphic that depicts what happens to the sinus before balloon sinuplasty

When you breathe in air, mucus in the sinuses humidifies the air and collects bacteria and pollutants.

Tiny hairs lining the sinus move the mucus (with pollutants) out of the sinus, into your throat. You then swallow the mucus, and your stomach acid destroys the bacteria and pollutants.

A graphic that depicts what happens to the sinus before balloon sinuplasty

Tiny hairs, or cilia, on the lining of the sinuses and nose sweep out material to keep the sinuses and nose continually clear. The material is swept out of the nose, you swallow it, and stomach acid destroys the bad stuff.

A diagram shows what triggers sinusitis

How it can break down

The critical event that makes sinuses bad is blockage of the opening to the sinuses. Once the sinus is clogged, pollutants, dust, and bacteria cannot get out and become trapped. Mucociliary clearance stops. This trapped material festers, ferments, and becomes an infection. A trapped sinus creates pressure (felt as a headache), spews drainage from time to time (runny nose or phlegm), and clogs the nose (nose is stuffy or congested).

What is Sinusitis?

Sinusitis or rhinosinusitis is an inflammation of the tissue lining of the sinuses. It can lead to poor or blocked sinus drainage and infection. Sinusitis affects millions of people each year.
A graphic that depicts what sinusitis is

Normally, sinuses are filled with air.

Sinus pathway becomes swollen.

Blocked sinuses fill with fluid.

Pathogens can grow and cause infection.

Sinusitis is the condition of inflammation of the lining of the sinuses. This is caused by the blockage of the sinus opening and growth of organisms that are trapped inside. Once the sinus opening gets blocked, bacteria tend to grow and create pressure inside the sinus. This turned into a pressure cooker. Symptoms of sinusitis are a headache, facial pressure, nasal congestion or blockage, nasal drainage, post-nasal drip or runny nose, fever, fatigue, bad breath, cough, and pain in the upper teeth. Sinus headaches are very common. Headaches are the reason for many missed days of work and school.

Causes of Sinusitis

The common cold and allergies are the most common causes of sinusitis. Other causes can be pollutants, environmental irritants, tobacco smoke, a deviated septum (blockage of the nose), nasal polyps (also block the nose) or dental infections. Each of these causes leads to blockages of the sinuses at their openings.

Diagnosing Sinus Problems

The History
The information told to us by the patient is the best way to diagnose sinusitis. Tell your doctor about headaches, facial pressure, runny nose, post-nasal drip (mucous in the back of your throat), nasal congestions, upper teeth pain, etc.

Nasal Endoscopy

A fiberoptic scope is passed into the nose to examine inflammation, pus and blockage. Also known as rhinoscopy or endoscopy.


A CT scan can show the details of the anatomy, inflammation, infection, and points of blockage.
A machine that does CT imaging
Doctor Vincent looking at a CT scan


A sample of mucus from the nose can be sent to the lab to identify the bacteria or fungus causing the sinus infection. This helps in finding the right antibiotics, specific for the bacteria present. It also proves that the infection is present.

Allergy Testing

Testing can identify the triggering event that causes sinus to come back again and again. Allergy tests can be as simple as a blood test or can be a skin test.

There are also numerous over-the-counter medications in pharmacies or grocery stores for sinus conditions. Hot or cold packs may help.

Many things can help with secretions, to clear mucus up and get rid of it. Steaming, either through a store-bought facial steamer or home-made version may help. Nasal rinsing with saline, a mist or a jetted spray, a Neti pot, a nasal cleaner or irrigator such as Navage may help.

Treatment for sinus headaches is aimed at trying to get the sinus to open up. Decongestants or nasal steroid sprays help in opening up a blocked sinus. If the condition is prolonged, an antibiotic might be necessary to help to eliminate the bacteria inside the sinus.

Keeping your air filter clean in y our house or replacing reduces exposure to dust and pollutants. You may also buy a portable air filter unit.

Room humidifier

Treating Sinusitis

There are three main ways to address sinus problems.


Medicine icon

Medications help with symptoms but do not treat the underlying cause. This is the first approach taken and, for most people, will allow them to live their normal lives.

Balloon Sinuplasty

Patient chair and a window

If medications don’t adequately control the sinus problems, it may be necessary to treat the underlying cause by improving the sinus outflow. Learn more about Balloon Sinuplasty.

Traditional Sinus Surgery

Operation room icon

If neither medication nor balloon sinuplasty addresses the sinus problems, it may be necessary to perform surgery to correct the sinus structural issues.