Functional endoscopic sinus surgery (FESS)
Anatomy of sinuses
Sinuses are air filled spaces in your facial bones, that lie on the side of your nasal passage. Each sinus cavity is lined by mucus membrane, that produce mucus, which constantly moves through the natural ostium (door) into the nose. The mucus is a way of cleaning your sinuses, because it traps germs, which are moved out of the sterile sinus, into your nasal passage, down the back of your throat and into your stomach.
There are 4 types of sinuses:
- Frontal which lies in your forehead above your eyebrows.
- Maxillary which lies in your cheekbones, below your eyes.
- Ethmoids on the medial or nasal side of your orbits (eye sockets).
- Sphenoid’s at the back of your nose.
Why do you have sinuses?
Sinus cavities lightens your skull, helps with resonance during speech and insulates your eyes from cold air.
Your nose humidifies (with structures called turbinates) and cleans the air that you breathe.
Your nose is divided into two halves by a wall called the septum.
How does sinusitis develop?
When the normal mucus drainage from your sinuses are interrupted, infection develops in the retained secretions. Allergies and viral infections cause swelling of the nasal and sinus mucus membranes, blocking the sinus outflow. Sometimes anatomical problems like septal deviation, excessive air cells (developmental abnormalities), polyps or tumors, cause narrow or blocked sinus openings and recurrent or chronic sinus infection. Immune deficiency, thick mucus production (cystic fibrosis) or ciliary abnormalities can add to mucus build up and sinus infection.
Polyps are benign mucosal growths in the nasal passage and sinuses. They develop due to chronic mucosal inflammation from allergies, immune disorders or chronic infections.
Treatment of sinusitis
Since sinus drainage obstruction is the main cause of infection, treatment is aimed at improving the drainage. Some of the conditions are treated medically. Allergies needs to be treated on a permanent base, if it plays a role in infections or polyp formation. Surgery is considered when mechanical obstruction is the cause or medical treatment fails. Sometimes surgery has to be followed with long term medical treatment, like cortisone nasal sprays.
Functional endoscopic sinus surgery (FESS) is a minimally invasive surgical procedure using endoscopes. Anatomical drainage pathways are enlarged to improve normal draining of sinuses. The frontal sinuses sometimes need to be drilled open in chronic infection and infection of the bone. This is called a Lothrop procedure and is also done endoscopically.
Besides endoscopic surgery to improve drainage of sinuses, I use this type of surgery is for nasal and anterior skull base tumors. CSF or brain fluid leaks are managed on a regular base, with minimal morbidity. For patients with Graves disease and ophthalmopathy (bulging eyes) endoscopic surgery on the eye socket can decompress the eye. Decompression or exploration of the optic (visual) nerve can be done. Blocked tear ducts (lacrimal ducts) can be treated with endoscopic surgery (DCR- dacryocystorhinostomy). As the field and instruments evolve, more and more diseases are being treated with endoscopic sinus surgery.
Like adults, children may also struggle with sinusitis. Sometimes mechanical obstruction is the cause and surgical intervention is needed. Younger children only have ethmoid and maxillary sinuses. The frontal and sphenoid sinuses develop much later (after the age of 7 years). Since everything in children is much smaller, surgery is often more challenging. Some babies are born with the back of the nose blocked (a developmental abnormality called choanal atresia) which is also easily managed with endoscopic surgery. Nasal tumors, like juvenile angiofibroma’s, found in boys (usually from teens) are also managed with this type of surgery. They present with a blocked nose and nose bleeding. Surgery is the main treatment option for the angiofibroma’s.