Endoscopic Sinus Surgery | ENT Consultant

What is an endoscope?

The ability to properly view the nasal cavity with this instrument has transformed nasal surgery. Prior to its introduction the nose could only be examined with a headlight which meant that instead of enlarging the natural drainage passageways abnormal openings were fashioned and nasal mucosa was stripped. This resulted in scarring and post-operative crusting.

The instrument is shown below together with the view it provides of pus in the right middle meatus (drainage passageway).

When is endoscopic sinus surgery indicated?

When medical management fails to resolve sinusitis or nasal polyposis, surgery is indicated. This has been revolutionised in recent years by:

An improved understanding of the natural drainage passageways from the sinuses. Previously surgery took no account of this. We aim to restore natural sinus anatomy and functioning.
Better imaging techniques including CT and MRI scans allow for a precise diagnosis of the problem including the extent of the disease and any underlying anatomical factors which predispose to sinusitis
Improved instrumentation allows for focused surgery with less post-operative bleeding and usually no need for nasal packing
Balloon Sinuplasty

What other instruments have transformed sinus surgery and why?

Basic research by Messerklinger confirmed the importance of healthy mucosa to the normal functioning of the nose. This heralded a change in philosophy away from stripping mucosa towards through-cutting and mucosal preservation. This means that post-operatively the nasal cavity is lined by healthy mucous membrane rather than having exposed bone over which scar tissue forms.

Why are CT scans necessary?

Although the CT scan opposite beautifully demonstrates sinus anatomy they are not usually required for diagnostic purposes.They are however necessary to prevent complications. Because sinus anatomy varies significantly between individuals the scans are necessary to delineate the anatomy of the paranasal sinuses and their relationship to adjacent structures such as the anterior skull base, optic nerve and internal carotid artery.

What are the risks of sinus surgery?

All operations carry risk and endoscopic sinus surgery is no different. The risks are identical to those of simple polypectomy but arguably (because of the better view afforded by the endoscope and the anatomical information provided by the CT scan) much less likely to occur.

The problems which have been reported in the literature arise because of damage to adjacent structures. The CT scan below shows the proximity of the nasal sinuses to the orbit and anterior skull base. Further back the sinuses are related to the optic nerve and internal carotid artery. Damage to these structures would clearly lead to serious complications.

For example breach of the skull base would cause a leak of cerebrospinal fluid (which bathes the brain) into the nose. This might result in meningitis. Mr Mckiernan has never personally caused such a complication but has experience of managing them. This all serves to underline the importance of training and subspecialisation.

Is endoscopic sinus surgery conventional surgery with an endoscope?

No. The philosophy of FESS (functional endoscopic sinus surgery) is to preserve healthy nasal mucosa and restore normal anatomy and functioning. Older style operations deal with those parts of the nose which are readily accessible with a headlight. So, for example, in order to drain the cheek sinus a new opening would be fashioned low down in the nose instead of enlarging the natural drainage passageway. Of course the nasal secretions still move towards the natural opening which remains blocked! In FESS the natural drainage passageway would be enlarged.

How successful is endoscopic sinus surgery?

Research has confirmed that endoscopic sinus surgery is successful in treating nasal polyps, facial pain caused by sinus disease and sinus infections although there is a rendency for polyps to recur and maintenance therapy will be required. It may also help with snoring and improve your sense of taste and smell. What we call ‘postnasal drip’ is not well addressed by this or any other surgery. There are however a variety of medical treatments which might help.

The extended role of endoscopic sinus surgery

Increasingly conventional ‘open approaches’ to the nose and adjacent structures are being superseded by minimally invasive endoscopic approaches. These can be used in:

Tear duct and lacrimal sac surgery (‘endoscopic dacrocystorhinostomy’ or ‘DCR’)
Frontal sinus surgery
Repair of CSF leaks
Cosmetic surgery for prominent eyes often associated with thyroid disease (‘orbital decompression’)
Arterial clipping to control nosebleeds (‘sphenopalatine artery ligation’)

I perform all of the above operations in addition to ‘open approaches’ where indicated.