Functional Endoscopic Sinus Surgery (FESS)

One way FESS differs from traditional sinus surgery is that a thin rigid optical telescope, called an endoscope, is used in the nose to view the nasal cavity and sinuses. This technique was developed in Europe and introduced into the US by Dr. David W. Kennedy from the University of Pennsylvania in the mid 1980s. It has revolutionized the surgical treatment of chronic sinusitis.  FESS generally eliminates the need for an external incision. The endoscope allows for better visualization and magnification of diseased or problem areas. This endoscopic exam, along with CT scans, may reveal a problem that was not evident before.

Another difference is that FESS focuses on treating the underlying cause of the problem. The ethmoid sinuses are usually opened. This permits direct visualization of the maxillary, frontal, and sphenoid sinuses and diseased or obstructive tissue can be removed if necessary. There is often less removal of normal tissue and surgery can frequently be performed on an outpatient basis without the need for painful packing that was used in the past. Generally, there are not external scars, little swelling, and only mild discomfort.

The goal of FESS is to open the sinuses more widely. Normally the openings to the sinuses are long narrow bony channels covered with mucosa or the lining of the sinuses. If this lining swells from inflammation, the sinuses can become blocked and an infection can develop. FESS removes some of these thin bony partitions and creates larger openings into the sinuses. After FESS, patients can still develop inflammation from allergies or viruses, but hopefully when the sinus lining swells, the sinus will still remain open. This will permit easier treatment of subsequent exacerbations with more rapid resolution and less severe infections.

Powered instrumentation can be useful during FESS to precisely remove polyps and other diseased tissue, while sparing the surrounding normal sinus lining and adjacent structures. The latest generation of hand instruments allows the surgeon to meticulously open the sinuses, while avoiding the “grab and tear” techniques of the past. Once the diseased tissue is removed and the inflammation subsides, the injured sinus lining often returns to a normal state with time.


 Computer assisted surgical navigation is a relatively new tool used in select cases. These devices provide information on the anatomic location of instruments within the sinuses during surgery and can also be used to perform 3D reconstructions that may be helpful to your surgeon. It is typically indicated for revision cases, nasal polyposis, or skull base tumors where normal surgical landmarks have been removed or altered. As with all equipment, image-guided systems can be wrong from time to time and surgeons cannot rely solely on the technology. They must correlate the image-guided information with their training, experience, and knowledge of the anatomy in order to avoid complications due to human or technical errors.

Functional Endoscopic Endonasal Laser Surgery - FEELS

With excellent optical properties and digital video technology, rigid endoscopes caused a revolution in functional endoscopic paranasal sinuses surgeries and resulted in a reduction of surgical trauma, while simultaneously improving the overview of the operating site.