The sinuses are an interconnected system of hollow cavities in the skull comprised of the: Maxillary sinuses in the cheeks Ethmoid sinuses between the eyes Splenoid sinuses between the eyebrows and upper bridge of the nose Frontal sinuses in the forehead.
During FESS, a small, rigid or flexible tube—called an endoscope—is inserted through one nostril. A tiny camera attached to the tube transits live images to a video monitor, allowing the surgeon to visualize the sinuses. They can then use special surgical instruments inserted through the same nostril to perform various functions.
For example, the surgeon may remove infected sinus tissue, a nasal polyp, or even a foreign body. Tiny bones that line the sinus openings may also be removed to provide better ventilation and drainage of the sinuses.
The benefit of FESS over older, more invasive sinus surgery techniques is that it allows for direct visualization inside the nose. This is important as nasal pathologies (e.g., polyps or other blockages) are often the primary culprit behind a patient's sinus condition.
Endoscopic sinus surgery offers other benefits too. One study found that an endoscopic middle meatal maxillary antrostomy was superior to the more invasive Caldwell-Luc operation (removal of tissues from the maxillary sinuses via a hole in the gums) with regard to patient comfort, bleeding during the operation, days of hospital stay, alleviation of symptoms, and disease resolution.
While traditionally used as a sinus surgery technique, keep in mind that FESS may also be used to treat certain eye conditions. In these cases, the eye socket or optic nerve is accessed through the nose and sinus passageways.