Functional endoscopic sinus surgery (FESS) is minimally invasive surgery for serious sinus conditions. Healthcare providers use nasal endoscopes — thin tubes with lights and lens — to ease your sinus symptoms without making incisions in or around your nose. Studies show between 80 % and 90% of people who’ve had this surgery feel it solved their sinus issues.

Functional endoscopic sinus surgery is also called endoscopic sinus surgery. Some healthcare providers use the term “functional” because the surgery is done to restore the normal ‘function’ of your sinuses.

It is routinely performed for chronic sinusitis, nasal polyposis, allergic fungal sinusitis, for closure of CSF Rhinorrhoea (ESS) etc.