
Endoscopic Sinus Surgery - FESS
Endoscopic sinus surgery, or FESS, treats chronic sinusitis and nasal polyps that persist despite sprays and rinses, by removing polyps and opening the sinus drainage pathways through the nostrils with no cuts on the face. A randomized trial showed clearly better symptoms after surgery than with medicines alone. At Biruni Hospital in Istanbul, our ENT surgeons use image guidance, combine septoplasty when needed and follow patients after they return home.
About This Department
Blocked sinuses, polyps and lost smell can last for years. Endoscopic sinus surgery reopens the sinuses through the nostrils, without cuts on the face.
Endoscopic sinus surgery, also called functional endoscopic sinus surgery or FESS, treats chronic rhinosinusitis and nasal polyps that persist despite nasal sprays and rinses. Through the nostrils, the surgeon uses a thin camera to remove polyps and widen the natural drainage pathways of the sinuses, so that air flows, mucus drains and medicines reach the lining. The evidence is strong. In the MACRO trial of 514 adults in the United Kingdom, those who had sinus surgery scored 20 points better on the SNOT-22 symptom scale at six months than those who continued nasal medicines alone (Philpott and colleagues, Lancet, 2025). The benefit lasts, and an English national audit of 3,128 patients found the improvement unchanged five years after surgery (Hopkins and colleagues, Laryngoscope, 2009). This page explains chronic sinusitis, medical treatment, who needs surgery, CT scans, the operation, navigation, risks, recovery, polyp recurrence and biologic drugs, and how patients from abroad arrange endoscopic sinus surgery at Biruni Hospital in Istanbul.
What FESS is
The aim is function. FESS opens the natural drainage pathways of the sinuses and keeps the healthy lining, instead of stripping it away as older operations did.
| Sinus | Location | Drains into |
|---|---|---|
| Maxillary | Cheeks | Middle meatus |
| Ethmoid | Between the eyes | Middle and upper meatus |
| Frontal | Forehead | Frontal recess |
| Sphenoid | Deep behind the nose | Sphenoethmoidal recess |
Chronic rhinosinusitis
| Symptom | What patients notice | Note |
|---|---|---|
| Nasal blockage | Breathing through the mouth, snoring | Main symptom |
| Discharge | Thick mucus, postnasal drip | Front or back of the nose |
| Facial pressure | Fullness over cheeks or forehead | Worse bending forward |
| Loss of smell | Food tastes bland | Typical with polyps |
How is this different from repeated colds?
Polyps in one side only, bleeding or facial numbness need a biopsy to exclude a tumor.
Medical treatment first
| Treatment | How | Duration |
|---|---|---|
| Saline rinses | Large volume squeeze bottle, once or twice daily | Ongoing |
| Steroid nasal spray or drops | Correct technique, head down | At least eight to twelve weeks |
| Short course of oral steroid | For polyps, when safe | One to three weeks |
| Antibiotics | Only for infected flares | Short courses |
Surgery does not replace medical treatment. After FESS, rinses and steroid sprays reach the opened sinuses and work better.
Who needs surgery
Other reasons for sinus surgery
| Situation | Typical procedure | Note |
|---|---|---|
| Chronic sinusitis without polyps | Opening of the affected sinuses | Targeted surgery |
| Nasal polyps | Removal of polyps and opening of all involved sinuses | Wider surgery lowers revision |
| Fungal ball | Removal from the sinus | Cure in most cases |
| Recurrent acute sinusitis | Opening of the drainage pathways | Fewer infections |
Surgery against medicines
| Comparison | Difference in SNOT-22 | Meaning |
|---|---|---|
| Surgery against placebo | 20.4 points better | Large, clinically important |
| Surgery against clarithromycin | 18.1 points better | Large, clinically important |
| Clarithromycin against placebo | 3.1 points, no significant difference | No benefit |
What is the SNOT-22?
| Measure | Result | Note |
|---|---|---|
| Symptom improvement | Stable from one to five years | No decline over time |
| Revision surgery by five years | 19.1 percent | 20.6 percent with polyps |
| Extensive versus limited polyp surgery | Fewer revisions after extensive surgery | Adjusted analysis |
Breathing, smell and sleep
Patients notice the difference within weeks.
Breathing through the nose returns, sleep improves as mouth breathing and snoring settle, headaches from facial pressure fade, and many patients with polyps regain some or all of their sense of smell as the airflow reaches the smell area high in the nose, although smell recovery depends on how long it has been lost and on control of the underlying inflammation with continued steroid sprays. Patients with asthma find their chest easier to control once the nose and sinuses calm down.
Small changes add up to a better life.
CT scan and endoscopy
- Nasal endoscopy in the clinic shows polyps, pus and the drainage pathways.
- A CT scan of the sinuses maps the disease and the anatomy before surgery.
- Allergy tests and blood eosinophil counts help classify the inflammation.
| Test | Purpose | Timing |
|---|---|---|
| Sinus CT | Disease extent, anatomy, safety planning | Within three months of surgery |
| Endoscopy | Polyps, discharge | First visit |
| Blood tests | Fitness, eosinophils | Before surgery |
| Smell test | Baseline smell | Before surgery |
Bring CT images on disc or as a download link. A report alone is not enough for planning.
The operation
No external cuts, no stitches on the face, and in most cases no packing that needs removal.
| Step | Timing | Note |
|---|---|---|
| Admission and checks | Morning | Fasting from midnight |
| Surgery | One to three hours | General anesthesia |
| Recovery | Two to four hours | Head raised |
| Discharge | Same evening or next morning | With rinse kit and medicines |
Navigation and balloon techniques
Image guidance
Balloon sinus dilation widens a sinus opening with a small balloon and suits selected patients with limited disease without polyps. It does not treat polyps.
Is balloon dilation better than FESS?
Choosing the technique
The technique follows the CT findings and the type of inflammation, and the surgeon explains the plan on your own scan before surgery.
Risks
| Complication | Rate | Note |
|---|---|---|
| All major complications | 1.00 percent | Nationwide database |
| Bleeding needing transfusion | 0.76 percent | Most common major event |
| Cerebrospinal fluid leak | 0.17 percent | Repaired endoscopically |
| Orbital injury | 0.07 percent | Very rare |
Signs that need same-day review
We explain each risk in writing before consent, including the risk of polyps returning.
Recovery
| Activity | When | Note |
|---|---|---|
| Desk work | After one week | Physical work after two weeks |
| Blowing the nose | Gently after one week | Sneeze with mouth open |
| Exercise | After two weeks | Swimming after three weeks |
| Flying | After seven to ten days | After the first clinic check |
Follow-up visits
Polyps, recurrence and biologics
Biologic drugs
| Feature | Why it matters | Note |
|---|---|---|
| Polyps on both sides after surgery | Recurrent disease | Main criterion |
| Asthma or aspirin sensitivity | Type 2 inflammation | Higher recurrence |
| Repeated oral steroid courses | Side effects | Steroid sparing |
Living with chronic sinusitis
Chronic sinusitis needs long-term care.
Patients do well with a daily routine of rinses and steroid spray after surgery, a yearly check with endoscopy, prompt treatment of flares and good control of allergy and asthma, while avoiding smoking and irritants that inflame the lining, and those who keep up this routine report the most lasting benefit, with symptoms in the same range years later as in the first months after surgery. Revision surgery, when needed, is planned with the same care as the first operation.
The routine takes minutes a day.
For patients from abroad
Support in Istanbul
Patients combining FESS with septoplasty or rhinoplasty should allow two weeks, because swelling takes longer to settle.
Cost
Compare quotes for the same procedure, and check that follow-up cleaning and navigation are included.
| Factor | Effect | Example |
|---|---|---|
| Extent of surgery | More sinuses, longer operation | Full clearance for polyps |
| Combined procedures | Septoplasty, turbinates | Deviated septum |
| Revision surgery | Navigation, longer operation | Previous FESS |
Biologic drugs
Biologic injections, when needed after surgery, are priced separately and continue in your home country under local supervision.
References
- Philpott C, Beard DJ, Saeedi E, et al. The clinical effectiveness of clarithromycin versus endoscopic sinus surgery for adults with chronic rhinosinusitis with and without nasal polyps (MACRO), a pragmatic, multicentre, three-arm, randomised, placebo-controlled phase 4 trial. Lancet. 2025;406(10506):926-939.
- Hopkins C, Slack R, Lund V, Brown P, Copley L, Browne J. Long-term outcomes from the English national comparative audit of surgery for nasal polyposis and chronic rhinosinusitis. Laryngoscope. 2009;119(12):2459-2465.
- Ramakrishnan VR, Kingdom TT, Nayak JV, Hwang PH, Orlandi RR. Nationwide incidence of major complications in endoscopic sinus surgery. Int Forum Allergy Rhinol. 2012;2(1):34-39.
- Bachert C, Han JK, Desrosiers M, et al. Efficacy and safety of dupilumab in patients with severe chronic rhinosinusitis with nasal polyps (LIBERTY NP SINUS-24 and LIBERTY NP SINUS-52), results from two multicentre, randomised, double-blind, placebo-controlled, parallel-group phase 3 trials. Lancet. 2019;394(10209):1638-1650.
Editor's note
Written by the Biruni Hospital medical editorial team. Reviewed by Specialist Dr. Tural TALIBOV, Neurology.
Medically reviewed by

Specialist Dr. Tural TALIBOV
Neurology
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