Sinus Surgery — Procedure Guide, Recovery & Risks | MyMedicPlus

Functional endoscopic sinus surgery (FESS) is a minimally invasive ENT procedure that uses rigid nasal endoscopes — typically 0° and 30° angled scopes — and powered microdebrider instruments to open the natural drainage pathways of the paranasal sinuses (maxillary, ethmoid, frontal, and sphenoid), removing obstructing disease (polyps, thickened mucosa, bony partitions) while preserving the mucosa and mucociliary clearance mechanism as much as possible.

The procedure is guided by pre-operative CT scanning of the paranasal sinuses, which provides a detailed road map of individual anatomy, sinus dimensions, and pathology extent. Image guidance (intraoperative CT navigation) is increasingly used for complex, revision, or anatomically challenging cases to provide real-time three-dimensional localisation of surgical instruments, significantly reducing the risk of inadvertent orbital or intracranial entry.

FESS represents a paradigm shift from earlier radical procedures (Caldwell-Luc operation) that removed all sinus mucosa and created inferior antrostomies — now largely abandoned in favour of the functional approach that enlarges natural sinus ostia and restores physiological drainage. The vast majority of sinus surgery today is performed endoscopically as a day-case procedure. FESS may address the maxillary, anterior and posterior ethmoid, sphenoid, and frontal sinuses individually or in combination, depending on the extent of disease on CT.

FESS is indicated for patients with chronic rhinosinusitis (CRS) — inflammation of the nasal cavity and paranasal sinuses lasting more than 12 weeks — with or without nasal polyps, that has not responded to appropriate medical therapy. Medical management includes high-volume nasal saline irrigation, topical intranasal corticosteroids for a minimum of 3 months, oral corticosteroid courses for polyps (prednisolone 30–40 mg for 7–10 days), and targeted antibiotic therapy for acute-on-chronic infections guided by culture results.

Specific indications include: CRS with nasal polyposis causing significant olfactory loss, nasal obstruction, and poor quality of life; CRS with complicating acute sinusitis not responding to antibiotics; orbital complications of sinusitis (subperiosteal abscess, orbital cellulitis); intracranial complications (epidural or subdural abscess, meningitis); antrochoanal polyp (originating from maxillary sinus, extending into the nasopharynx); and fungal sinusitis requiring drainage.

FESS is also used for the removal of inverted papilloma (benign but locally aggressive sinonasal tumour), sinonasal malignancy debulking, dacryocystorhinostomy (DCR, opening blocked tear ducts), pituitary tumour approach (endoscopic transsphenoidal surgery), and repair of CSF (cerebrospinal fluid) leaks.

FESS is performed under general anaesthesia as day surgery. Topical vasoconstrictor (oxymetazoline or xylometazoline) is applied to the nasal mucosa; local anaesthetic with adrenaline (lidocaine 1% with 1:80,000 adrenaline) is injected into key anatomical sites to provide additional haemostasis and anaesthesia.

A 4 mm 0° rigid endoscope is introduced into the nasal cavity and the anatomy systematically assessed. Image-guided navigation (if used) is registered using a Brainlab or Stryker electromagnetic system referenced to the pre-operative CT scan.

Uncinectomy (removal of the uncinate process, a bony projection) opens access to the maxillary sinus ostium. The anterior ethmoidal air cells are opened sequentially (anterior ethmoidectomy). Middle meatal antrostomy enlarges the natural maxillary sinus ostium to 8–10 mm, enabling adequate drainage. Posterior ethmoidectomy opens posterior air cells. Sphenoidotomy opens the sphenoid sinus if disease is present. Frontal sinus drainage is addressed via a Draf I (removing anterior ethmoid cells) or Draf IIa/IIb (enlarging the frontal drainage pathway) procedure.

Nasal polyps are removed with a powered microdebrider (cutting and suction combined). Complete removal is not the goal — functional opening of drainage is. Haemostasis is achieved with suction cautery or packing. Absorbable packing (Nasopore, Surgicel) or silicone stents may be placed to prevent adhesion formation and maintain ostia patency. Operative time: 60–120 minutes depending on extent.

FESS is performed as day surgery; patients return home the same day or after one overnight stay. Absorbable packing dissolves over 2–3 weeks; non-absorbable packing (if used) is removed the following morning. Patients experience nasal congestion, bloody discharge, and mild facial pressure for 1–2 weeks, which progressively resolves as the sinuses heal.

Post-operative nasal irrigation with high-volume saline (240 mL Neilmed or similar) is the cornerstone of aftercare, commenced the day after surgery and continued twice daily for 4–6 weeks. Irrigation flushes blood clot, crusts, and inflammatory secretions from the newly opened sinuses, significantly reducing adhesion formation and improving long-term outcomes. Topical corticosteroid nasal spray is restarted at 2–4 weeks post-operatively.

Gentle nasal douching allows the patient to see blood-stained crusts in the irrigation fluid — this is expected and not alarming. Heavy nose-blowing and strenuous exercise are deferred for 2 weeks. Clinic debridement (endoscopic removal of crusts and adhesions) is performed at 1 week and 4 weeks — an important step often overlooked in general practice follow-up. Most patients return to work within 5–7 days; final functional outcome assessed at 3–6 months.

Major complications are rare (less than 1%) but include: orbital injury from breach of the medial orbital wall (lamina papyracea), causing orbital haematoma, diplopia (double vision), or permanent visual loss — requiring immediate ophthalmological assessment; intracranial penetration through the cribriform plate causing CSF leak, meningitis, or intracerebral haematoma; and haemorrhage requiring packing or return to theatre. These serious complications are significantly reduced by CT image guidance and careful adherence to anatomical landmarks.

More common complications include: post-operative epistaxis requiring repacking (1–2%); adhesion formation (synechiae) between the lateral nasal wall and septum reducing surgical benefit (5–10% without appropriate aftercare); and anosmia (loss of smell) from olfactory epithelium injury. Orbital emphysema (air entering the orbit) from nasal blowing is prevented by advising against forceful nose-blowing.

Disease recurrence — most commonly recurrent nasal polyps — is the most frequent long-term issue, occurring in 20–40% within 5 years, particularly in eosinophilic CRS with polyps (CRSwNP). Biological therapy (dupilumab) for Type 2 inflammatory CRS reduces polyp recurrence and may delay or prevent the need for revision surgery.

FESS achieves significant symptom improvement in 80–90% of patients at 12-month follow-up, measured by the SNOT-22 (Sino-Nasal Outcome Test) — a validated 22-item questionnaire. The mean SNOT-22 improvement after FESS exceeds the minimal clinically important difference of 9 points, demonstrating meaningful benefit over the best medical therapy alone in controlled trials.

Nasal blockage, facial pressure, purulent discharge, and reduced smell all show significant improvement. Anosmia (complete loss of smell), present in 80% of patients with severe polyposis, partially recovers in 60–70% of patients following FESS and post-operative topical corticosteroids. Recurrent acute exacerbations of chronic sinusitis are reduced in frequency by 50–70%.

The economic benefit is also significant: FESS reduces GP visits, antibiotic prescriptions, oral corticosteroid courses, and emergency department attendances for sinus infections. Quality-of-life improvements persist at 5-year follow-up in most patients who complete post-operative medical management. The procedure preserves the mucosal lining and mucociliary clearance mechanism, avoiding the long-term complications of radical sinus surgery.