Functional Endoscopic Sinus Surgery

Functional Endoscopic Sinus Surgery - Scope & Hope

Minimally invasive surgery restoring sinus ventilation & mucociliary drainage.

• Scope: Targets pathology in nasal cavity & paranasal sinuses.
• Core Principle:

  ⭐ Messerklinger's concept of mucociliary clearance pathways being central to sinus health and FESS goals. FESS restores these by clearing osteomeatal complex (OMC) obstruction.

• Goals:
  • Enlarge natural sinus ostia.
  • Remove obstructing pathology.
  • Preserve healthy mucosa.
• Indications:
  • Chronic Rhinosinusitis (CRS) failing maximal medical therapy.
  • Nasal Polyposis.
  • Recurrent Acute Rhinosinusitis (RARS).
  • Fungal Sinusitis.
• Hope: Symptom relief, improved quality of life, ↓medication use.

Functional Endoscopic Sinus Surgery - Scan & Plan

• Computed Tomography (CT) - PNS:
  • Axial, Coronal, Sagittal views: Roadmap for surgery.
  • Assesses disease extent, anatomical variations (e.g., Onodi cell, Haller cells, Keros types of cribriform plate).
  • Lund-Mackay score: Standardized Chronic Rhinosinusitis (CRS) severity grading.
• Diagnostic Nasal Endoscopy (DNE):
  • Visualizes pathology (polyps, pus, discharge), confirms CT findings.
  • Assesses nasal airway, septum, turbinates.
• Pre-operative Checklist:
  • Informed consent (detailing risks: CSF leak, orbital injury, bleeding, infection).
  • Medical fitness evaluation, anesthesia plan.
  • Consider pre-operative systemic steroids or nasal decongestants.

⭐ The Lund-Mackay system is a key CT scoring system for Chronic Rhinosinusitis severity, aiding in surgical planning and prognosis assessment (Max score 24).

Functional Endoscopic Sinus Surgery - Uncinate & Beyond

⭐ The Ostiomeatal Complex (OMC) is the critical drainage area targeted in most FESS procedures for maxillary, anterior ethmoid, and frontal sinuses. Key components: uncinate, infundibulum, hiatus semilunaris, bulla.

• Goal: Restore physiological sinus ventilation & mucociliary clearance pathways.

• Key Principle: Mucosal preservation, targeted removal of pathology, enlargement of natural sinus ostia.

• Core Surgical Sequence (Uncinate & Beyond):

  • Uncinectomy: Pivotal first step; removal of uncinate process.
    • Exposes: Ethmoid infundibulum, natural ostium of maxillary sinus.
  • Middle Meatal Antrostomy (MMA): Widening maxillary ostium.
  • Anterior Ethmoidectomy: Clearing anterior ethmoid cells.
    • Key landmarks: Ethmoid bulla. Basal lamella (divides anterior/posterior ethmoids).
  • Posterior Ethmoidectomy / Sphenoidotomy: For posterior disease extension; sphenoid access via posterior ethmoids.

• Essential Instruments:

  • Endoscopes: 0°, 30°, 45°, 70° for visualization.
  • Microdebrider: For soft tissue and polyp removal.
  • Through-cutting forceps (e.g., Blakesley, Weil).
  • Ball-tipped probe: For exploration & identifying ostia.

Functional Endoscopic Sinus Surgery - Heal & Heed

• Post-operative Care:
  • Saline nasal douching: essential for hygiene, crust removal.
  • Regular debridement: prevents synechiae, aids healing.
  • Avoid nose blowing for 1-2 weeks.
• Healing Timeline:
  • Initial crusting & edema are common.
  • Full mucosal recovery typically takes 6-12 weeks.
• Key Complications:
  • Minor: bleeding, adhesions (synechiae), local infection.
  • Major: CSF leak, orbital injury (e.g., hematoma, EOM damage).

⭐ CSF leak and orbital injury are the most feared major complications of FESS, underscoring the need for meticulous technique.

• Follow-up: Regular visits to monitor healing and manage issues early.

High‑Yield Points - ⚡ Biggest Takeaways

• FESS restores sinus ventilation and mucociliary function.
• Indicated for CRS refractory to medical treatment, and nasal polyposis.
• Uncinate process is the key landmark; its removal opens the ostiomeatal complex (OMC).
• Messerklinger technique emphasizes mucosal preservation around the OMC.
• Coronal CT scan is essential for pre-op assessment.
• Risks: CSF leak, orbital injury (lamina papyracea), major bleeding.
• Endoscopes (0°, 30°) and microdebrider are vital tools.