Cortical mastoidectomy ent

Definition: Complete exenteration of all accessible mastoid air cells converting them into a single cavity.

• Posterior Meatal Wall: Left Intact.
• Middle Ear Structures: Not disturbed.

Indications

• Acute Coalescent Mastoiditis.
• Incompletely resolved acute otitis media with Reservoir Sign.
• Masked Mastoiditis.
• Initial Step for:
  • Endolymphatic sac surgery.
  • Decompression of facial nerve.
  • Translabyrinthine/Retrolabyrinthine procedures (Acoustic Neuroma).

Pre-Operative Setup

• Anaesthesia: General Anaesthesia.
• Position: Supine, face turned to one side, ear to be operated uppermost.

Steps of Operation

1. Incision

Standard: Curved postaural incision, 1 cm behind and parallel to retroauricular sulcus.

2. Exposure (Macewen’s Triangle)

• Periosteum incised and scraped from mastoid surface.
• Self-retaining mastoid retractor applied.
• Target: Suprameatal triangle (Macewen’s triangle).

3. Removal of Cortex & Antrum

• Cortex removed with burr or gouge.
• Antrum Depth: 12–15 mm from surface (in adults).
• Landmarks: Identify horizontal semicircular canal.
• Note: Korner’s Septum may need removal to explore antrum.

4. Removal of Air Cells

All accessible cells removed. Boundaries of the cavity:

5. Tip Removal & Finishing

• Lateral wall of mastoid tip removed (exposes posterior belly of digastric).
• Zygomatic Cells: Removed from root of zygoma.
• Retrosinus Cells: Removed from behind sinus plate.
• Finish: Bevelled edges (allows soft tissue to obliterate cavity).

6. Closure

• Irrigate with saline (remove bone dust).
• Drain: Rubber drain at lower end (24–48 h).
• Pack: Meatal pack kept (avoid stenosis).
• Closure in two layers.

Postoperative Care

1. Antibiotics: Continue pre-op meds for 1 week (adjust per culture).
2. Drain: Remove in 24–48 hours.
3. Stitches: Remove on 6th day.

Complications