Petrositis

🦻 Petrositis

Petrositis is a complication of chronic otitis media (COM) where infection spreads from the middle ear and mastoid to involve the petrous part of the temporal bone.

What are the different types of pneumatisation of petrous apex?

What are the two different pneumatisation pathways of petrous apex?

🧬 Pathophysiology of Petrositis

• Chronic otitis media → Mastoiditis → infection spreads along pneumatization tracts to petrous apex

• Similar pathological process as acute mastoiditis:

  • Pus under tension
  • Hyperemic bone decalcification

What is the canal through which 6th cranial nerve passes?

Where is Trigeminal ganglion located?

🩺 Clinical Features of Petrositis

Symptoms

• Persistent ear discharge

• Retro-orbital or deep-seated facial pain

• Diplopia on lateral gaze

• Fever, headache, vomiting

• Facial nerve palsy or recurrent vertigo

What is Gradenigo Syndrome? What is the triad seen in Gradenigo symdrome?

Signs

• Ear: Discharge, central Tympanic Membrane perforation

• Tuning fork tests:

  • Rinne – Negative
  • Weber – Lateralized to diseased ear
  • Absolute bone conduction – Normal

• Eye exam: Diplopia on lateral gaze

• CNS exam: Rule out meningitis or other intracranial complications

🔍 Investigations of Petrositis

1. CT Temporal Bone – Shows bone erosion & pneumatization status

2. MRI Brain – Differentiates diploic marrow from fluid/pus

💊 Treatment of Petrositis

Medical

• High-dose IV antibiotics (e.g., cephalosporins)

• Continue for 4–5 days after symptom resolution

Surgical

• Options:

  • Cortical mastoidectomy
  • Modified radical mastoidectomy
  • Radical mastoidectomy

What are the indications for surgery in Petrositis?

What are the surgical approaches to Petrous Apex?