A patient with atticoantral CSOM has a cholesteatoma eroding the tegmen tympani. The structure immediately superior to the tegmen tympani that is at risk of involvement is:

• A Middle cranial fossa dura and temporal lobe ✓
• B Cavernous sinus
• C Posterior cranial fossa and sigmoid sinus
• D Superior petrosal sinus

Explanation

The tegmen tympani is a thin plate of bone forming the roof of the middle ear, separating it from the middle cranial fossa. Cholesteatoma eroding the tegmen may cause middle cranial fossa extradural abscess, temporal lobe abscess, or meningitis. The sigmoid sinus and posterior fossa are at risk from posterior erosion. The superior petrosal sinus lies at the junction of middle and posterior cranial fossae.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.