In a patient with CSOM-safe (tubotympanic) disease, the tympanic membrane perforation is characteristically:

• A Attic (pars flaccida) with granulations and bony erosion
• B Marginal posterior with contact with the annulus
• C Subtotal with complete erosion of the fibrous annulus
• D Central (pars tensa) with intact margins and no cholesteatoma ✓

Explanation

CSOM-safe (mucosal/tubotympanic) disease is characterised by a central perforation of the pars tensa with a rim of intact tympanic membrane around the perforation, no cholesteatoma and no bony erosion. The discharge is mucoid and intermittent. In contrast, CSOM-unsafe (squamosal/atticoantral) disease has attic or marginal perforations with cholesteatoma, bony erosion, and foul-smelling discharge — hence it is 'unsafe' due to risk of intracranial complications.

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.