Malignant otitis externa in a diabetic patient spreads beyond the cartilaginous external auditory canal into the parotid space and skull base. Which anatomical feature of the cartilaginous canal permits this extension?

• A Foramen of Huschke
• B Tympanomastoid fissure
• C Petrotympanic fissure
• D Fissures of Santorini ✓

Explanation

The fissures of Santorini are vertical gaps in the cartilage of the cartilaginous external auditory canal filled with fibrous tissue. They provide natural pathways for infection and tumour to spread to the parotid gland, infratemporal fossa and skull base, explaining the aggressive behaviour of malignant otitis externa. The petrotympanic fissure transmits the chorda tympani within the temporal bone and is unrelated to canal cartilage.

Reference: Dhingra's Diseases of Ear, Nose and Throat, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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