A 10-year-old boy with long-standing right ear discharge develops severe retro-orbital pain and double vision. Examination shows right lateral rectus palsy with sparing of other extraocular movements. The most likely diagnosis is:

• A Cerebellar abscess compressing the sixth nerve nucleus
• B Lateral sinus thrombophlebitis with cavernous sinus extension
• C Otitic hydrocephalus
• D Gradenigo's syndrome due to apical petrositis ✓

Explanation

Gradenigo's syndrome is the classical triad of otorrhoea, ipsilateral retro-orbital pain (trigeminal involvement of the ophthalmic division in Meckel's cave) and abducens palsy, caused by inflammation extending to the petrous apex along pneumatized perilabyrinthine cells. The sixth nerve runs beneath Gruber's ligament near the apex and is affected early. Cavernous sinus thrombosis would produce multiple cranial palsies and proptosis rather than isolated sixth nerve palsy.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.