Cerebellar abscess complicating chronic suppurative otitis media: An unusual route of intracranial spread

Otogenic brain abscess is a rare but life-threatening complication of chronic suppurative otitis media. It usually develops by direct spread through bony erosion of the tegmen tympani or Trautmann triangle, or by thrombophlebitis of the sigmoid sinus. Spread along the anatomical course of the seventh and eighth cranial nerves has been described only once before. We report a 50-year-old woman with moderate intellectual disability living in residential care with long-standing hearing impairment and intermittent ear discharge, who developed sudden ataxia and right peripheral facial palsy 4 days before admission. Magnetic resonance imaging showed 2 ring-enhancing lesions with central restricted diffusion in the right middle cerebellar peduncle, together with inflammatory change along the right internal auditory canal and along the facial and vestibulocochlear nerves. Computed tomography of the temporal bones demonstrated cholesteatomatous erosion with dehiscence of the tympanic segment of the facial nerve canal and erosion of the lateral cochlear margin, without any defect of the tegmen tympani or Trautmann triangle. The patient was managed conservatively and underwent planned radical tympanomastoidectomy after 6 weeks, at which multiple wooden fragments were retrieved from the tympanic cavity. Follow-up imaging showed regression of both lesions without neurosurgical drainage.