Transsphenoidal and infralabyrinthine approach of the petrous apex cholesterol granuloma

Space-demanding or destructive changes in the petrous bone are often challenging differential diagnosis. Cholesterol granulomas of the petrous apex can clinically present in a combination of hearing loss, vertigo, tinnitus, chronic cephalgia, impairment of facial nerve function, neuralgic pain of the nervus trigeminus, or manifest diplopia by the nerve palsy of the nervus abducens. CT-morphologically cholesterol granulomas appear as soft-tissue density masses, which may display a discrete rim after intravenous administration of a contrast agent. The MRI, T1 as well as T2-weighted images show a strong signal in the area of the lesion. Depending on the individual anatomical conditions, the surgical access must be carefully chosen between transsphenoidal, transtemporal, infracochlear/-labyrinthine, or translabyrinthine. Here, we present the transsphenoidal and translabyrinthine access for the excision of cholesterol granulomas of the petrous apex. The different accesses are compared using a neuro-navigation-supported surgical technique with respect to its complications, drainage possibilities, outcomes, and recurrence of symptoms.