Petrous apicitis The most medial and anterior portion of the temporal bone 30% of temporal bones with pneumatization of the petrous apex Proximity to the posterior and middle cranial fossae A=90 LevPetrous apicitis ◼ The most medial and anterior portion of the temporal bone ◼ 30% of temporal bones with pneumatization of the petrous apex ◼ Proximity to the posterior and middle cranial fossae