Diagnosis and management of primary tumors of the petrous apex.

Five patients with primary tumors of the petrous apex were diagnosed and treated between the years 1968 to 1974; two had congenital epidermoids, two had chondromyxosarcomas and one had neurofibroma. The embryological development of the foramen lacerum and the pattern of expansion of these primary tumors support the contention that these three categories of tumors arise in the foramen lacerum. Knowledge of the structures surrounding the foramen lacerum can provide a guide to early diagnosis of petrous apex tumors. Since these tumors cannot be completely removed, the goal of surgery is to obtain histological diagnosis and to produce permanent fistulization of the petrous apex. Although there are several recommended surgical approaches to the petrous apex, the transmastoid-translabyrinthine procedure was used in this series.