Petrous apex cholesteatoma.

In this chapter we have reviewed the etiology, diagnosis, and surgical treatment of petrous apex cholesteatoma. The etiology is usually congenital for those tumors arising within the apex, but acquired for lesions secondarily invading the apex. Diagnosis is primarily radiographic. CT remains an excellent modality for determining the extent of disease, whereas recent advances with MRI help in differential diagnosis. In our experience the middle fossa approach and the translabyrinthine-transcochlear approach allow the surgeon the best opportunity to effectively treat this rare and challenging tumor.