The middle fossa transpetrous approach to the anterior-superior cerebellopontine angle.

We present a new approach to the skull base, medial and superior to the internal auditory canal, for tumors involving the anterior-superior cerebellopontine angle, petrous apex, and clivus. This approach is accomplished through a middle fossa craniotomy and involves removal of the bone anterior and medial to the internal auditory canal and medial to the cochlea and carotid artery. It combines the advantages of complete tumor removal, low mortality rate, and hearing preservation.