Skull base lesions: a classification and surgical approaches.

An anatomic classification of lesions affecting the skull base is proposed according to which this region can be divided into a midline compartment and two lateral compartments: a petrotemporal and an infratemporal. The majority of lesions studied radiographically in 56 patients were confined to one of these anatomic subdivisions. The advantages of such a classification are discussed. The surgical approaches to these compartments and to the anterior middle and posterior cranial fossae are described relative to the lesions we have encountered.