Craniofacial approaches to tumors of the anterior skull base.

An approach that combines extracranial and intracranial components-termed a craniofacial approach-allows en bloc extirpation of paranasal malignancies that abut or penetrate the skull base. When combined with radiotherapy, cure rates for such tumors rose from near zero in the 1950s to 39% to 86% by 2000, with the higher rates reflective of esthesioneuroblastomas, well-differentiated adenocarcinomas, vasoformative tumors, and meningiomas. Transfacial tumor access can involve a transnasal (endoscopic or with magnification loupes) exposure, a midfacial degloving, or a lateral rhinotomy, depending on tumor location and size. Adjunctive exposures for tumors penetrating the nasopharynx, pterygomaxillary fossa, or sphenoid include the lateral facial split and the mandibular swing. The standard transcranial accesses are a sub-basal variation of frontal craniotomy, which encompasses en bloc the superior orbital rims, the nasion, and the lower frontal bones; or, a frontotemporal craniotomy with mobilization of the lateral orbital rim and the zygoma.