Analytical evaluation of complex anterior approaches to the cranial base: an anatomic study.

Abstract

The purpose of the present study was to evaluate the anatomic areas of the cranial base exposed by different complex anterior approaches. Using 20 embalmed cadaveric heads, we executed five different anterior approaches, i.e., Le Fort 1 approach with splitting or down-fracturing of the hard palate, extended maxillectomy, median mandibulotomy with glossotomy, and mandibular swing transcervical approach. Each approach was performed a minimum of three times. The areas of the intra- and extracranial cranial base exposed by each approach were analytically examined by using a numerical grading system to assess the exposure of major anatomic and neurovascular structures. Good exposure of the midline compartment of the cranial base was provided by the median mandibulotomy with glossotomy and by the Le Fort 1 approach with splitting of the hard palate, whereas the mandibular swing transcervical and extended maxillectomy approaches provided good exposure of the lateral compartment of the cranial base. Use of the numerical grading system allowed quantification of the exposure afforded by each approach, with respect to the different compartments (midline and lateral) of the intra- and extracranial cranial base, highlighting the differences among the approaches examined.