Transmaxillary-transnasal approach to the anterior clivus: a microsurgical anatomical model.

Numerous procedures to expose the anterior clival region have been described, including the transoral, transcervical, transseptal-transsphenoidal, transantral, transnasal, bilateral Le Fort I maxillotomy, transbasal, transpalatal, and modifications of the Caldwell-Luc approach. Despite the large number of surgical options available, it may be necessary to have wider access to the midline skull base than these approaches provide. We have developed a microsurgical transmaxillary-transnasal approach to the anterior clivus that has been studied in both dry skull and cadaveric preparations and used clinically. The surgical technique has four stages: 1) antromaxillary; 2) nasal; 3) sphenoidal; and 4) clival. The wider access of this approach is achieved mainly by an osteotomy of the frontal process of the maxilla, which transforms the nasal cavity and the antrum into a single cavity while preserving the functional anatomy of the nose. Cosmesis is preserved by replacement of the cartilaginous nasal septum and the frontal process at the end of the procedure. The technique provides the good cosmetic results of the sublabial approaches and prevents vascular and neural injury in the same way that other anterior approaches do. This transmaxillary-transnasal technique may be used in combination with other approaches for extensive tumors.