Respective indications for orbital rim, zygomatic arch and orbito-zygomatic osteotomies in the surgical approach to central skull base lesions. Critical, retrospective review in 146 cases.

Abstract

Orbital Rim (ORo) Zygomatic Arch (ZAo) and Orbito-Zygomatic (OZo) osteotomies can be useful adjuncts to the classical Fronto-Pteriono-Temporal craniotomy in facilitating the exposure of deep seated skull base lesions, sparing brain retraction injuries. Based on a review of 146 "operated" cases, the authors suggest their guidelines for patient selection for each of these osteotomies. 146 lesions (100 central skull base tumors, 29 deep vascular lesions and 17 mesial temporal epileptogenic foci) were surgically treated by the senior author between 1988-1999 using ORo (59 cases), ZAo (12 cases) and OZo (75 cases). The lesion were radically cured in 85% of the cases. A retrospective critical analysis of patients' records by an independent observer evaluated: 1)--the usefulness and the appropriateness of the performed osteotomy for obtaining an optimal approach to the lesion and 2)--morbidity related to the osteotomy and to brain retraction. In only one case, the osteotomy (ORo) was found not to be useful. An other 17 patients who underwent OZo would have benefited from a reduced osteotomy (ORo in 15 cases, ZAo in 2 cases). In another case an ORo was found insufficient for an effective exposure of the lesion. Osteotomy-related morbidity rate was 10.2% (15 patients), mostly due to transient Temporo Mandibular Joint dysfunction. In spite of an appropriate approach, 12 patients (8.2%) showed neurological deficits (temporary) and/or CT manifestations attributable to brain retraction. The additional osteotomies were found useful and relatively safe in facilitating the exposure of most of the lesions in this series. A target (rather than pathology) and surgical axis oriented list of indications for ORo, ZAo and OZo is given.