BACKGROUND: 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. METHOD: 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. FINDINGS: 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. INTERPRETATION: 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.
BACKGROUND: 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. METHOD: 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. FINDINGS: 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. INTERPRETATION: 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.
Authors: Lili Laleva; Toma Spiriev; Iacopo Dallan; Alberto Prats-Galino; Giuseppe Catapano; Vladimir Nakov; Matteo de Notaris Journal: J Neurol Surg B Skull Base Date: 2018-09-06