Microsurgical Removal of Olfactory Groove Meningiomas via the Pterional Approach

Abstract

Commonly used frontobasal approaches for microsurgical removal of olfactory groove meningiomas have certain disadvantages, such as late exposure of the neurovascular complex located dorsal to the tumor, namely, the internal carotid artery, middle cerebral artery, anterior cerebral artery, and the optic nerves. In addition, the frontal sinuses are frequently opened and there can be compression of the frontal lobes from significant spatula pressure. We report our experience with the pterional approach for these tumors in 28 patients. All patients presented with hyposmia/anosmia; 20 had personality changes and 8 had visual deficits. At surgery, after dissection of the sylvian fissure, the internal carotid artery, middle cerebral artery, anterior cerebral artery, and the homolateral optic nerve were exposed before removal of the posterior tumor parts. Reduction of focal pressure was achieved by removal of the contralateral tumor following partial resection of the falx and crista galli. Total tumor removal was obtained in all but 1 patient. One patient died of pulmonary embolism. The psychoorganic syndrome resolved in all but 1 patient; visual deficits improved in 6 patients. There were no postoperative infections. We consider the pterional approach to be superior to others for these lesions because it provides early exposure of the neurovascular complex, preservation of the frontal venous drainage, and avoidance of postoperative cerebrospinal fluid fistulae.