Intracranial microsurgical anatomy of the pterional region and Sylvian fissure: contributions of Mahmut Gazi Yaşargil

Abstract

The pterional region and Sylvian fissure are important anatomical corridors in intracranial microsurgery. Safe use of this route requires a clear understanding of skull base anatomy, meningeal layers, the Sylvian fissure, insular and opercular regions, and the surrounding arterial, venous, and cisternal structures. This narrative review integrates macroscopic and microsurgical anatomy with a focus on the pterional-transsylvian approach and its development in modern neurosurgery. Key surgical principles include stepwise Sylvian fissure dissection, identification of arachnoid planes, exposure of the middle cerebral artery and its perforators, preservation of superficial and deep venous drainage, and limitation of cerebral retraction. Particular attention is given to anatomical variations that may influence the direction and extent of dissection. Clinically, the corridor provides access to middle cerebral and anterior communicating artery aneurysms, selected internal carotid and basilar bifurcation lesions, and tumors involving the frontal, temporal, insular, and deep regions. The contribution of Mahmut Gazi Yaşargil is considered in relation to microsurgical visualization, skull base modification, natural anatomical corridors, and neurovascular preservation. Overall, the pterional-transsylvian approach illustrates how three-dimensional anatomical knowledge can guide surgical exposure while limiting unnecessary manipulation of normal neural and vascular structures. These principles remain relevant to contemporary intracranial microsurgery despite advances in imaging, navigation, and minimally invasive techniques.

Keywords

• basal cisterns
• cerebral veins
• intracranial microsurgery
• Mahmut Gazi Yaşargil
• microsurgical anatomy
• middle cerebral artery
• pterional approach
• Sylvian fissure

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