Petrosal Artery in Middle Fossa Approach: Rare Entity

Abstract Purpose In middle fossa approach, middle meningeal artery is sacrified during the surgery but, sacrification of this artery sometimes disrupts the supply of the ganglion geniculate, causing facial nerve palsy. The aim of this study is to show the petrosal artery that originates from the middle meningeal artery and feeds the ganglion geniculate, which can be seen very rarely in surgical and cadaver dissections. Method In Cerrahpaşa Faculty of Medicine, Micro-Endoneurosurgery and Neuroanatomy Laboratory, the middle fossa approach was applied with the help of a microscope on 2 silicone-injected cadavers with classical methods. Each stage of the dissections was 3D photographed. Result After temporal craniotomy, the foremen spinosum and the middle meningeal artery (OMA) were reached by retraction of the temporal lobe. Mandibular and maxillary branches of trigeminal nerve were exposed after going on dissecting anterior to foramen spinosum. Sometimes these structures may be covered with bone tissue and light drilling may be required for dissection. After greater petrosal nerve and ganglion geniculate are exposed, arcuate eminence is pierced approximately 60 degrees medially, and internal acoustic canal is opened superiorly and 7–8. nerve bundle is reached. Conclusion OMA gives rise to the petrosal artery, a branch that supplies the ganglion geniculate. If the OMA is to be sacrificed during surgery, this should be done above the petrosal artery level so that the arterial supply of the ganglion geniculate is not impaired. Preservation of the petrosal artery is important in neurosurgery practice.