Surgical Approaches To Cavernous Sinus

Cavernous sinus surgery has been performed increasingly in the last 2 decades because of advance in modern neuroimaging techniques, new surgical anatomy knowledge and surgical technologies. We reviewed the surgical approaches to cavernous sinus and surgical anatomy. Extradural approach to cavernous sinus has represented a refinement of the original work performed on this topic by Parkinson, Dolenc, Hakba, and other enthusiastic neurosurgeons. Surgical access to cavernous sinus has traditionally been accomplished through pterinal, subtemporal, orbitozygomatic intradural or extradural, or combined intra-extradural approach. Extradural approach includes craniotomy with or without resection of zygomatic arch, exposure of superior orbital fissure and skull base foramina, anterior clinoidectomy, unroofing of optic canal, dissection of lateral wall and entire cavernous sinus. And intradural approach has more procedure of dural incision and exposure of cranial nerves, internal carotid artery and its branches. The most important part of extradural procedure is to identify and dissect the cleavage plane between the temporal dura and the deep layer of lateral wall of cavernous sinus. The other significant aspects of dissection are anterior clinoidectomy and proper orientation while dissecting the dura matter of superior orbital fissure to avoid damage to nerve and vessel. The cranial nerves in lateral wall of cavernous sinus have neural sheath which are probably well protected from mechanical injury during surgery. It is also important to maintain vascular supply for cranial nerves to avoid injury during dissection. The advancing interventional technique is competing with direct surgical management of vascular lesion of cavernous sinus. Also the same may be applied to neoplastic lesions involving cavernous sinus, as radiosurgery like gamma knife is competing with surgical treatment. However, with improved knowledge and surgical techniques, most of lesions in cavernous sinus can be removed without additional neurological deficits.