[Surgical Anatomy of the Cavernous Sinus, Parasellar Region, and Orbit]

The cavernous sinus, para-sellar region, and orbit have intricately intertwined cranial nerves, blood vessels, and dura mater. In surgery, anatomical understanding is very important. Recognizing the location(depth)of the cranial nerves running on the lateral and upper wall of the cavernous sinus is vital and is directly linked to postoperative complications. In addition, understanding the dural ring in the clinoid segment of the internal carotid artery is important. The periosteum on the upper surface of the anterior clinoid is the distal dural ring of the internal carotid artery, and the periosteum on the lower surface is the proximal dural ring. The orbit is filled with adipose tissue and is completely different from other intracranial parts. However, understanding the anatomy from the orbital apex to the superior orbital fissure is important in the pterional approach.