Microsurgical and Endoscopic Anatomy of the Cavernous Sinus

Abstract

Objective To describe the endoscopic and microsurgical anatomy of the cavernous sinus (CS) with focus on the surgical landmarks in microsurgical anatomy. Materials and methods Ten formalin-fixed central skull base specimens (20 CSs) with silicone-injected carotid arteries were examined through an extended endoscopic transsphenoidal approach. Fifteen formalin-fixed heads were dissected to simulate the surgical position in CS approaches. Results Endoscopic access enables identification of the anterior and posterior surgical corridors. Structures within the CS and on its lateral wall could be visualized and studied, but none of the triangular areas relevant to the transcranial microsurgical anatomy were fully visible through the endoscopic approach. Conclusion The endoscopic approach to the CS is an important surgical technique for the treatment of pathological conditions that affect this region. Correlating endoscopic findings with the conventional (transcranial) microsurgical anatomy is a useful way of applying the established knowledge into a more recent operative technique. Endoscope can provide access to the CS and to the structures it harbors.

Microsurgical Anatomy of the Inferomedial Paraclival Triangle: Contents, Topographical Relationships and Anatomical Variations

“…The inferomedial triangle is a space in the posterior wall of the cavernous sinus. Several anatomical structures of surgical importance are located within it [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. Its superior border involves the posterior petroclinoid dural fold [ 1 , 2 , 3 , 4 ].…”

“…According to the classical description by Dolenc [ 1 ], it is delineated by the posterior clinoid process (the medial point of the triangle), the dural entrance of the trochlear nerve (the superolateral point) and the dural entrance of the abducens nerve (the inferolateral point). The main contents of this triangle include such anatomical structures as the dura forming the posterior wall of the cavernous sinus, the abducens nerve (typically located in Dorello’s canal under the petrosphenoidal ligament), the petrosphenoidal (Grüber’s) ligament, the posterior genu of the internal carotid artery’s intracavernous segment and the dorsal meningeal artery, which is typically a branch of the meningohypophyseal trunk [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. Rhoton [ 2 ] stated that removing the medial half of the triangle exposes the lateral edge of the dorsum sellae and the upper end of the petroclival suture.…”

“…There are few detailed descriptions of the normal anatomy of the triangles around the cavernous sinus in the literature, and only the typical arrangement of structures within each triangle is generally shown [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. A new approach to understanding the triangles around the cavernous sinus addressing the locations and positions of the structures and their three-dimensional relationships was proposed by Chung et al [ 10 ].…”

Gross and Micro-Anatomical Study of the Cavernous Segment of the Abducens Nerve and Its Relationships to Internal Carotid Plexus: Application to Skull Base Surgery

“…However, operative procedures in this area remain challenging due to the complex anatomical relationships and difficulty of the surgical approaches. As Isolan et al [ 5 , 6 ] stressed, the CS is characterized by a unique meningeal lining and concentration of essential vascular and neural elements. The cavernous portion (C4 segment) of the internal carotid artery usually has an S-shaped course within the CS [ 7 ].…”

“…The ICA is accompanied by a network of sympathetic nerves known as the internal carotid plexus (ICP) [ 7 , 8 , 9 , 10 ]. The abducens nerve (AN) runs between the tortuous cavernous carotid siphon and the lateral wall of the CS; The oculomotor, trochlear, and ophthalmic nerves, in turn, run in the lateral wall of the CS without being in direct contact with the venous blood [ 5 , 6 , 11 , 12 , 13 ].…”