Anatomy of the inferior petro‐occipital vein and its relation to the base of the skull: Application to surgical and endovascular procedures of the skull base

Abstract

Although the inferior petro-occipital vein has been recently used for vascular access to the cavernous sinus, few detailed descriptions of its anatomy are in the literature. We aimed to investigate the morphology and relationships of this vessel. Twelve latex-injected cadaveric heads (24 sides) were dissected to identify the inferior petro-occipital vein and anatomic details documented. The petro-occipital vein was identified on 83.3% of sides. Generally this vein united the internal carotid venous plexus to the superior jugular bulb. However, on 10% of sides, the anterior part of this vein communicated directly with the cavernous sinus, and on 15%, the posterior vein drained into the inferior petrosal sinus at its termination into the superior jugular bulb. The petro-occipital vein was separated from the overlying inferior petrosal sinus by a thin plate of bone. On 40% of sides, small venous connections were found between these two venous structures. The vein was usually larger if a nondominant transverse sinus was present. The overlying inferior petrosal sinus was smaller in diameter when an underlying inferior petro-occipital vein was present. On 20% of sides, the posterior aspect of the vein communicated with the hypoglossal canal veins. On three sides, diploic veins from the clivus drained into the inferior petro-occipital vein. The inferior petro-occipital vein is present in most humans. This primarily extracranial vessel communicates with intracranial venous sinuses and should be considered an emissary vein. Knowledge of this vessel's exact anatomy may be useful to cranial base surgeons and endovascular specialists.

Microsurgical Anatomy of the Inferior Petroclival Vein and its Relation to Surrounding Structures: A Cadaveric and Radiological Study

“…They also investigated the presence, length, width, and connections of the vein. According to their report, 9 the vein was present on 83.3% of sides. They reported that the rostral end of the vein communicated with the venous plexus around the internal carotid artery in 90% of cases and directly with the cavernous sinus in the remaining 10% of cases.…”

“…They reported that the rostral end of the vein communicated with the venous plexus around the internal carotid artery in 90% of cases and directly with the cavernous sinus in the remaining 10% of cases. 9 They found that the vein drained into the superior jugular bulb in 85% of cases and into the inferior petrosal sinus at its termination into OPERATIVE NEUROSURGERY…”

“…Few cadaveric studies have mentioned the IPV, [4][5][6]9 probably because of both the difficulty in dissecting the vein and because it courses parallel to the well-known inferior petrosal sinus. Several authors from the late Dr Albert L. Rhoton Jr's [4][5][6] laboratory at the University of Florida have elegantly dissected this vein in their reports of the microsurgical anatomy of the skull base region.…”

“…3 Although the clinical importance of this vein has increased, limited numbers of neuroradiological and cadaveric studies are available. [4][5][6][7][8][9] This lack of data is probably due to surgeons' unfamiliarity with the vein and the difficulty in dissecting it.…”

Cranial dural arteriovenous shunts. Part 1. Anatomy and embryology of the bridging and emissary veins

“…The (distal) inferior petrosal sinus has also the position and function of an emissary vein connecting the cavernous sinus with the jugular vein [32]. Part of this group is also the inferior petro-occipital vein connecting the carotid venous plexus with the anterior condylar confluence or the superior jugular bulb and running almost parallel to the inferior petrosal sinus [61,64]. Some authors have described clival EVs connected to the basilar plexus [65].…”