A rare anatomical variation in foramen of Vesalius: A useful guide for maxillofacial surgeons

Background: Foramen of vesalius is an inconstant foramen that gives passage to an emissary vein that connects pterygoid venous plexus with cavernous sinus. It lies in the anteromedial side of the foramen ovale. Foramen ovale allows the passage for the mandibular branch of trigeminal nerve, the main site for the trigeminal rhizotomy. The presence and description of anatomical variations about the foramen of Vesalius is important during the surgical procedure on the trigeminal nerve which may injure the emissary vein in the foramen leading to intracranial bleeding. Objectives: The aim of the present study is to report the presence and to enlighten the anatomical variations of foramen vesalius which may serve as a guideline for surgeons. Methods: The study was conducted on 100 dry adult human skulls collected from the department of anatomy at Panimalar medical college hospital & research institute Chennai. The skulls were viewed both extracranially and intracranially to identify the presence of foramen of vesalius. The presence and variation of the foramen was noted and discussed. Result: A total of about 200 sides of 100 skulls were studied. Among them 20% of the skull showed presence of foramen of Vesalius bilaterally, 25% unilaterally and one particular skull showed doubled opening on the left side with the presence of a bony septum. This is a rare variation which was less documented in the literature. Conclusion: The knowledge of variations in foramen of Vesalius may help the surgeons for safer planning and execution of the trigeminal rhizotomy technique