Morphometry and Variations of Foramen Vesalius: Significance in Surgical Approach to Mandibular Nerve

Address for Correspondence: Dr. K G Prakash, Professor and Head, Department of Anatomy, Azeezia Institute of Medical Sciences, Kollam, Kerala State691537, India. Phone no.: +919645216564. E-Mail: [email protected] Background: Foramen Vesalius a small inconsistent foramen in the base of skull for passage of emissary vein from pterygoid plexus of veins to cavernous sinus. Variations in incidence and morphology are reported in literature. The objective of this study as to estimate its incidence in south Indian population and to evaluate the morphometric variations. Materials and Methods: Twenty-two dry skulls belonging to department of anatomy, Azeezia Institute of Medical Sciences, Kollam was studied with respect to base of the skull foramens. Wherever the foramen Vesalius was noted, the specimens were photographed and incidence, laterality was noted. Maximum, minimum and perimeter were noted. Any difference between male and female skulls and differences in right and left side were studied for statistical significance. P<0.05 was considered as significant. Results: We found foramen Vesalius in 40.9% of 44 sides examined. Six skulls had this foramen bilaterally. Three specimens had foramen Vesalius unilaterally and six specimens had it bilaterally. Average diameter of foramen was 1.35 (±0.56) mm from extra cranial aspect. The average diameter and perimeter of foramen in males were significantly lower than females. The average distance between foramen Vesalius and foramen ovale was significantly more in females than in males. Conclusion: Foramen ovale is an inconsistent and asymmetrical foramen in base of skull near foramen ovale. Forty percent of the skulls studied had foramen Vesalius. There is significant difference measurements of right and left side foramens. Considering these variations in infratemporal fossa decreases complications while approaching mandibular nerve and trigeminal ganglion.