Morphological Study of Jugular Foramen.

Abstract

Jugular foramen is a large aperture in the base of the skull. It is located behind the carotid canal and is formed by the petrous part of the temporal bone and behind by the occipital bone. The jugular foramen is the main route of venous outflow from the skull and is characterised by laterality based on the predominance of one of the sides. Sigmoid sinus continues as internal jugular vein in posterior part of jugular foramen. Ligation of the internal jugular is sometimes performed during radical neck dissection with the risk of venous infarction, which some adduce to be due to ligation of the dominant internal jugular vein. It is generally said that although the Jugular foramen is larger on the right side compared to the left, its size as well as its height and volume vary in different racial groups and sexes. The foramen’s complex shape, its formation by two bones, and the numerous nerves and venous channels that pass through it further compound its anatomy. The present study was undertaken in 263(526 sides) different medical and dental institutions in Karnataka, India. Out of 263 skulls in 61.21% of cases the right foramina were larger than the left, in 13.68% of cases the left foramina were larger than the right and in 25.09% cases were equal on both sides. The jugular fossa present bilaterally in 30.79%, on the right only in 36.50% cases, on the left only in 27.37% cases and was absent in 53.23% cases.