The morphology and morphometry of the foramina of the greater wing of the human sphenoid bone.

The greater wing of the human sphenoid bone is pierced by several foramina, which contain, as a main element, the venous anastomoses between the interior of the skull and the extracranial veins. Since data concerning these foramina are scarce in the literature, studies comprising the frequency of occurrence and morphology of the foramina of the greater wing of the human sphenoid bone were undertaken on 100 macerated skulls. We found that the foramen ovale is divided into 2 or 3 components in 4.5% of cases. Moreover, the borders of the foramen ovale in some skulls were irregular and rough. This may suggest, on radiological images, the presence of morbid changes, which might be the sole anatomical variation. Concurrent with the foramen ovale are accessory foramina. The foramen of Vesalius and the cavernous foramen were present in 17% and 33% of cases, respectively. The foramen of Vesalius was always single and the cavernous foramen also occurred in multiple form. The foramen spinosus and the foramen rotundum occurred as permanent elements of the skulls studied. The mean area of the foramina measured, excluding the foramen ovale, was not considerable, which may suggest that they play a minor role in the dynamics of blood circulation in the venous system of the head.