Foramen venoso órbito cavernoso : Foramen de Warwick

Abstract

SUMMARY: The Warwick’s foramen or cavernous orbital venous foramen, is an inconstant foramen from the greater wing of the sphenoid bone, located between the superior orbital fissure and the rotundum foramen. It connects the orbit with the middle cranial fossa and/or with the pterygopalatine fossa and allows for thepassage of the inferior ophthalmic vein. The presence of the cavernous orbital venous foramen varies between 0.38 % and 0.74 % in human skulls. It is described as having a rounded or crescentic (semilunar), unilateral or bilateral shape. The objective of the present work was to demonstrate the presence and characteristics of the cavernous orbital venous foramen in dry skulls of Chilean adult individuals of both sexes. One hundred and thirty-eight adult skulls of both sexes were analyzed in search of the cavernous orbital venous foramen to determine the frequency, location, shape, size, orientation and distances with respect to the superior orbital fissure and the rotund foramen. Found foramina were photographed, explored and measured. The cavernous orbital venous foramen was present in 2.17 % of the sample, and was both unilateral (1.45 %) and bilateral (0.17 %). It had a rounded and lunate shape in 3 and 1 cases, respectively. Moreover, it was orientated towards the orbit (2 cases) and towards the pterygopalatine fossa (2 cases). It was also evidenced that when the cavernous orbital venous foramen is present, the separation between the superior orbital fissure and the rotund foramen is greater than in its absence. Our study demonstrates the presence of the cavernous orbital venous foramen in the Chilean population, with a higher frequency than described previously. The location, orientation and observed forms agree with the literature, but differ in size (in rounded shape fora-men). We could also determine that the superior orbital fissure and the rotundum foramen tend to be closer in the absence of the cavernous orbital venous foramen and, therefore, are more distant when this structure is present. This fact is not described in the literature. The results of this study are important for anatomy, ophthalmology, traumatology, imaging, surgery and human identification. Finally, and by virtue of the International Anatomical Terminology (IAT), we propose to call this structure the cavernous orbital venous foramen.