Vaginal process of sphenoid bone

The vaginal process of sphenoid bone, known as the processus vaginalis, is a flat medial extension from the upper portion of the sphenoid bone’s medial pterygoid plate. It lies between the ala of the vomer bone above and the sphenoidal process of the palatine bone beneath. This arrangement forms two passages: the vomerovaginal canal (or canalis vomerovaginalis) above the vaginal process and the palatovaginal canal (or canalis palatovaginalis) below it, also referred to as the pharyngeal canal. The former passes between the vomer and the vaginal process, while the latter lies between the vaginal process and the sphenoidal process of the palatine bone. Both passages run horizontally from the rear to the front.

The palatovaginal or pharyngeal canal links the pterygopalatine fossa with the nasopharynx, facilitating the travel of the pharyngeal branches of the maxillary artery and the pterygopalatine ganglion from the pterygopalatine fossa towards the nasopharynx. They supply the nasopharyngeal region behind the auditory tube. Compared to the vomerovaginal canal, the palatovaginal canal is more commonly found.