Jugular foramen
A jugular foramen is one of the two large foramina in the base of the skull, located behind the carotid canal. It is formed by the temporal bone and the occipital bone. It allows many structures to pass, including the inferior petrosal sinus, three cranial nerves, the sigmoid sinus, and the posterior meningeal artery.
Structure
The jugular foramen is formed in front by the petrous portion of the [temporal bone|petrous] portion of the temporal bone, and behind by the occipital bone. It is generally slightly larger on the right side than on the left side.Contents
The jugular foramen may be subdivided into three compartments, each with their own contents.- The anterior compartment transmits the inferior petrosal sinus.
- The intermediate compartment transmits the glossopharyngeal nerve, the vagus nerve, and the accessory nerve.
- The posterior compartment transmits the sigmoid sinus, and some meningeal branches from the occipital artery and ascending pharyngeal artery.
- The smaller, anteromedial, "pars nervosa" compartment contains CN IX,, and receives the venous return from inferior petrosal sinus.
- The larger, posterolateral, "pars vascularis" compartment contains CN X, CN XI, Arnold's nerve, jugular bulb, and posterior meningeal branch of ascending pharyngeal artery.