A jugular foramen is one of the two (left and right) large foramina (openings) in the base of the skull, located behind the

carotid canal The carotid canal is a passage in the petrous part of the temporal bone of the skull through which the internal carotid artery and its internal carotid (nervous) plexus pass from the neck into (the middle cranial fossa of) the cranial cavity. ...

. It is formed by the

temporal bone The temporal bone is a paired bone situated at the sides and base of the skull, lateral to the temporal lobe of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples where four of the cranial bone ...

and the

occipital bone The occipital bone () is a neurocranium, cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone lies over the occipital lob ...

. It allows many structures to pass, including the inferior petrosal sinus, three

cranial nerves Cranial nerves are the nerves that emerge directly from the brain (including the brainstem), of which there are conventionally considered twelve pairs. Cranial nerves relay information between the brain and parts of the body, primarily to and f ...

, the sigmoid sinus, and meningeal arteries.

Structure

The jugular foramen is formed in front by the petrous portion of the

, and behind by the

. It is generally slightly larger on the right side than on the left side.

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 glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper Medulla oblongata, medulla, just anterior (closer to the nose) to t ...

, the

vagus nerve The vagus nerve, also known as the tenth cranial nerve (CN X), plays a crucial role in the autonomic nervous system, which is responsible for regulating involuntary functions within the human body. This nerve carries both sensory and motor fibe ...

, and the accessory nerve. * The ''posterior'' compartment transmits the sigmoid sinus (becoming the

internal jugular vein The internal jugular vein is a paired jugular vein that collects blood from the brain and the superficial parts of the face and neck. This vein runs in the carotid sheath with the common carotid artery and vagus nerve. It begins in the posteri ...

), and some meningeal branches from the occipital artery and ascending pharyngeal artery. An alternative imaging based subclassification exists, delineated by the jugular spine which is a bony ridge partially separating the jugular foramen into two parts: * The smaller, anteromedial, "pars nervosa" compartment contains CN IX, ( tympanic nerve, a branch of 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 (or the auricular branch of CN X involved in the Arnold's reflex, where external auditory meatus stimulation causes cough), jugular bulb, and posterior meningeal branch of ascending pharyngeal artery.

Clinical significance

Obstruction of the jugular foramen can result in jugular foramen syndrome.

Additional images

File:Base of skull 18.jpg, Jugular foramen Image:Gray193.png, Base of the skull. Upper surface. Image:Skull_foramina_labeled.svg

References

External links

* * * (, ) *
UCSD
{{Authority control Foramina of the skull Otorhinolaryngology Neurosurgery

Structure

Contents

Clinical significance

Additional images

See also

References

External links