A jugular foramen is one of the two (left and right) large
foramina (openings) in the
base of the skull
The base of skull, also known as the cranial base or the cranial floor, is the most inferior area of the skull. It is composed of the endocranium and the lower parts of the calvaria.
Structure
Structures found at the base of the skull are for ...
, located behind the
carotid canal
The carotid canal is a passageway in the temporal bone of the skull through which the internal carotid artery enters the middle cranial fossa from the neck.
Structure
The carotid canal is located within the middle cranial fossa, at the petrous ...
. It is formed by the
temporal bone
The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebral cortex.
The temporal bones are overlaid by the sides of the head known as the temples, and house the structures of the ears. ...
and the
occipital bone
The occipital bone () is a 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 overlies the occipital lobes of the cer ...
. 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
The sigmoid sinuses (sigma- or s-shaped hollow curve), also known as the , are venous sinuses within the skull that receive blood from posterior dural venous sinus veins.
Structure
The sigmoid sinus is a dural venous sinus situated within the ...
, and meningeal arteries.
Structure
The jugular foramen is formed in front by the
petrous portion of the
temporal bone
The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebral cortex.
The temporal bones are overlaid by the sides of the head known as the temples, and house the structures of the ears. ...
, and behind by the
occipital bone
The occipital bone () is a 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 overlies the occipital lobes of the cer ...
.
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 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, just anterior (closer to the nose) to the vagus nerve. ...
, the
vagus nerve
The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and righ ...
,
and the
accessory nerve
The accessory nerve, also known as the eleventh cranial nerve, cranial nerve XI, or simply CN XI, is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. It is classified as the eleventh of twelve pairs of cranial nerv ...
.
* The ''posterior'' compartment transmits the
sigmoid sinus
The sigmoid sinuses (sigma- or s-shaped hollow curve), also known as the , are venous sinuses within the skull that receive blood from posterior dural venous sinus veins.
Structure
The sigmoid sinus is a dural venous sinus situated within the ...
(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 poste ...
),
and some meningeal branches from the
occipital artery
The occipital artery arises from the external carotid artery opposite the facial artery. Its path is below the posterior belly of digastric to the occipital region. This artery supplies blood to the back of the scalp and sternocleidomastoid musc ...
and
ascending pharyngeal artery
The ascending pharyngeal artery is an artery in the neck that supplies the pharynx, developing from the proximal part of the embryonic second aortic arch.
It is the smallest branch of the external carotid and is a long, slender vessel, deeply se ...
.
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
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, just anterior (closer to the nose) to the vagus nerve. Be ...
, (
tympanic nerve
The tympanic nerve (Jacobson’s nerve) is a branch of the glossopharyngeal nerve found near the ear. It gives sensation to the middle ear, the Eustachian tube, the parotid gland, and Mastoid cells, mastoid air cells. It gives parasympathetic to ...
, a branch of
CN IX
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, just anterior (closer to the nose) to the vagus nerve. Be ...
), 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
The ascending pharyngeal artery is an artery in the neck that supplies the pharynx, developing from the proximal part of the embryonic second aortic arch.
It is the smallest branch of the external carotid and is a long, slender vessel, deeply se ...
.
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
See also
*
Occipitomastoid suture
References
External links
*
*
* (, )
*
UCSD
{{Authority control
Foramina of the skull