The internal jugular vein is a paired

jugular vein The jugular veins are veins that take deoxygenated blood from the head back to the heart via the superior vena cava. The internal jugular vein descends next to the internal carotid artery and continues posteriorly to the sternocleidomastoid mu ...

that collects blood from the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...

and the superficial parts of the

face The face is the front of an animal's head that features the eyes, nose and mouth, and through which animals express many of their emotions. The face is crucial for human identity, and damage such as scarring or developmental deformities may aff ...

and neck. This vein runs in the

carotid sheath The carotid sheath is an anatomical term for the fibrous connective tissue that surrounds the vascular compartment of the neck. It is part of the deep cervical fascia of the neck, below the superficial cervical fascia meaning the subcutaneous adip ...

with the

common carotid artery In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
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 right ...

. It begins in the posterior compartment of the

jugular foramen 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. It is formed by the temporal bone and the occipital bone. It allows many structures to pass, including the ...

, at the base of the

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

. It is somewhat dilated at its origin, which is called the ''superior bulb''. This vein also has a common trunk into which drains the anterior branch of the

retromandibular vein The retromandibular vein (temporomaxillary vein, posterior facial vein) is a major vein of the face. Anatomy Origin The retromandibular vein is formed by the union of the superficial temporal and maxillary veins. Course It descends in th ...

, the

facial vein The facial vein (or anterior facial vein) is a relatively large vein in the human face. It commences at the side of the root of the nose and is a direct continuation of the angular vein where it also receives a small nasal branch. It lies behind t ...

, and the

lingual vein The lingual veins begin on the dorsum, sides, and under surface of the tongue, and, passing backward along the course of the lingual artery, end in the internal jugular vein. The vena comitans of the hypoglossal nerve (ranine vein), a branch of co ...

. It runs down the side of the neck in a vertical direction, being at one end lateral to the internal carotid artery, and then lateral to the

common carotid artery In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
subclavian vein to form the

brachiocephalic vein The left and right brachiocephalic veins (previously called innominate veins) are major veins in the upper chest, formed by the union of each corresponding internal jugular vein and subclavian vein. This is at the level of the sternoclavicular j ...

(innominate vein); a little above its termination is a second dilation, the ''inferior bulb''. Above, it lies upon the

rectus capitis lateralis The rectus capitis lateralis, a short, flat muscle, arises from the upper surface of the transverse process of the atlas, and is inserted into the under surface of the jugular process of the occipital bone. Additional images File:Rectus capitis ...

, behind the internal carotid artery and the nerves passing through the

. Lower down, the vein and artery lie upon the same plane, the

glossopharyngeal 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. B ...

and

hypoglossal The hypoglossal nerve, also known as the twelfth cranial nerve, cranial nerve XII, or simply CN XII, is a cranial nerve that innervates all the extrinsic and intrinsic muscles of the tongue except for the palatoglossus, which is innervated by ...

nerves passing forward between them. 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 right ...

descends between and behind the

vein Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated b ...

and the

artery An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pul ...

in the same sheath (the

), and the accessory runs obliquely backward,

superficial Superficial may refer to: *Superficial anatomy, is the study of the external features of the body *Superficiality, the discourses in philosophy regarding social relation *Superficial charm, the tendency to be smooth, engaging, charming, slick and ...

or deep to the vein. At the root of the neck, the ''right internal jugular vein'' is a little distance from the

common carotid artery In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
subclavian artery, while the ''left internal jugular vein'' usually overlaps the common carotid artery. The left vein is generally smaller than the right, and each contains a pair of

valves A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fitting ...

, which exist about 2.5 cm above the termination of the vessel.

Variation

In 9–12% of the Western population, the size, shape or course of the internal jugular vein is abnormal. Variants identified including veins markedly smaller, or not functionally present. The mean diameter is 10 mm, but may range between 5 and 35 mm.

Tributaries

Inferior petrosal sinus The inferior petrosal sinuses are two small sinuses situated on the inferior border of the petrous part of the temporal bone, one on each side. Each inferior petrosal sinus drains the cavernous sinus into the internal jugular vein. Structure The ...

Pharyngeal vein The pharyngeal veins begin in the pharyngeal plexus on the outer surface of the pharynx, and, after receiving some posterior meningeal veins and the vein of the pterygoid canal, end in the internal jugular. They occasionally open into the facial ...

Common facial vein The facial vein usually unites with the anterior branch of the retromandibular vein to form the common facial vein, which crosses the external carotid artery and enters the internal jugular vein at a variable point below the hyoid bone. From ne ...

Lingual vein The lingual veins begin on the dorsum, sides, and under surface of the tongue, and, passing backward along the course of the lingual artery, end in the internal jugular vein. The vena comitans of the hypoglossal nerve (ranine vein), a branch of co ...

Superior thyroid vein The superior thyroid vein begins in the substance and on the surface of the thyroid gland, by tributaries corresponding with the branches of the superior thyroid artery, and ends in the upper part of the internal jugular vein. It receives the supe ...

Middle thyroid vein The middle thyroid vein ( la, vena thyreoidea media) collects the blood from the lower part of the thyroid gland, and after being joined by some veins from the larynx and trachea, ends in the lower part of the internal jugular vein. Clinical featu ...

Occipital vein The occipital vein is a vein of the scalp. It originates from a plexus around the external occipital protuberance and superior nuchal line to the back part of the vertex of the skull. It usually drains into the internal jugular vein, but may al ...

(sometimes)

Clinical relevance

The jugular veins are relatively superficial and not protected by tissues such as

bone A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...

cartilage Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck an ...

. This makes them susceptible to damage. Due to the large volumes of blood that flow through the jugular veins, damage to the jugulars can quickly cause significant blood loss, which can lead to hypovolæmic shock and then death if not treated.

Jugular venous pressure

As there is one pair of valves between the

right atrium The atrium ( la, ātrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves. There are two at ...

of the heart and the internal jugular, blood can flow back into the internal jugular when the pressure in the atrium is sufficiently high. This can be seen from the outside, and allows one to estimate the pressure in the atrium. The pulsation seen is called the jugular venous pressure, or JVP. This is normally viewed with the patient at 45 degrees turning his/her head slightly away from the observer. The JVP can be raised in a number of conditions: *

right ventricular A ventricle is one of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the upper ...

failure (

heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, a ...

), *

tricuspid stenosis Tricuspid valve stenosis is a valvular heart disease that narrows the opening of the heart's tricuspid valve. It is a relatively rare condition that causes stenosis (increased restriction of blood flow through the valve). Cause Causes of tricusp ...

tricuspid regurgitation Tricuspid regurgitation (TR), also called tricuspid insufficiency, is a type of valvular heart disease in which the tricuspid valve of the heart, located between the right atrium and right ventricle, does not close completely when the right ventr ...

cardiac tamponade Cardiac tamponade, also known as pericardial tamponade (), is the buildup of fluid in the pericardium (the sac around the heart), resulting in compression of the heart. Onset may be rapid or gradual. Symptoms typically include those of obstructi ...

The JVP can also be artificially raised by applying pressure to the liver (the

hepatojugular reflux The abdominojugular test, also known as abdominojugular reflux (AJR), is a physical examination test useful in diagnosing right ventricle dysfunction, particularly right ventricular failure. AJR is a test for measuring jugular venous pressure (J ...

). This method is used to locate the JVP and distinguish it from the carotid pulse. Unlike the carotid pulse, the JVP is impalpable.

Catheterization

As the internal jugular is large, central and relatively superficial, it is often used to place

central venous lines A central venous catheter (CVC), also known as a central line(c-line), central venous line, or central venous access catheter, is a catheter placed into a large vein. It is a form of venous access. Placement of larger catheters in more centra ...

. Such a line may be inserted for several reasons, such as to accurately measure the central venous pressure or to administer fluids when a line in a peripheral vein would be unsuitable (such as during resuscitation when peripheral veins are hard to locate). Because the internal jugular rarely varies in its location, it is easier to find than other veins. However, sometimes when a line is inserted the jugular is missed and other structures such as the carotid artery, lung or the

(CN X) are punctured, and damage is caused to these structures.

Additional images

File:Gray480.png, Diagram showing completion of development of the parietal veins. File:Venenwinkel.png, The venæ cavæ and azygos veins, with their tributaries. File:Gray1174.png, The thyroid gland and its relations.

References

{{Authority control Veins of the head and neck