A set of veins drains blood from the brain, neck, and face and returns it to the heart through the superior vena cava. This set of veins is called the jugular vein. There are two types of this vein. In this article, we will study the different types of this vein and understand their anatomies and functions elaborately.
What is Jugular Vein?
The jugular vein is the set of blood vessels that carry deoxygenated blood from the tissues of the brain, neck, and face and deliver it to the superior vena cava. The prime function of these veins is to collect and carry deoxygenated blood to the heart for purification. There are two different types of jugular veins present in the human anatomy.
Anatomy of Jugular Veins
There are two different sets of jugular veins running down the neck to the heart. The jugular vein anatomy suggests that these veins run right to drain the content into the subclavian veins.
The internal jugular vein joins the subclavian veins to form brachiocephalic veins. These veins are present at the right and left of our neck. These veins then merge to form the superior vena cava and reach the heart.
Types of Jugular Veins
The jugular vein anatomy suggests the following types of blood vessels.
1.Internal Jugular Vein
The formation of the internal jugular vein results from the anastomosis or connection between the common facial vein and sigmoid sinus, the vein arising from the dura mater of the brain. It runs along with the common carotid artery and is positioned right beside the vagus nerve within the carotid sheath. It is the main drainage vein that collects and carries the metabolic contents and respiratory gases from the skull and face.
It is made of three layers.
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Tunica Adventitia – It is the outermost layer of this vein and the thickest among the three. It is made of loose connective tissues that connect with the rest of the surrounding tissues.
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Tunica Media – The middle layer of this vein wall is made of collagen, smooth muscles and elastic fibres.
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Tunica Intima – It is the innermost and the thinnest layer in the vein wall. It forms the internal lumen of the internal jugular vein. It is made of elastic membranes and connective tissues.
2.External Jugular Vein
The external jugular vein runs parallel and superficial to the sternocleidomastoid. It is one of the longest muscles present in both sides of the neck that helps in turning the head. Its prime function is to drain the content of tissues from the parotid gland, scalp, and submaxillary region (facial sides) and then return it to the heart.
Consider the internal jugular vein anatomy to understand the structure and composition of the external jugular vein walls. The external jugular vein formation occurs due to the confluence of the posterior retromandibular vein and the posterior auricular vein.
3.Anterior Jugular Vein
There is another vein that runs laterally to the cricothyroid ligament. Its origin is close to the hyoid bone and is formed by the confluence of superficial veins arising from the submandibular region. It eventually opens in the terminating portion of the external jugular vein.
Functions of the Jugular Veins
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External Jugular Vein Function
The jugular vein function of this type is draining blood from the tissues in the neck region. It also carries blood out of the head and face through different routes and eventually pours it in the superior vena cava.
The superficial part of this vein draws deoxygenated blood from the parotid gland. It is the largest salivary gland in human beings. It also draws deoxygenated blood from the facial sides and scalp.
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Internal Jugular Vein Function
Its prime function is to maintain a seamless path for the flow of deoxygenated blood to the superior vena cava from the brain, head, and neck. It also connects with the facial vein, pharyngeal vein, inferior petrosal sinus, lingual vein, superior and middle thyroid veins to drain deoxygenated blood from the corresponding organs and tissues.
Another function of this vein is to stop the backflow of blood due to the presence of a valve. It stops deoxygenated blood from flowing back to the brain avoiding internal haemorrhage in this organ.
Significance of Jugular Veins
Now that we know the functions of the jugular veins, we can clearly understand their significance in the circulatory system. This vein is the measurement platform of vein pressure that helps doctors to diagnose any anomaly in the lungs and heart.
A distinct waveform is maintained by this vein’s pressure that helps in diagnosing the diseases in the lungs and heart. The rhythmic contraction and relaxation of the heart ventricles and auricles create this pressure waveform. Hence, it is an indirect observation medium that helps to detect anomalies and diseases.
This is an elaborate description of the jugular vein location, anatomy, and functions. It is better to study these sections using a jugular vein diagram and correlate their functions. The formation of these veins due to the union of various smaller veins will become easier to distinguish and understand.