Jugular lymph trunk

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The jugular lymph trunk is a collection of lymph vessels and nodes in the neck. The jugular lymph trunks are located on either side of the neck and are responsible for draining the tissue of the head and neck. The lymph vessels of the jugular chain fight infection and cancer, but can also become a source of cancer themselves. This cancer of the lymph nodes is called lymphoma. Lymphoma can be treated with surgery, chemotherapy, or radiation.

The left trunk carries lymph fluid to the thoracic duct, the major lymphatic vessel of the body. The thoracic duct then drains into the blood circulatory system at the junction of the left subclavian vein and the jugular vein. The right trunk carries lymph fluid to a smaller duct that drains into the right subclavian vein.

Background

The lymphatic system consists of organs, ducts, and nodes[4]. Lymph nodes are rounded bodies consisting of accumulations of lymphatic tissue found at intervals in the course of lymphatic vessels[2]. Found within lymph vessels is an alkaline (basic) fluid that is typically colorless[2]. Appearance of lymph fluid, however, will vary throughout the body. For example, lymph fluid in vessels that drain the intestines will appear milky due to the presence of absorbed fats[2].

The main purpose of this watery clear fluid is to distribute immune cells throughout the body[4]. Lymphocytes (white blood cells) are the most common immune cells found in lymph fluid[4]. Aside from transporting immune cells and other factors, the vessels of the lymphatic system interact with the blood circulatory system to drain fluid from cells and tissues[4].

Anatomy

The collection of lymph vessels and nodes in the neck make up the jugular lymph trunk[4]. The “jugular chain” of the lymphatic system contains lymphatic ducts and nodes[1]. On the left side of the neck, the jugular lymph trunk drains into the thoracic duct, the main lymphatic passage draining the organs of the chest and abdomen[4]. The thoracic duct then drains into the site where the jugular vein joins the subclavian vein (under the left clavicle or collar bone)[4]. On the right, the trunk drains into a much smaller duct that drains into the right subclavian vein[1].

Many lymph nodes of the head and neck drain into the jugular lymph trunks. These nodes include the parotid nodes, submandibular nodes, submental nodes, sublingual nodes, and anterior cervical nodes[1]. The parotid nodes drain the parotid gland on the side of the face[1]. The submandibular nodes are located under the mandible (jaw bone) and drain fluid from the submandibular saliva glands[1]. The submental nodes are located directly under the chin and drain the surrounding area[1]. The sublingual nodes are located under the tongue and drain the floor of the mouth[1]. Finally, the anterior cervical nodes are located under the anterior skin of the neck and drain the anterior skin and neck[1]. (Anterior is used to describe what we would consider to be the front of the body versus posterior which describes the back.)

Complications

Nodes help to filter out infections from the head and neck and can also help to prevent the spread of cancer cells to other parts of the body[1]. Consequently, viral and bacterial infection can cause the lymph nodes to enlarge[1]. In the case of the jugular lymph nodes, dental and tonsillar (tonsil) infections can cause a swelling of the nodes[1]. Problems with the teeth, floor of the mouth, and tongue can also influence the nodes of the jugular chain[1]. If lymph vessels are removed or damaged by radiation, fluid from the surrounding tissue will have no where to drain, and swelling will ensue[1].

Cancers of the oral cavity, pharynx (back of the throat), larynx (voice box), and some skin cancers of the head and neck can drain into the lymph vessels and nodes of the neck[1]. Consequently, neck masses are typically a sign of head/neck cancer[1]. When these nodes become involved, the prognosis is generally poor because it means that the tumor has spread from its original site[1]. Also, cancers may originate in the lymph nodes of the neck themselves[1]. Cancer of the lymph nodes is called lymphoma, and malignant lymphomas are treated with radiation and/or chemotherapy[1].

A “neck dissection,” a surgical procedure in which the entire system of jugular lymph nodes is removed, is often protocol when cancer enters the nodes[3]. Dissection of the lymph nodes on the left side of the neck is more dangerous than operating on the right. The thoracic duct (into which the left jugular lymph trunk drains) has many contributing, large lymphatic vessels. These vessels are clear and have very thin walls, therefore making them susceptible to injury during surgery[3]. If one of these major lymph vessels is cut, the resulting complication is called a chyle fistula, named after the fatty lymph fluid (chyle) which the thoracic duct absorbs from the intestines[3]. A chyle fistula can heal on its own if the patient is maintained on a fat-free diet[3].

Patients who experience trauma to the neck can form a lymphocele[3]. A lymphocele is a large, cystic mass in the neck filled with lymphatic fluid[3]. To cure this problem, the cyst must be removed in its entirety and the main contributing lymph vessel must be tied off[3]. (A cyst is a closed sac or pouch with a definite wall which contains fluid or solid material[2]).

References

1. Biedlingmaier, John. (MD, FACS), Personal interview. October 26, 2008.
2. Taber, Clarence Wilbur. Taber’s Cyclopedic Medical Dictionary. 11th ed. 1969.
3. Taylor, Rodney. (MD, MSPH, FACS), E-mail interview. October 21, 2008.
4. Wolf, Jeffrey. (MD, FACS), E-mail interview. October 21, 2008. hlij