Lymph Node Distribution Lymphatic Chains

The lymphatic system of the neck consists of a network of lymph nodes intimately connected by lymphatic channels. For teaching purposes, two major lymphatic networks may be considered in the neck, a superficial and a deep web.

Superficial Lymphatics

The superficial lymphatics of the head and neck drain the skin into the superficial lymph nodes located around the neck and along the external and anterior jugular veins. Superficial lymphatics include the submental, submandibular and facial, external jugular, anterior jugular, occipital, mastoid, and parotid groups (Fig. 2-4).

The submental nodes, usually two or three in number, lie in a midline triangular space bounded by the anterior bellies of the digastric muscles and the hyoid bone. They drain the skin of the chin, the skin and mucous membrane of the central portion of the lower lip and jaw, the floor of the mouth, and the tip of the tongue. These nodes drain into the submandibular chain or directly into the deep cervical chains.

The submandibular nodes are located along the inferior border of the horizontal ramus of the mandible. They usually lie over the submandibular gland although intracapsular nodes are also possible. The submandibular chain, along with some inconstant small facial nodes, drain the skin and mucous membrane of the nose, medial portion of the eyelid, cheek, upper lip, lateral part of the lower lip, gums, and anterior third of the lateral border of the tongue. These nodes drain into the transverse cervical and deep cervical chains.

The external jugular nodes are located between the lower parotid nodes and the midportion of the sternocleidomastoid muscle, along the external jugular vein. They drain the lower part of the ear and the parotid gland into the superior deep cervical chain.

The anterior jugular nodes are located on the anteroinferior portion of the neck, parallel to the anterior jugular vein. They drain the infrahyoid area toward the inferior deep jugular chain.

The occipital nodes drain the skin of the occipital region and part of the superficial and deep lymphatics of the nape.

The mastoid nodes are located over the mastoid process and drain the ear, external auditory canal, and skin of the temporal region.

The parotid group includes both superficial and deep nodes. The superficial nodes are located over the external surface of the parotid gland, whereas the deep nodes are intraglandular and accompany the intraparotid course of the retromandibular and external jugular. The parotid nodes drain the skin of the temporal and frontal area, eyelid, auricle, middle ear, parotid, and the mucous surface of the nasal cavity.

Deep Lymphatics

The deep lymphatics drain the mucous membranes of the upper aerodigestive tract, along with organs such as the thyroid and larynx, into the deep cervical lymph node chains. These include the internal jugular, spinal accessory, transverse cervical, retropharyngeal, and deep anterior lymphatic chains (Fig. 2-5).

The internal jugular chain is formed by a variable number of lymph nodes—between 30 and 60 — located along the internal jugular vein. The most posterior and smaller nodes are located over the splenius, levator scapulae, and scalene muscles, whereas the anterior nodes are in close relation with the anterior wall of the internal jugular vein. The posterior nodes drain the skin of the back of the head and receive efferent vessels from the occipital and mastoid nodes, as well as cutaneous and muscular tributaries from the neck. The anterior nodes drain the superficial and deep structures of the anterior part of the head and neck, both directly and indirectly.

Lymph Node Distribution
Figure 2-4 Superficial lymphatics of the neck. sme, submental; sma, submandibular; f, facial; ej, external jugular; aj, anterior jugular; o, occipital; m, mastoid; p, parotid.

Figure 2-5 Deep lymphatics of the neck. IJ, internal jugular chain; SA, spinal accessory chain; TC, transverse cervical chain; dn, Delphian node.

Figure 2-5 Deep lymphatics of the neck. IJ, internal jugular chain; SA, spinal accessory chain; TC, transverse cervical chain; dn, Delphian node.

Lymph Node Distribution

At the intersection between the digastric muscle and the internal jugular vein there is a constant prominent node, known as the jugulodigastric or KUttner's node. It drains the base of the tongue and the palatine tonsil. Another prominent node, the juguloomohyoid or Poirier's node, is located farther down at the crossing of the omohyoid muscle with the internal jugular vein. It receives lymph flow coming from the tongue and submental region. The nodes of the lower part of the internal jugular chain are less constant and participate also in the drainage of noncervical adjacent structures.

For practical purposes, the internal jugular chain may be divided into an upper and a lower part, with the dividing line located at the crossing of the omohyoid muscle with the carotid sheath.

The spinal accessory chain follows the spinal accessory nerve in the upper part of the posterior triangle and merges with the transverse cervical chain beneath the trapezius muscle. It receives lymph from the occipital and mastoid areas.

The transverse cervical chain runs along the transverse cervical vessels. It receives efferent vessels from the spinal accessory chain and from the lateral part of the neck.

The retropharyngeal nodes are located at the lateral portion of the parapharyngeal space. They drain the nasal cavity, soft palate, paranasal sinuses, middle ear, nasopharynx, and oropharynx.

The deep anterior chain includes the prelaryngeal (Delphian) node, the pretracheal, and the paratracheal nodes. They drain the subglottis, the trachea, and the thyroid gland. This chain is connected with the internal jugular chain.

Major Lymph Ducts

Both, the superficial and the deep lymphatic system initially drain in the nearest lymph nodes and then proceed to more central nodes. At the base of the right side of the neck, the jugular trunk (which collects all the lymph from one side of the head and neck), the transverse cervical trunk, and the subclavian trunk frequently join to form the right lymphatic duct. This large collector courses along the medial border of the scalene muscle and empties into the venous system at the junction of the right internal jugular vein and the right subclavian vein.

The left thoracic duct begins in the abdomen, passes through the thoracic region, and emerges in the root of the left side of the neck between the common carotid and subclavian arteries. It then arches above the subclavian artery and in front of the vertebral artery and thyrocervical trunk, to pass behind the carotid sheath between the internal jugular vein and the anterior scalene muscle. The thoracic duct empties laterally into the venous system at the junction of the left subclavian and internal jugular veins.

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