Lymphovascular Drainage

The neck contains many lymph nodes subdivided into groups and located both superficially and deep within the neck. While individual nodes can be described with reference to adjacent anatomic structures it is common practice, particularly in oncology, to divide the node groupings in the neck into six levels (Figure 19.2).

Parotid gland and the periparotid lymph nodes

Facial node

Mandible

Sublingual gland

Submental nodes

Submandibular gland and nodes

Hyoid bone Sternocleidomastoid

Lowermost deep cervical nodes

Parotid gland and the periparotid lymph nodes

Lowermost deep cervical nodes

Lymph Nodes Near Ribs

/„-"Suboccipital nodes Retroauricular nodes Mastoid process

Posterior triangle nodes

Inferior belly of omohyoid Figure 19.1. Lymph node distribution in the lateral neck and the major salivary glands.

/„-"Suboccipital nodes Retroauricular nodes Mastoid process

Upper and lower deep cervical chain nodes

Trapezius

Posterior triangle nodes

Inferior belly of omohyoid Figure 19.1. Lymph node distribution in the lateral neck and the major salivary glands.

Tail of parotid gland

Sternocleidomastoid

Submandibular gland

Tail of parotid gland

Sternocleidomastoid

Submandibular gland

Internal jugular vein (on medial aspect of specimen)

Intermediate tendon of omohyoid

Level IV

Level V

Figure 19.2. Right radical neck dissection. Dashed lines indicate the boundaries of the cervical lymph node groups.

Internal jugular vein (on medial aspect of specimen)

Intermediate tendon of omohyoid

Level IV

Level V

Figure 19.2. Right radical neck dissection. Dashed lines indicate the boundaries of the cervical lymph node groups.

Level I:

This group consists of the nodes within the submental and digastric triangles and is also known as the submandibular group. In practice, the submandibular salivary gland is included in the specimen when lymph nodes in this level are resected.

Level II:

Level II nodes represent the upper jugular group and consist of the nodes around the upper third of the internal jugular vein (IJV) and the adjacent spinal accessory (XIth) nerve. They extend from the level of the carotid bifurcation (approximating to the superior border of the thyroid cartilage) to the base of the skull. The posterior boundary of this group is the posterior border of the sternocleidomastoid muscle and the anterior boundary is the lateral border of the sternohyoid muscle. The tail of the parotid gland is often included when nodes from this group are resected.

Level III:

This group of lymph nodes corresponds to the middle jugular group and consists of lymph nodes located around the middle third of the IJV. They extend from the carotid bifurcation to the intermediate tendon of omohyoid, where it crosses the IJV. The posterior boundary is the posterior border of the sternocleidomastoid muscle and the anterior boundary is the lateral border of the sternohyoid muscle.

Level IV:

This group of lymph nodes, also known as the lower jugular group, consists of nodes located around the lower third of the IJV extending from the intermediate tendon of omohyoid where it crosses the IJV to the clavicle below. The posterior boundary is the posterior border of the sternocleidomastoid muscle while the anterior boundary is the lateral border of the sternohyoid muscle. Lymph nodes within Levels II, III and IV correspond to the jugular group or deep cervical chain of lymph nodes. They tend to be regarded as subdivisions of a functional unit rather than as distinct groups in their own right.

Level V:

Lymph nodes in this group, also known as the posterior triangle group, comprise the lymph nodes located along the lower half of the spinal accessory (XIth) nerve and represent the lymph nodes in the occipital triangle. The anterior boundary is the posterior border of the sternocleidomas-toid muscle, the posterior boundary is the anterior border of trapezius with the clavicle below.

Level VI:

Lymph nodes in this group, also known as the anterior compartment group, comprise the nodes surrounding the midline structures of the neck extending from the level of the hyoid bone above to the suprasternal notch below. On each side, the lateral boundary is the medial border of the carotid sheath. Individual groups of lymph nodes within this compartment are the perithyroid nodes, the paratracheal nodes and the precricoid nodes.

Other groups of lymph nodes within the neck are also recognized and include the suboccipital, periparotid, retropharyngeal groups and the buccal lymph node.

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