Lymph nodes of the neck, organization

1. Parajugular nodal chain, running along the internal jugular vein.

For the purpose of describing the location of a lymph node within this long chain, three separate parajugular lymph node regions may be distinguished. From an imaging point of view, the high parajugular nodes or jugulodigastric lymph nodes lie between the base of the skull and the axial level of the hyoid bone. Between the level of the hyoid bone and the cricoid cartilage lie the mid-parajugular nodes. Between the level of the cricoid cartilage and the clavicle are situated the low parajugular nodes.

2. Spinal accessory nodal chain, within the fat of the posterior neck triangle. The nodes are more or less concentrated along the accessory nerve, which runs anterior to the trapezius muscle.

3. Transverse cervical nodal chain, connects the parajugular and spinal accessory nodal chain low in the neck.

There are many lymph nodes lying outside these three major chains, such as the submental lymph nodes (between the anterior bellies of the digastric muscles), the submandibular lymph nodes in the submandibular space, the intraparotid lymph nodes (see parotid gland) and facial lymph nodes. All these nodes eventually drain into the jugulodigastric lymph nodes. There are also lymph nodes present behind the naso- and oropharynx; these retropharyngeal lymph nodes cannot be examined clinically, and imaging plays an important role in their evaluation (see retropharyngeal space).

A more refined imaging description of the neck lymph nodes is possible by using the level system of lymph node classification.

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