The forgotten lymph nodes: Review of the superficial head and neck lymphatic system

In patients with head and neck malignancy, knowledge of the lymphatic pathways relevant to tumor location is important for treatment preparation, both in radiation therapy and in surgery. The lymphatics of the head and neck area consist of superficial and deep nodes groups, which are connected by numerous small vessels, giving rise to a complex subcutaneous and deep lymphatic network. The deep cervical lymph nodes, mainly placed along the jugulo carotid vessels, have been intensively reviewed in radiology and classified by wellestablished levels. The more superficial groups, notably the occipital, parotid, mastoid, facial and superficial cervical lymph nodes groups were not well recognized in the radiology literature, probably because of their less frequent involvement in the more predominant pharyngeal and laryngeal mucosal malignancy, and seem to have been forgotten. We present a review of the anatomy of those lymph nodes groups, including their location, afferent and efferent drainage tracts accompanied by cross-sectional imaging CT examples.