Lymphatic Vessels
The lymphatic vessels of the head and neck can be divided into two major groups; superficial vessels and deep vessels.
Superficial Vessels
The superficial vessels drain lymph from the scalp, face and neck into the superficial ring of lymph nodes at the junction of the neck and head.
Deep Vessels
The deep lymphatic vessels of the head and neck arise from the deep cervical lymph nodes. They converge to form the left and right jugular lymphatic trunks:
- Left jugular lymphatic trunk – combines with the thoracic duct at the root of the neck. This empties into the venous system via the left subclavian vein.
- Right jugular lymphatic trunk – forms the right lymphatic duct at the root of the neck. This empties into the venous system via the right subclavian vein.
Lymph Nodes
The lymph nodes of the head and neck can be divided into two groups; a superficial ring of lymph nodes, and a vertical group of deep lymph nodes.
Superficial Lymph Nodes
The superficial lymph nodes of the head and neck receive lymph from the scalp, face and neck. They are arranged in a ring shape; extending from underneath the chin, to the posterior aspect of the head. They ultimately drain into the deep lymph nodes.
- Occipital: There are usually between 1-3 occipital lymph nodes. They are located in the back of the head at the lateral border of the trapezius muscle and collect lymph from the occipital area of the scalp.
- Mastoid: There are usually 2 mastoid lymph nodes, which are also called the post-auricular lymph nodes. They are located posterior to the ear and lie on the insertion of the sternocleidomastoid muscle into the mastoid process. They collect lymph from the posterior neck, upper ear and the back of the external auditory meatus (the ear canal).
- Pre-auricular: There are usually between 1-3 pre-auricular lymph nodes. They are located anterior to the auricle of the ear, and collect lymph from the superficial areas of the face and temporal region.
- Parotid: The parotid lymph nodes are a small group of nodes located superficially to the parotid gland. They collect lymph from the nose, the nasal cavity, the external acoustic meatus, the tympanic cavity and the lateral borders of the orbit. There are also parotid lymph nodes deep to the parotid gland that drain the nasal cavities and the nasopharynx.
- Submental: These lymph nodes are located superficially to the mylohoid muscle. They collect lymph from the central lower lip, the floor of the mouth and the apex of the tongue.
- Submandibular: There are usually between 3-6 submandibular nodes. They are located below the mandible in the submandibular triangle and collect lymph from the cheeks, the lateral aspects of the nose, upper lip, lateral parts of the lower lip, gums and the anterior tongue. They also receive lymph from the submental and facial lymph nodes.
- Facial: This group comprises the maxillary/infraorbital, buccinator and supramandibular lymph nodes. They collect lymph from the mucous membranes of the nose and cheek, eyelids and conjunctiva.
- Superficial Cervical: The superficial cervical lymph nodes can be divided into the superficial anterior cervical nodes and the posterior lateral superficial cervical lymph nodes. The anterior nodes lie close to the anterior jugular vein and collect lymph from the superficial surfaces of the anterior neck. The posterior lateral nodes lie close to the external jugular vein and collect lymph from superficial surfaces of the neck.
Deep Lymph Nodes
The deep (cervical) lymph nodes receive all of the lymph from the head and neck – either directly or indirectly via the superficial lymph nodes. They are organised into a vertical chain, located within close proximity to the internal jugular vein within the carotid sheath. The efferent vessels from the deep cervical lymph nodes converge to form the jugular lymphatic trunks.
The nodes can be divided into superior and inferior deep cervical lymph nodes. They are numerous in number, but include the prelaryngeal, pretracheal, paratracheal, retropharyngeal, infrahyoid, jugulodigastric (tonsilar), jugulo-omohyoid and supraclavicular nodes.