Infra-auricular nodes

At a glance

English

Infra-auricular nodes

Latin (TA2)

Nodi infraauriculares

System

Lymphatic

Region

Head

Side

Paired, left and right

About the infra-auricular nodes

The infra-auricular nodes are a subgroup of the parotid lymph nodes, the collection of nodes that lie in and around the parotid salivary gland in front of and below the ear. As the name says, these sit beneath the auricle, close to the lower end of the parotid gland where it reaches down behind the angle of the mandible. They are usually small, numbering one to a few, and lie either just under the parotid fascia or partly within the edge of the gland.

Their neighbours include the pre-auricular nodes above, in front of the tragus, and the intraglandular nodes buried within the gland. The retromandibular vein and the cervical branch of the facial nerve leave the lower pole of the parotid nearby, and the upper end of the external jugular vein forms just below them. The sternocleidomastoid muscle lies behind and below.

These nodes receive lymph from the lobule and lower parts of the auricle, from the skin over the angle of the jaw and the lower cheek, and from the lower part of the parotid gland itself. Their outflow runs down to the superior deep cervical nodes along the internal jugular vein, partly by way of the superficial cervical nodes on the external jugular vein.

Clinically, a lump just below the ear lobe raises a familiar question: is it a lymph node or a swelling of the parotid gland? Infra-auricular nodes enlarge with infections of the ear, scalp and face, and in general viral illness. They can also hold metastases from skin cancers of the ear and face, which matters during surgery on the lower pole of the parotid, where branches of the facial nerve must be protected.

Course and drainage

Begins at

Afferent vessels from the lobule and lower auricle, the skin over the angle of the mandible and the lower part of the parotid gland.

Drains into

Efferent vessels drain to the superior deep cervical nodes, partly via the superficial lateral cervical nodes along the external jugular vein.

Drains

Filters lymph from the lower ear and the region around the jaw angle. Enlargement suggests infection or tumour of the ear, overlying skin or parotid, and must be told apart from a parotid swelling.