Page 322 - Clinical Anatomy

ECA5 7/18/06 6:51 PM Page 307

The lymph nodes of the neck 307

Fig. 219◊Scheme of the
lymph nodes of the head
and neck.

here the arrangements of the lymph nodes of the head and neck as a whole
(Fig. 219). These can be grouped into horizontal and vertically disposed
aggregates.
The horizontal nodes form a number of groups which encircle the junc-
tion of the head with the neck and which are named, according to their
position, the submental, submandibular, superficial parotid (or preauricular),
mastoid and suboccipital nodes. These nodes drain the superficial tissues of
the head and efferents then pass to the deep cervical nodes (although some
lymph vessels pass direct to the cervical nodes, bypassing the horizontal
nodes).
The vertical nodes drain the deep structures of the head and neck. The
most important is the deep cervical group, which extends along the internal
jugular vein from the base of the skull to the root of the neck (Fig. 198). The
lymph then passes via the jugular trunk to the thoracic duct or the right
lymphatic duct.
The superficial cervical nodes lie along the external jugular vein, serve the
parotid and lower part of the ear and drain into the deep cervical group.
Along the front of the neck lies another group of vertically disposed
nodes, the infrahyoid (on the thyrohyoid membrane), the prelaryngeal and
the pre- and paratracheal nodes. These drain the thyroid, larynx, trachea and
part of the pharynx and empty into the deep cervical group.
The retropharyngeal nodes, lying vertically behind the pharynx, drain the
back of the nose, pharynx and Eustachian tube; their efferents pass to the
upper deep cervical nodes.
Thus all structures in the head and neck drain through the deep cervical
nodes either directly or ultimately.

Clinical features

1◊◊A constant lymph node lies at the junction of the internal jugular and
common facial veins—the jugulodigastric or tonsillar node. This becomes