The lymph nodes draining the head and neck are classified into superficial and deep nodes.
Superficial lymphatics follow superficial veins while deep lymphatics follow arteries.
I. Superficial Nodes:
Drain superficial tissues of head and neck.
A. Circular Group:
Arranged in the form of a circle round the neck called “Pericervical collar”.
(a) Submental Nodes:
Lie in submental triangle.
(b) Submandibular Lymph Nodes:
On the inferior surface of submandibular gland.
(c) Pre-Auricular Nodes:
Lie infront of auricle.
(d) Post Auricular or Mastoid Nodes:
Lie behind auricle on surface of mastoid process.
(e) Occipital Nodes:
Lie in occipital region.
B. Vertical Group of Superficial Nodes:
1. Facial nodes – along facial vein.
2. Anterior cervical nodes – along anterior jugular vein.
3. Superficial cervical nodes – along external jugular vein.
4. Infrahyoid nodes – lie on thyrohyoid membrane, drains the larynx above the level of vocal cords.
5. Pre laryngeal nodes – lie on cricothyroid membrane drains larynx below the level of vocal cords.
6. Pretracheal nodes – lie on trachea close to inferior thyroid vein.
From all superficial nodes go to deep cervical nodes.
II. Deep Cervical Nodes:
They drain deeper tissues of head and neck, and are vertically disposed around the carotid sheath from the base of skull to the root of neck.
They are divided into superior and an inferior group by omohyoid muscle.
1. Superior Deep Cervical Nodes:
They drain cranial cavity, infratemporal fossa, parotid and submandibular nodes, root of the tongue, upper lateral part of thyroid gland, larynx and lower part of pharynx. Efferent passes to inferior deep cervical nodes.
(a) Jugulo Digastric Node:
Lies below the posterior belly of digastric muscle, where it crosses the internal jugular vein. It is the chief node draining the palatine tonsil, also called as tonsillar node.
(b) Inframastoid Node:
Lies below the tip of mastoid process drains pharyngeal tonsil are known as adenoid nodes.
2. Inferior Deep Cervical Nodes:
Lie below the level of thyroid cartilage and drain upper deep cervical nodes, lower part of thyroid gland, lower part of larynx, trachea and cervical part of oesophagus.
(a) Jugulo Omohyoid Node:
Lies above the inferior belly of omohyoid where it crosses the internal jugular vein. It drains the tongue and so also called as lingual node.
(b) Supraclavicular Nodes:
Lies in posterior triangle of neck above the clavicle. Accessory nerve is surrounded by these nodes.
(c) Para Tracheal Nodes:
Lie between trachea and oesophagus close to recurrent laryngeal nerve. They receive lymph from thyroid gland, oesophagus trachea and neighbouring areas.
(d) Retropharyngeal Nodes:
Lie in front of lateral mass of atlas along lateral border of longus colli, situated between buccopharyngeal fascia and the prevertebral fascia.
They drain – nasopharynx, soft palate, posterior part of hard palate, nose and auditory tube. Efferents reach to upper deep cervical nodes and then lower deep cervical nodes draining entire head and neck either directly or indirectly.
Efferents form jugular lymph trunk which on right side joins subclavian lymph trunk to form right lymph duct which joins the beginning of right brachiocephalic vein. On the left side jugular and subclavian lymph duct joins the thoracic duct which opens into the jugulo subclavian angle on left side.