Lymph node levels of the neck
The lymph nodes in the neck have historically been divided into at least six anatomic neck lymph node levels for the purpose of head and neck cancer staging and therapy planning. Differing definitions exist across specialties 1-4. The following is a synthesis of radiologically useful boundaries for each level.
Level I: submental and submandibular
- superiorly: mylohyoid muscle and mandible
- inferiorly: inferior border of the hyoid bone
- anteriorly: platysma muscle
- posteriorly: posterior border of the submandibular gland
There are two sublevels:
- level Ia (submental nodes): anteromedial between the anterior bellies of both digastric muscles
- level Ib (submandibular nodes): posterolateral to the anterior belly of the digastric muscles
Level II: upper internal jugular (deep cervical) chain
- superiorly: base of the skull at the jugular fossa
- inferiorly: inferior border of the hyoid bone
- anteriorly: posterior border of the submandibular gland
- posterolaterally: posterior border of the sternocleidomastoid muscle
- medially: medial border of the internal carotid artery
There are two sublevels:
- level IIa: inseparable from or anterior to the posterior edge of the internal jugular vein; includes jugulodigastric nodal group
- level IIb: posterior to and separable by a fat plane from the internal jugular vein
Level III: middle internal jugular (deep cervical) chain
- superiorly: inferior border of the hyoid bone
- inferiorly: inferior border of the cricoid cartilage
- anteriorly: anterior border of the sternocleidomastoid muscle
- posterolaterally: posterior border of the sternocleidomastoid muscle
- medially: medial border of the common carotid artery
Level IV: lower internal jugular (deep cervical) chain
- superiorly: inferior border of the cricoid cartilage
- inferiorly: level of the clavicle
- anteriorly: anterior border of the sternocleidomastoid muscle
- posterolaterally: oblique line drawn through the posterolateral edge of the sternocleidomastoid muscle and the lateral edge of the anterior scalene muscle 2
- medially: medial border of the common carotid artery
- includes medial supraclavicular nodes including Virchow node 1
Level V: posterior triangle
- superiorly: skull base at the apex of the convergence of sternocleidomastoid and trapezius muscles
- inferiorly: level of the clavicle
- anteromedially: posterior border of the sternocleidomastoid muscle
- posterolaterally: anterior border of the trapezius muscle
There are two sublevels:
- level Va: superior half, superior to inferior border of the cricoid cartilage (posterior to levels II and III); includes spinal accessory nodes
- level Vb: inferior half, inferior to inferior border of the cricoid cartilage (posterior to level IV); includes lateral supraclavicular nodes 1
Level VI: central (anterior) compartment
- superiorly: inferior border of hyoid bone
- inferiorly: superior border of manubrium (suprasternal notch)
- anteriorly: platysma muscle 8
- posteriorly: trachea (medially) and prevertebral space (laterally) 8
- laterally: medial borders of both common carotid arteries (medial to levels III and IV)
- includes anterior jugular, pretracheal, paratracheal, prelaryngeal/precricoid (Delphian), and perithyroidal nodes
Variant anatomic boundaries
Minor variations to the above anatomic boundaries have been described.
For example, head and neck surgeons may use different intraoperative landmarks 1,4:
- levels IIa and IIb are separated by the vertical plane defined by the spinal accessory nerve
- the medial border of levels III and IV and lateral border of level VI is defined by the lateral border of the sternohyoid muscle
- the posterior border of levels II through IV and anterior border of level V may also be defined by the plane of sensory branches of the cervical plexus
In addition, radiologists may describe supraclavicular nodes separately from levels IV and V using the transverse level of the clavicle as the border 9.
Additional neck levels
The above classification is not inclusive of several important nodal groups in the head and neck:
- superior mediastinal nodes
- retropharyngeal nodes
- parotid nodes
- occipital nodes
- posterior auricular (mastoid) nodes
- facial nodes
Other classification systems include some of these regions, but a consensus approach has not been reached. For example, with respect to "level VII," radiologists may apply this label to superior mediastinal nodes 2, radiation oncologists may apply this label to "prevertebral nodes" 3, and head and neck surgeons omit this level from their nomenclature altogether 1. Thus, it is best to name lymph node groups outside of the established levels I-VI. If "level VII" is used for superior mediastinal lymph nodes, it should refer to the extension of the paratracheal chain below the suprasternal notch but above the level of the brachiocephalic artery 4.
See also
Related Radiopaedia articles
Anatomy: Head and neck
- skeleton of the head and neck
-
cranial vault
- scalp (mnemonic)
- fontanelle
-
sutures
- calvarial
- facial
- frontozygomatic suture
- frontomaxillary suture
- frontolacrimal suture
- frontonasal suture
- temporozygomatic suture
- zygomaticomaxillary suture
- parietotemporal suture (parietomastoid suture)
- occipitotemporal suture (occipitomastoid suture)
- sphenofrontal suture
- sphenozygomatic suture
- spheno-occipital suture (not a true suture)
- lacrimomaxillary suture
- nasomaxillary suture
- internasal suture
- basal/internal
- skull landmarks
- frontal bone
- temporal bone
- parietal bone
- occipital bone
- skull base (foramina)
-
facial bones
- midline single bones
- paired bilateral bones
- cervical spine
- hyoid bone
- laryngeal cartilages
-
cranial vault
- muscles of the head and neck
- muscles of the tongue (mnemonic)
- muscles of mastication
-
muscles of facial expression
- occipitalis muscle
- circumorbital and palpebral muscles
- nasal muscles
- buccolabial muscles
- elevators, retractors and evertors of the upper lip
- levator labii superioris alaeque nasalis muscle
- levator labii superioris muscle
- zygomaticus major muscle
- zygomaticus minor muscle
- malaris muscle
- levator anguli oris muscle
- risorius muscle
- depressors, retractors and evertors of the lower lip
- depressor labii inferioris muscle
- depressor anguli oris muscle
- mentalis muscle
- compound sphincter
- orbicularis oris muscle
- incisivus superior muscle
- incisivus inferior muscle
- muscle of mastication:
- elevators, retractors and evertors of the upper lip
- muscles of the middle ear
- orbital muscles
- muscles of the soft palate
- pharyngeal muscles
- suprahyoid muscles
- infrahyoid muscles
- intrinsic muscles of the larynx
- muscles of the neck
- accessory muscles of the neck
- deep cervical fascia
-
deep spaces of the neck
- anterior cervical space
- buccal space
- carotid space
- danger space
- deep cervical fascia
- infratemporal fossa
- masticator space
- parapharyngeal space
- stylomandibular tunnel
- parotid space
- pharyngeal (superficial) mucosal space
- perivertebral space
- posterior cervical space
- pterygopalatine fossa
- retropharyngeal space
- suprasternal space (of Burns)
- visceral space
- surgical triangles of the neck
- orbit
- ear
- paranasal sinuses
- nose
- oral cavity
- pharynx
- larynx
- viscera of the neck
- blood supply of the head and neck
-
arterial supply
-
common carotid artery
- carotid body
- carotid bifurcation
- subclavian artery
- variants
-
common carotid artery
- venous drainage
-
arterial supply
- innervation of the head and neck
-
cranial nerves
- olfactory nerve (CN I)
- optic nerve (CN II)
- oculomotor nerve (CN III)
- trochlear nerve (CN IV)
-
trigeminal nerve (CN V) (mnemonic)
- trigeminal ganglion
- ophthalmic division
- maxillary division
- mandibular division
- abducens nerve (CN VI)
- facial nerve (CN VII)
-
vestibulocochlear nerve (CN VIII)
- vestibular ganglion (Scarpa's ganglion)
- glossopharyngeal nerve (CN IX)
-
vagus nerve (CN X)
- superior laryngeal nerve
- recurrent laryngeal nerve (inferior laryngeal nerve)
- (spinal) accessory nerve (CN XI)
- hypoglossal nerve (CN XII)
- parasympathetic ganglia of the head and neck
- greater occipital nerve
- third occipital nerve
-
cervical plexus
- muscular branches
- longus capitis
- longus colli
- scalenes
- geniohyoid
- thyrohyoid
-
ansa cervicalis
- omohyoid (superior and inferior bellies separately)
- sternothyroid
- sternohyoid
- phrenic nerve
- contribution to the accessory nerve (CN XI)
- cutaneous branches
- muscular branches
- brachial plexus
- pharyngeal plexus
-
cranial nerves
- lymphatic drainage of the head and neck
- embryological development of the head and neck