What are the major blood and nerve supplies to the tongue?

Major Blood Supply and Nerve Supply to the Tongue

The tongue receives its primary blood supply from the lingual artery, a branch of the external carotid artery, while its primary motor innervation comes from the hypoglossal nerve (cranial nerve XII), which provides somatic motor innervation to the intrinsic and extrinsic muscles of the tongue.

Blood Supply of the Tongue

• The lingual artery, a branch of the external carotid artery, is the main blood supply to the tongue, with an average length of approximately 9.73 cm 1
• The lingual artery runs in an inferolateral position at the tongue base, approximately 2 cm inferior and 1.11 cm lateral to the foramen cecum 1
• Within the tongue, the lingual artery forms a rich vascular network, with more abundant capillary circulation in the lingual papillae containing taste buds 2
• The blood vessels of the tongue receive autonomic innervation from:
  • Adrenergic sympathetic vasoconstrictor fibers
  • Cholinergic parasympathetic vasodilator fibers 2

Nerve Supply of the Tongue

Hypoglossal Nerve (CN XII)

• The hypoglossal nerve is the primary motor nerve of the tongue 3, 4
• Origin: The hypoglossal nerve nucleus arises in the dorsal medulla 3
• Course:
  • The hypoglossal rootlets traverse the premedullary cistern dorsal to the vertebral artery 3
  • The nerve enters the hypoglossal canal where it is surrounded by a venous plexus 3
  • The extracranial hypoglossal nerve travels caudally within the carotid space 3
  • It then courses anteriorly inferior to the hyoid 3
• Function: Provides somatic motor innervation to:
  • The intrinsic muscles of the tongue
  • The extrinsic muscles of the tongue (except the palatoglossus muscle)
  • The infrahyoid strap muscles via the ansa cervicalis 3

Neurovascular Bundle Positioning

• The hypoglossal nerve/lingual artery neurovascular bundle (HLNVB) is positioned:
  • 2.7 cm inferior and 1.6 cm lateral to the foramen cecum
  • 0.9 cm superior to the hyoid bone
  • 2.2 cm medial to the mandible 5
• This inferolateral location allows for aggressive tongue base resection without neurovascular compromise 5

Clinical Significance

• Hypoglossal nerve palsy presents with:
  • Dysarthria
  • Deviation of the tongue to the side of the lesion upon protrusion 3
• Common causes of hypoglossal nerve palsy include:
  • Neoplasms (most common cause, especially involving the hypoglossal canal)
  • Brainstem infarct
  • Demyelinating disease
  • Vascular lesions
  • Trauma
  • Inflammatory processes
  • Infectious processes 3
• The blood supply to the hypoglossal nerve itself comes from multiple sources:
  • Ascending pharyngeal artery as it exits the hypoglossal canal
  • Occipital artery
  • Direct branches from the external carotid artery
  • Branches from the lingual artery within and close to the tongue 6
• Damage to these vessels may account for hypoglossal palsy after carotid endarterectomy through mechanisms such as ischemia, thermal injury, or intraneural hematoma 6