Jugularis 1

• External carotid artery


  Originates from the bifurcation of the common carotid artery at the level of C4 vertebrae, within the carotid triangle of the neck
• External carotid artery


  Supplies most of the external skull, except for a small region between the two eyes which is supplied by the ophthalmic artery, a branch of the internal carotid artery
• Branches of the external carotid artery

  • Superior thyroid artery
  • Lingual artery
  • Facial artery
  • Ascending pharyngeal artery
  • Occipital artery
  • Posterior auricular artery
  • Superficial temporal artery
  • Maxillary artery
• Superior thyroid artery


  Descends to the thyroid gland
• Lingual artery


  1. Ascends to the tongue

  2. Has several additional branches, among them sublingual artery and deep lingual artery
• Facial artery


  1. Ascends across the face and towards the orbit

  2. Has several additional branches: Ascending palatine artery, Tonsillar artery, Glandular artery, Submental artery, Inferior labial artery, Superior labial artery, Angular artery
• Ascending pharyngeal artery


  1. Supplies the pharynx, middle ear and the dura mater

  2. Gives off the posterior meningeal artery
• Occipital artery


  Supplies the occiput, meaning the back of the head
• Posterior auricular artery


  Supplies the mastoid air cells, parotid gland and the middle ear
• Superficial temporal artery


  1. Supplies the temple, vertex and forehead

  2. Vertically running

  3. Gives off transverse facial, a frontal and a parietal branch
• Maxillary artery


  1. Passes through the infratemporal fossa and the pterygopalatine fossa

  2. Supplies masticatory muscles, dura mater, mandible, lower teeth, maxilla, upper teeth, middle ear, nasopharyx, palate and deep facial layers

  3. Has many additional branches: Middle meningeal artery, Inferior alveolar artery, Buccal artery, Deep temporal arteries, Posterior superior alveolar artery, Infraorbital artery, Middle superior alveolar artery, Anterior superior alveolar artery, Sphenopalatine artery (terminal branch), Descending palatine artery (terminal branch)
• Right subclavian artery


  Arises from the brachiocephalic trunk
• Left subclavian artery


  Arises as a direct branch of the Aortic arch
• Parts of the subclavian artery

  • Thoracic part (deepest)
  • Muscular part
  • Cervical part (most superficial)
• Branches of the subclavian artery

  • Vertebral artery
  • Internal thoracic artery
  • Thyrocervical trunk
  • Costocervical trunk
  • Transverse cervical artery
  • Dorsal scapular artery
• Vertebral artery


  • Ascends, reaching the vertebral column at the transverse foramen of the 6th/7th cervical vertebrae
  • Supplies part of the brain
• Internal thoracic artery


  • Descends behind sternum/costal cage
  • Supplies the thorax and diaphragm
  • Has several minor branches: Supplying the thymus, trachea, sternum and mediastinum, Pericardiacophrenic artery, Intercostal branches, Musculophrenic artery, Superior epigastric artery
• Thyrocervical trunk


  • Ascends
  • Passes close to the medial margin of the anterior scalenus muscle
  • Has 4 branches: Inferior thyroid artery, Ascending cervical artery, Superficial cervical artery, Suprascapular artery
• Costocervical trunk


  • Has two branches: Supreme intercostal artery, Deep cervical artery
• Scalenotracheal fossa


  • Deep fossa in supraclavicular region
  • Between the anterior scalenus muscle and the trachea
• Structures in the scalenotracheal fossa

  • Carotid sheath
  • Internal jugular vein(lateral)
  • Vagus nerve (Inbetween and behind)
  • Common carotid artery (medial)
  • Subclavian artery
  • Vertebral artery
  • Internal thoracic artery
  • Thyrocervical trunk
  • Recurrent laryngeal nerve
  • Sympathetic trunk(Behind the carotid sheath)
  • Middle cervical ganglion
  • Paratracheal lymph nodes
  • Parajugular lymph nodes
  • Deep ansa cervicalis(In front of the carotid sheath)
• Superficial veins of the head and neck

  Internal jugular vein, External jugular vein, Anterior jugular vein
• Internal jugular vein


  • Drains blood from the interior of the skull, including the brain
  • Descends from the jugular foramen to its union with the subclavian vein, to form the brachiocepahlic vein
  • Embedded within the carotid sheath
• External jugular vein


  • Drains blood from the occipital vein and nuchal region
  • Much smaller compare to the internal jugular vein
  • Drain to the subclavian vein
  • Reside within the superficial cervical fascia
• Anterior jugular vein


  • Drains blood from the superficial anterior neck region
  • The smallest vein of the three
  • Makes an anastomoses between the two other jugular veins, called the jugular venous arch
  • Reside within the superficial cervical fascia
• Superficial veins and deep veins

  The superficial veins are most closely related to the deep veins in the area of the Angular vein, with an associated risk of spreading infections intracranially
• External and internal jugular veins

  Communicate by valvless anastomoses, allowing blood to drain from the external jugular vein and back into the internal jugular vein. This is clinically significant, as it provides a route by which bacteria from the skin of the head may get access to the meninges.
• Pterygoid venous plexus


  • Venous network situated behind the mandibular ramus, between the muscles of mastication
  • Extensive connection with adjacent veins such as deep facial vein, deep temporal veins and maxillary vein
• Emissary veins


  • Connection between the superficial cranial veins and the dural sinuses
  • Condylar, Mastoid, Occipital and Parietal emissary veins
  • Venous anastomoses as portals of infections - Very clinically important as deep spread of bacterial infections from the facial region may result in cavernous sinus thrombosis (Infection leading to clot formation that may occlude the sinus)
• Parapharyngeal space


  • Only the pharyngeal wall separates this space from the palatine tonsils - May therefore damage the internal carotid artery during surgery
  • Infections that reach the parapharyngeal space may travel with the internal carotid artery, and cause meningitis or with the internal jugular vein, and cause thrombosis
• Retropharyngeal space


  • Continuous with the posterior mediastum
  • Infections can spread and cause mediastinitis
• Trigeminal nerve (CN V)


  • Largest cranial nerve
  • Has three main branches: Ophthalmic nerve (V1), Maxillary nerve (V2), and Mandibular nerve (V3)
• Ophthalmic nerve (CN V1)


  • Provides somatosensory innervation of the skin of the forehead, upper eyelids, nasal dorum, the orbit and its content, and part of the dura mater, mucosa in the nasal cavities and the paranasal sinuses
  • Passes through the superior orbital fissure
  • Has several branches: Lacrimal nerve, Frontal nerve, Supratrochlear nerve, Supraorbital nerve, Nasociliary nerve
• Maxillary nerve (CN V2)


  • Provides somatosensory innervation of the middle part of the face (lower eyelids, upper lip, alae of nose, and upper part of cheeks), upper teeth, and part of the nasal, oral and nasopharyngeal mucosa
  • Runs through the foramen rotundum, to reach the pterygopalatine fossa
  • Branches at the pterygopalatine ganglion
  • Has several branches: Zygomatic nerve, Infraorbital nerve
• Somatosensory innervation


  Innervation of the skin and other sensory structures
• Maxillary nerve


  1. Runs through the foramen rotundum

  2. Reaches the pterygopalatine fossa

  3. Branches at the pterygopalatine ganglion
• Branches of the maxillary nerve

  • Zygomatic nerve
  • Infraorbital nerve
  • Greater and lesser palatine nerves
• Zygomatic nerve


  • Reaches the orbit through the inferior orbital fissure
  • Runs on the inferior orbital wall
  • Has zygomatico-facial and zygomatico-temporal branches
• Infraorbital nerve


  • Enters the orbit through the inferior orbital fissure
  • Runs in the infraorbital groove
  • Enters the infraorbital canal
  • Exits through the infraorbital foramen
  • Branches to innervate the molar, premolar and incisor teeth, and the skin between the eye and mouth
• Mandibular nerve (CN V3)


  • Somatosensory innervation of the lower part of the face, teeth of the lower jaw, and part of the oral mucosa
  • Motor innervation of 8 muscles: 4 masticatory muscles, anterior belly of digastric, mylohyoid, tensor veli palatini, tensor tympani