Head and Neck Anatomy PDF

Vasculature of Head and Neck Carotid Arteries Carotid arteries come from right brachiocephalic trunk and aortic arch (left) Bifurcates at C4 by upper border of thyroid cartilage into: ○...

Vasculature of Head and Neck Carotid Arteries Carotid arteries come from right brachiocephalic trunk and aortic arch (left) Bifurcates at C4 by upper border of thyroid cartilage into: ○ External carotid arteries → head and neck ○ Internal carotid arteries → brain and CNS with vertebral arteries (from thyrocervical trunk) With exception of 1 branch: ophthalmic artery External Carotid Artery Don’t learn all the branches of the branches, but the important ones are: Facial artery: curves around inferior border of mandible Angular a. - medial corner of eye Superior/inferior labial a. - anastamose around lip Superficial temporal a. Transverse facial a. Maxillary a.: in infratemporal fossa → pterygopalatine fossa Before mandible: middle meningeal artery (through foramen spinosum, one associated with blow to pterion), inferior alveolar Under lateral pterygoid: supplies TMJ Some Attendings Like Freaking Out Potential Medical Students Pterygopalatine fossa: infra-orbital, greater palatine, pharyngeal, sphenopalatine, posterior superior alveolar Internal Carotid Artery Generally supplies CNS but one branch contributes to the face: Ophthalmic artery Enters orbit with optic n. Via optic canal Branches into: ○ Lacrimal branch → Zygomatic bone Zygomaticofacial a. Zygomaticotemporal a. ○ Dorsal nasal a. ○ Supraorbital and supratrochlear a. → scalp ○ Anterior/posterior ethmoidal a. → nasal cavity  Venous Drainage Eventually all drains into subclavian vein External Jugular Vein (posteriorly) ○ Retromandibular vein (from maxillary and superficial temporal v.) ○ Posterior auricular vein Internal Jugular vein (anteriorly) ○ Facial vein Intracranial venous connections Facial vein communicates with superior ophthalmic vein (which leads to cavernous sinus) *** CAVERNOUS SINUS THROMBOSIS** Emissary veins from pterygoid plexus Facial and cranial veins are valveless - therefore infection risk Lymphatics ½ of the lymph nodes in the body lie in the head and neck The closer the structure is to the midline, the more likely it is to have bilateral lymphatic drainage Cancer = enlarged and hard, infection = enlarged and tender Lymphatic Drainage Submental - chin Submandibular - middle of face Pre-auricular/parotid - eyes, nose, lateral cheek → All end up draining into the deep cervical group Virchow’s Node (Supraclavicular node) = drainage of intra-abdominal/thoracic organs Jugulodigastric lymph node (upper cervical) = tonsil (sore throat, often permanently enlarged in children) Temporal Arteritis Definition Inflammation of temporal arteries RF/ Cause unknown Aetiology Female Old Frequently associated with polymyalgia rheumatica (PMR) - pain and stiffness in proximal joints Sx Throbbing headache and tenderness in temples (combing hair) Jaw pain (may be with chewing - claudication) Fevers and night sweats Unintentional weight loss Optic nerve ischaemia → double vision, sudden/permanent loss of vision in one eye Dx Physical examination: prominent temporal arteries, tenderness over temporal area, decreased pulses throughout body Blood tests: High ESR - inflammation C reactive protein - inflammation Increase in platelets Biopsy of artery (gold standard) Tx High dose corticosteroids (reduce inflammation)