Downloaded 906 times
Uploaded byMoamer Gabsa
Anterior triangle of the neck
The document discusses the anatomy of the anterior triangle of the neck. It begins by outlining the boundaries and contents of the anterior triangle. It then describes how the triangle is divided into four smaller triangles - the submental, submandibular, carotid, and muscular triangles - by the digastric and omohyoid muscles. Each smaller triangle's boundaries, floor, contents, and structures are defined in detail. Key structures discussed include the thyroid gland, carotid sheath, carotid sinus, and carotid body. Blood supply and lymphatic drainage of the thyroid gland are also summarized.
More Related Content
Similar to Anterior triangle of the neck
Anterior triangle of the neck
- 1. Moamer Gabsa ANTERIOR TRIANGLEOF THE NECK
- 2. ObjectivesObjectives By the endof this presentation you should know : Boundaries and contents of the anterior triangle of the neck Sub-divisions of anterior triangle and content of each one of these triangle
- 3. • An anteriorboundary: formed by the median line of the neck. • A posterior boundary: formed by the anterior border of the SCM. SCMSCM
- 4. • A superiorboundary: formed by the inferior border of the mandible. • An apex: located at the jugular notch in the manubrium.
- 5.
- 6. • A roof:formed by subcutaneous tissue containing the platysma. • A floor: formed by the pharynx, larynx, and thyroid gland.
- 7. • the digastricand omohyoid muscles divides the anterior triangle to small triangles . Omohyoid muscle Anterior belly of digastric posterior belly of digastric
- 8. The anterior cervicalregion is subdivided into four smaller triangles • The unpaired submental triangle and three small paired triangles: • submandibular • carotid •Muscular by the digastric and omohyoid muscles.
- 9.
- 10. • The submentaltriangle, inferior to the chin, is an unpaired suprahyoid area Hyoid bone Submental triangle Chin
- 11. • Inferiorly :body of the hyoid. • Laterally : right and left anterior bellies of the digastric muscles. • Floor: the two mylohyoid muscles. • The apex of the submental triangle is at the mandibular symphysis. • Base : is formed by the hyoid bone. Hyoid bone Submental triangle Anterior belly of digastric muscle Mylohyoid muscle 0 0 Mandibular symphysis
- 12. Anterior belly of digastricmuscle Mylohyoid muscle Anterior belly of digastric muscle
- 13. • Contents: submental lymphsubmentallymph nodesnodes and anterior jugularanterior jugular veinvein.
- 14.
- 15.
- 16. • It isan area between the inferior border of the mandible and the anterior and posterior bellies of the digastric muscle. • The floor is formed by the mylohyoid and hyoglossus muscles. Anterior belly of digastric posterior belly of digastric Sub mandibular triangle
- 17.
- 18. • The submandibulargland. • Submandibular lymph nodes. • The hypoglossal nerve (CN XII). • The nerve to the mylohyoid muscle (a branch of CN V3, which also supplies the anterior belly of the digastric). • Parts of the facial artery and vein, and the submental artery (a branch of the facial artery).
- 19. Submandibular lymph node Submandibular gland Facialvein Facial artery
- 20.
- 21.
- 22. • It isa vascular area bounded by the superior belly of the omohyoid, the posterior belly of the digastric, and the anterior border of the SCM. omohyoid SCMSCM Carotid triangle Posterior belly of digastric
- 23. • At thelevel of the superior border of the thyroid cartilage, the common carotid artery divides into the internal and external carotid arteries. Superior border of thyroid cartilage Thyroid cartilage Carotid sinus Common carotid artery Internal carotid artery External carotid
- 24. CONTENT OF CAROTIDTRIANGLE • The common carotid artery • The internal carotid artery • The internal jugular vein • The vagus nerve This structure covered by carotid sheath
- 25.
- 26. • The neurovascularstructures of the carotid triangle are surrounded by the carotid sheath and its contents. carotid sheath is a column of fascia that surrounds • The common carotid artery • The internal carotid artery • The internal jugular vein • The vagus nerve as these structures pass through the neck carotid sheath
- 27. CAROTID SINUS • Aslight dilation of the proximal part of the internal carotid artery, which may involve the common carotid artery. Carotid sinus
- 28. Innervated principally bythe glossopharyngeal nerve (CN IX) through the carotid sinus nerve, as well as by the vagus nerve (CN X). It is a baroreceptor (pressoreceptor) that reacts to changes in arterial blood pressure. Common carotid Carotid sinus Carotid sinus nerve Internal Carotid artery External Carotid artery
- 29. • A small,reddish brown ovoid mass of tissue that lies on the medial (deep) side of the bifurcation of the common carotid artery in close relation to the carotid sinus . • Supplied mainly by the carotid sinus nerve (CN IX) and by CN X. • It is a chemoreceptor that monitors the level of oxygen in the blood. It is stimulated by low levels of oxygen and initiates a reflex that increases the rate and depth of respiration, cardiac rate, and blood pressure. CAROTID BODY Carotid body
- 30. Jabl Mara –DarfurJabl Mara – Darfur
- 31.
- 32. •It is boundedby the superior belly of the omohyoid muscle, the anterior border of the SCM, and the median plane of the neck. Omohyoid muscle Muscular triangle Hyoid bone SCM SCM
- 33. CONTENT OF MUSCULARTRIANGLE • This triangle contains the infrahyoid muscles and viscera (e.g., the thyroid and parathyroid glands).
- 34. THYROID GLAND • Itis an Endocrine gland • lies deep to the sternothyroid and sternohyoid muscles, located anteriorly in the neck at the level of the C5 - T1 vertebrae • Butterfly in shape
- 35.
- 36. • It consistsof right and left lobes. • The isthmus unites the lobes over the trachea, usually anterior to the second and third tracheal rings. THYROID GLAND Right lobe Left lobe ist h m us
- 37. • Approximately 50%of thyroid glands have a pyramidal lobe. • This lobe, which varies in size, extends superiorly from the isthmus of the thyroid gland, usually to the left of the median plane pyramidal lobe
- 38. BloodBlood supplysupply ofofthyroidthyroid
- 39. • Superior andinferior thyroid arteries • The superior thyroid arteries descend from the external carotid arteries, it is accompanied by the external laryngeal nerve . • The inferior thyroid arteries, the largest branches of the thyrocervical trunks arising from the subclavian arteries. Superior thyroid inferior thyroid External carotid Thyrocevical trunk ArteriesArteries
- 40. • In approximately10% of people, a small, unpaired thyroid ima artery arises from the brachiocephalic trunk supply the isthmus Thyroid ima artery
- 41. VEINS • The superiorand middle thyroid veins drain into the IJVs • The inferior thyroid veins drain into the brachiocephalic veins Superior thyroid vein Middle thyroid vein Internal jugular vein Inferior thyroid vein Brachiocephalic vein
- 42. LYMPHATIC DRAINAGE • Thelymphatic vessels of the thyroid gland run in the interlobular connective tissue. • They communicate with a capsular network of lymphatic vessels. • They drain eventually to the superior and inferior deep cervical nodes
- 43. NERVE TO THYROIDGLAND • The nerves of the thyroid gland are derived from the superior, middle, and inferior cervical sympathetic ganglia. • These fibers are vasomotor, not secretomotor. They cause constriction of blood vessels. • Endocrine secretion from the thyroid gland is hormonally regulated by the pituitary gland.
- 44. REFERENCES • Moore, KeithL.; Dalley, Arthur F, Clinically Oriented Anatomy, 5th Ed. Lippincott Williams & Wilkins; 2006. • Richard L.Drake, Wayne Vogl,Adam W.M.Mitchell, GRAYS anatomy for students, Elsevier Inc. 2007