Anterior triangle of neck

Transcription

1 Anterior triangle of neck Dept. of Anatomy Zhou Hong Ying

2 Outline boundary and subdivisions of ant. triangle contents of the triangle Muscles: suprahyoid muscles, infrahyoid muscles Nerves: CNⅩ, CNⅪ, CNⅫ, sympathetic nerve, ansa cervicalis Arteries: common carotid a., ECA, ICA, subclavian a. & their branches Veins: internal jugular v., external jugular v., subclavian v. dissection of this area

3 Boundary of anterior triangle apex: jugular notch floor: the pharynx, larynx, and thyroid gland.

4 subdivisions Carotid triangle Muscular triangle Submandibular triangle Submental triangle

5 Muscles of anterior triangle SCM Hyoid muscles: suprahyoid group & infrahyoid group

6 Suprahyoid Muscles digastric stylohyoid mylohyoid geniohyoid hyoglossus

7 Infrahyoid muscles Superficial layer: sternohyoid medially & omohyoid laterally Deep layer: sternothyroid & thyrohyoid

8 Actions of the Suprahyoid & Infrahyoid Muscles

9 The Pharynx & Larynx

10 Subclavian artery Arteries of neck Common carotid artery(cca) Internal carotid artery (ICA) External carotid artery(eca)

11 common carotid artery

12 Carotid sinus Carotid body

13 Branches of ECA 1 branch arises medially (ascending pharyngeal) 2 branches arise posteriorly (occipital and posterior auricular) 3 branches arise anteriorly (superior thyroid, lingual, and facial).

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15 The Veins of the Neck Internal jugular vein External jugular vein Subclavian vein Note that external jugular vein is tributary of subclavian vein.

16 The Veins of the Neck

17 Nerves of Anterior Cervical Triangle glossopharyngeal nerve hypoglossal nerve vagus nerve Ansa Cervicalis sympathetic nerves Ansa Cervicalis

18 Ansa cervicalis superior root comes from C1 via CN XII. inferior root is derived from C2 & C3. supply infrahyoid muscles except thyrohyoid.

19 The Ansa Cervicalis

20 Cranial Nerves CN Ⅸ(Glossopharyngeal nerve ) CNⅩ (vagus) CNⅪ (accessory) CNⅫ (hypoglossal)

21 Accessory nerve Glossopharyngeal nerve: innervates the stylopharyngeus muscle, send a branch to the carotid sinus, and sensory branches to the pharynx

22 Superior Laryngeal Never Vagus nerve

23 Hypoglossal nerve

24 Cervical Sympathetic trunk

25 The Cranial Nerves of Neck

26 Relationships of vessels and nerves

27 The Carotid Sheath

28 Submandibular, submental Anterior and posterior belly of digastric m, inferior border of mandible bone. R & L Anterior bellies of digastric m and hyoid bone

29 Floor of the Mouth mylohyoid muscle hyoglossus muscle geniohyoid muscle

30 Floor of the Mouth

31 Structures of the Submandibular Triangle

32 Structures of the Submandibular Triangle submandibular gland facial artery & vein lymph nodes hypoglossal nerve lingual nerve lingual artery

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34 Dissect the vessels & nerves in the carotid

35 Superficial dissection of anterior cervical region

36 Cut the SCM at its middle point to expose: common carotid a, internal carotid a, external carotid a, and its branches nerves

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38 CAROTID TRIANGLE Identify superficial veins: facial v., retromendibular v., & anterior jugular v. Clean & free SCM, then cut it in its middle & reflect both parts superiorly & inferiorly respectivly Clean infrahyoid muscles: sternohyoid, omohyoid, sternothyroid, & thyrohyoid. Notice: don t free their lateral margins through where nerves enter muscles

39 Confirm boundaries of carotid triangle Find ansa cervicalis on or within carotid sheath. Trace its superior root to hypoglossal nerve & inferior root to cervical plexus, as well as its branches to all infrahyoid, except thyrohyoid Open carotid sheath to expose internal jugular vein (IJV). Note its tributaries & then detach them Pull IJV to expose common carotid artery (CCA), which has no branches till it ascends to level of C4 where it bifurcates into external & internal carotid artery (ECA & ICA)

40 Note wall of end of CCA or beginning of ICA bulges out to form carotid sinus Within carotid sheath find vagus nerve between CCA (ICA) & IJV Trace ECA upward to posterior belly of digastric & try to find it five branches in carotid triangle