1. Anatomy of neck + innervation of structures
Anatomy of neck + innervation of structures. Anatomy (gross and histological) and physiology of the lymphoid system, and of the head and neck –light, clinically relevant summary - DAN
From now I will pay more attention when we formulate FQs because this one sucked

2. Contents Neck Fascia Danger Triangle Larynx and Thyroid gland
Cervical lymphatic drainage

3. Fascia of the Neck
Structures in the neck are surrounded by a superficial fascia (subcutaneous tissue)
They are compartmentalised by layers of deep cervical fascia.

4. The Fascial layers Superficial cervical fascia Deep cervical fascia
Thin layer of CT that lies between the dermis of the skin and the investing layer of the deep cervical fascia
Cutaneous nerves, blood and lymph vessels, superficial lymph nodes, continous anterolaterally with the platysma
Deep cervical fascia
Investing layer, pretracheal layer, Prevertebral layer, Alar fascia and carotid sheath

5. Neck fascia SUPERFICIAL CERVICAL FASCIA Subcutaneous tissue
Investing layer
Pretracheal layer
Carotid sheath
Pre vertebral lyaer
DEEP CERVICAL FASCIA
Retropharyngeal space

6. Investing layer
Surrounds: Sternocleoidomastoids, Trapezius, submandibular gland, parotid gland
Superior attachments: Superior nuchal line, mastoid processes, zygomatic arches, inferior border of mandible, hyoid, spinous processes of cervical vertibrae

7. Pretracheal layer Includes Continuous with
Visceral part (thyroid gland, trachea, oesophagus)
Muscular part (infrahyoid muscles)
Continuous with
Carotid sheaths laterally
Buccopharyngeal fascia posterosuperiorly
Pericardium inferiorly

8. Carotid Sheath Extends from cranial base – root of neck Continuous
Anteriorly: investing and pretracheal layer
Posteriorly: Prevertebral layer
Important structures hidden within:
Common + internal carotid arteries
IJV
CN X
Deep cervical nodes
Carotid sinus nerve
Sympathetic nerve fibres

9. Pre Vertebral layer
Fixed to the cranial base superiorly, inferiorly fuses with the anterior longitudinal ligament
Forms a tubular sheath for the vertebral column and muscles surrounding it.

10. Retropharyngeal space
The largest interfascial space in the neck.
Potential space that consists of loose connective tissue between the prevertebral layer and the pretracheal layer.
The Alar fascia crosses the retropharyngeal space
Allows the movement of the pharynx, oesophagus, larynx and trachea
Major pathway for spread of infection

11. Neck fascia SUPERFICIAL CERVICAL FASCIA Subcutaneous tissue
Investing layer
Pretracheal layer
Carotid sheath
Pre vertebral lyaer
DEEP CERVICAL FASCIA
Retropharyngeal space

12. Importance of Fascia + its layers
Spread of infection is limited by facsial boundaries
Example
An Pus abscess posterior to the prevetebral layer may extend laterally in the neck and form a swelling posterior to the SCM. The pus may perforate the prevertebral layer and enter the retropharyngeal space, producing a bulge in the pharynx.
Dsyphagia, dysarthria

13. Danger triangle of the FACE
There is a communication between the facial vein and the cavernous sinus via the via the ophthalmic veins.
Bacterial infections can be caused by pus entering the brain's blood supply if pimples in the danger triangle are picked by dirty fingernails.

14. How???
Area of drainage of the facial vein

15. Larnyx

16. Larynx Innervation Blood supply Lymph drainage:
Motor: recurrent laryngeal nerves
S: superior laryngeal nerves
Blood supply
Superior half: superior laryngeal a. (branch of the s. Thyroid a.)
Inferior half: inferoir laryngeal artery (branch of the i. Thyroid artery)
Lymph drainage:
Superior + inferior deep cervical nodes  jugular trunk  thoracic duct (L)/right thoracic duct (R)
- Thyroid anatomy for those interested

17. PIE CHART

18. Thyroid Gland Innervation
Parasympathetic fibers come from the vagus nerves
Sympathetic fibers are distributed from the superior, middle, and inferior ganglia of the sympathetic trunk.
Blood supply
Superior half: superior thyroid artery
Inferior half: inferior Thyroid artery
Lymph drainage: periglandular nodes  prelaryngeal  pretracheal  paratracheal  mediastinal lymph nodes.
Thyroid gland

19. Thyroid gland Epithelium (principle cells) Colloid filled follicle
parafollicular cells

20. Anatomy of the Lymphoid system
Lymph nodes
Lymph Vessels
Main lymphatic vessels in the body
Right lymphatic duct
Thoracic duct
Cisterna Chyli

21. Lymphatic system/ Immune System

22. Lymph Node

23. Lymph node Histology

24. Important lymphatic sites

25. Waldeylers rings
Waldeyer's-Pirogov tonsillar ring  describes the lymphatic tissue in the pharynx and to the posterior oral cavity.
It contains
Pharyngeal tonsil (also known as 'adenoids' when infected)
Tubal tonsil (where Eustachian tube opens in the nasopharynx)
Palatine tonsils 
Lingual tonsils

27. Cervical lymph node drainage
Main lymph node groups in the neck
Submental/ Submandibular
Parotid
Retropharyngeal
Anterior cervical
Deep lateral cervical

28. Submental/Submandibular
1. Submental nodes
drainage from: adjacent skin, lips, floor of the mouth
drain to: the submandibular nodal group
2. Submandibular nodes
drainage from : anterior face, flow of the mouth, anterior oral cavity, and submental nodal group.
drain to :the high internal jugular chain (7)

29. Parotid 8. Parotid gland nodes Intra or extra glandular nodes.
drainage from: external artery canal, eustachian tube, adjacent skin, buccal mucosa.
drain to: high internal jugular chain (7)

30. Retropharyngeal Two compartments: Medial and lateral retropharyngeal.
Medial retropharyngeal
drainage from: nasal pharynx and oral pharynx
drain to: high internal jugular chain.
Lateral retropharyngeal: same as medial
Clinical sign: Early sign of nasal pharyngeal cancer may be presence of abnormal lateral retropharyngeal node in the patient over forty.

31. Deep Lateral cervical Consists of Internal Jugular chain (7)
drainage from: from parotid, retropharyngeal, and submandibular/submental groups.
drain to: the subclavian vein and/or internal jugular vein and/or into the right lymphatic duct and thoracic duct.
Posterior triangle
drainage from: occipital/mastoid, lateral neck, scalp, nasal pharyngeal sources.
drain to:
Supraclavicular: Same as Post. Triangle

32. Anterior cervical
Anterior jugular: superficial. Follows the course of the external jugular vein. Receives drainage from skin and muscles of the anterior neck. Drains to the thoracic duct.
Paraesophageal group: Tracheal esophageal groove nodes and delphian node. Abnormal delphian node is often an indicator subglottic laryngeal cancer extension.
This group receives drainages from hypopharynx, larynx, thyroid, and esophagus. Drainage is then to the thoracic duct.

33. Physiology of the lymphoid system
Re-uptake of excess fluid in interstitial tissue at capillary beds
Antigen presentation to naive lymphocytes
Activation of naive lymphocytes