Veinous Supply & Lymphatics of Head and Neck

What are the boundaries of the scalp? anterior, posterior and laterally

anterior: superior orbital margin

posterior: superior nuchal lines (occipital bones)

laterally: zygomatic arch on each side

What does each letter of scalp stand for?

skin, connective tissue, aponeurosis, loose areolar tissue (allows the aponeurosis to glide over the pericranium), pericranium

What is found in the skin layer?

hair, sebaceous glands and sweat glands

What may occur if there is any issues with the sebaceous glands? (2)

dandruff and skin dryness

What is found in the connective tissue layer of the scalp?

what is it?

what does it connect?

contains (2)

• close network of fibro-fatty tissue

• connects the overlying skin with the under lying aponeurosis

• contains large blood vessels and nerves

• the connective tissue is stretched

What can injury to a scalp cause?

bleeding (vessels can’t retract) and pain (when a haematoma forms)

What is the aponeurosis?

role?

the layer underneath?

acts as a tendon, connects the frontal belly and occipital belly of the occipito-frontalis muscle

tightly attached to the connective tissue

the loose subaponeurotic layer - loose areolar tissue

What is the pericranium?

the periosteum of the skull

continuous with endosteum at the sutures

What are the 3 cerebral meninges?

dura mater

arachnoid mater

pia mater

What is the dura mater?

what are the 2 layers?

its attachments?

dense inelastic membrane

meningeal - inner

endosteal - outer

loose contact with calvaria

strongly adherent to the base of the skull

What does the dura mater have?

reflections that are essentially fold of the dura mater,

What are the 4 folds of the dura amter

cerebral falx - lies between the 2 cerebral hemispheres

tentorium of cerebellum - separates the cerebellum from the cerebral hemispheres - roof of the cerebellum

tentorial incisure - for passage of the midbrains

cerebellar falx

diaphragma sellae - in contact with the pituitary gland - on the sella turcica

What is the cerebral falx shape and attachments?

sickle shaped

attached anteriorly to the crista galli of ethmoid,

posteriorly it blends into tentorium of the cerebellum

What is the cerebellar falx?

smaller

between cerebellar hemispheres along the posterior wall of the posterior cranial fossa

What is the role of the tentorium of the cerebellum?

forms the roof of posterior cranial fossa

What does the tentorial notch allow for?

opening for the brain stem

What is the diaphragma sella?

fold over the sella turcica

What are these sections?

What is this sinus called?

superior sagittal sinus

What are the other 2 sinuses?

what is the red arrow?

straight sinus

inferior sagittal sinus

confluence - where the superior sagittal connects with the straight sinus

What are these two sinuses?

sigmoid sinus - connects to the jugular foramen and drains venous blood into the jugular vein

transverse sinus

they are both connected to the confluence

What are these 2 sinuses?

where are they found?

cavernous sinus - in middle cranial fossa, on the side of the body of the sphenoid bone

superior and inferior petrosal sinuses - petrous part of the temporal bone

superior is more lateral on the image

the superior petrosal sinuses are connected to the transverse sinus

inferior petrosal sinus drains directly into the jugular vein through the jugular foramen

What structures are found in the cavernous sinus?

internal carotid artery and abducent nerve (C6) - run through the sinus

oculomotor (C3), trochlear (C4)and ophthalmic and maxillary divisions of trigeminal (C5) nerve lie in the lateral walls of the sinus

orange - pituitary gland

How is the flow of the blood in the Dural sinuses (Flow chart)

The venous drainage from the head and neck and brain terminates where?

internal jugular vein

the internal jugular vein drains where?

superior vena cava

what is the course of the internal jugular vein? (4)

emerges from the jugular foramen

passes through the carotid sheath

joins the subclavian vein to form the brachiocephalic vein

drain into the superior vena cava - the largest vein in the body

Name 4 other veins in the head and neck?

facial, pterygoid plexus. retromandibular vein, maxillary vein

Describe the facial vein

supraorbital and supratrochlear veins join it

communicates with the cavernous sinus through the ophthalmic vein via the supraorbital fissures

as it descends, it joins the deep facial vein (brings deoxygenated blood from the pterygoid plexus), pterygoid plexus and retromandibular vein

What i this image showing?

pterygoid plexus

PP drains into the deep facial vein join the facial vein

facial vein joins the retromandibular vein

all join the common facial vein

this will then join the internal jugular vein

Describe the retromandibular vein

formed by?

passes through

two divisions of exit?

formed by superficial temporal vein and maxillary vein

passes through the parotid gland

anterior - join the facial vein

posterior it joins the posterior auricular vein

Describe the maxillary vein

what can drain into it?

what does it pass between?

what does it join with

pterygoid plexus can drain into the maxillary veins

sphenomandibular ligament and the neck of the mandible

joins the superficial temporal vein

joins with the superficial temporal vein - forms the retromandibular veins

Give an example of a vein that also drains into the internal jugular vein?

lingual vein - drains the floor of the mouth and tongue

How is lymph formed and what is it composed of?

fluid within the blood is - plasma

plasma is filtered through blood capillaries into tissue space - interstitial fluid

interstitial fluid passes into the lymph vessels - lymph

lymph is composed of interstitial fluid and lymphocytes

What are the 3 functions of the lymphatic system?

1) draining excess interstitial fluid

2) carrying out immune response

3) transporting dietary lipids and lipid soluble vitamins such as A D E K

What are regional groups of lymph nodes? 5 regions

2, 2, 2, 2, 3

What do all of those lymph noes drain into?

drain into the deep cervical lymph nodes, which then enter the jugular vein

describe ethe occipital lymph nodes?

location

over the occipital bone - apex of the occipital protuberance

afferent vessels - back of the scalp (take in lymph)

efferent vessels - release lymph into the deep cervical lymph nodes

The other name for the mastoid lymph nodes?

location

retroauricular

over the lateral surface of the mastoid process

afferent vessel:

scalp above the auricle

posterior medial auricle

posterior wall of the external auditory meatus

efferent vessel:

deep cervical lymph nodes

auricle - ear

Describe the parotid lymph nodes

location?

on or in the parotid gland

afferent vessels:

• scalp above the parotid

• lateral surface of the auricle

• anterior wall of the EAM

• lateral eyelids

• middle ear

efferent:

DCLN

describe the buccal lymph nodes

location

found over the buccinator muscle, close to the facial vein

afferent vessels:

anterior scalp and forehead

anterior part of the face sides of the nose

efferent:

submandibular lymph nodes

Describe the submandibular lymph nodes

location

superficial to submandibular salivary glands

afferent:

• buccal lymph nodes

• upper lip

• lateral lower lip

• frontal, max, ethmoidal, air sinuses

• upper and lower teeth except the posterior teeth

• gingiva, except for the posterior gingiva

efferent:

• floor of the mouth

What are the efferent and afferent drainage of submental lymph nodes?

afferent vessels:

• tip of the tongue

• lower incisors and associated gum

• central lower lip

Efferent:

• submandibular ln

Describe the anterior CLN

location

along the course of anterior jugular vein

afferent - anterior neck

efferent : DCLN

Describe the superficial cervical lymph nodes

afferent and efferent?

afferent vessels:

angle of the mandible

lobule of auricle

efferent lymph nodes:

DCLN

What are the DCLN?

location

efferent

afferent

a chain of lymph nodes located along the course of the internal jugular vein mainly on its lateral aspect

extends from the base of the skull to the root of the neck

inside the carotid sheath

afferent - receives lymph from all lymphatic structures in the head and neck

efferent - join to form the jugular lymph trunk

What does the jugular lymph trunk join to?

right lymphatic duct or thoracic duct

venous system (vena cava)

where are the retropharyngeal lymph nodes in thi image?

name the lymph nodes