gross anatomy week 2 face and scalp

cranial bones #

8

facial bones #

14

three branches of trigeminal nerve

ophthalmic, maxillary, and mandibular

CN V1

supra-orbital, supratrochlear, lacrimal, infratrochlear, and external nasal

CN V2

zygomaticotemporal, infra-orbital, zygomaticofacial

CN V3

auricotemporal, mental, and buccal

trigeminal nerve role

cutaneous sensation to the face and motor innervation of muscles of mastication

facial nerve function

motor innervation to muscles facial expression

facial nerve branches

five terminal branches that provide innervation to muscles of facial expression (temporal, zygomatic, buccal, mandibular, and cervical)

posterior auricular nerve does

not go through parotid gland

herpes zoster ophthalmicus

shingles viral infection of CN V1

shingles viral infection of CN V1

results in vesicles erupting secondary to a viral infection; can damage the cornea and impact vision

trigeminal neuralgia

tic douloureux, sudden and intense pain, most common in V2 territory

trigeminal nerve lesion

ipsilateral to side of injury, sensory loss of the face (except for angle of mandible), cornea, conjunctiva, mucous membrane; paralysis of muscles of mastication

bells palsy

facial nerve paralysis; idiopathic, viral infection, or trauma

results of bells palsy

paralysis of muscles of facial expression, dropping eyelid and mouth, inability to completely close the eye, corneal ulceration, weakened lips (resulting in speech deficits)

external carotid artery travels

superiorly as the facial artery branches off

facial artery continues superiorly as

superior and inferior labial arteries branch off

facial artery terminates as

angular artery

external carotid eventually terminates as

superficial temporal artery

temporal arteritis

swelling of blood vessels with headache, jaw pain, vision loss, and fatigue. requires biopsy for diagnosis

application of facial artery

palpate on inferior border of mandible due to thin tissue

internal carotid artery branches

supraorbital and supratrochlear

facial vein and retromandibular vein join to drain into

internal jugular vein

superficial temporal vein and the maxillary vein form

retromandibular vein (posterior branch)

which veins drain into facial vein

angular vein, superior labial, inferior labial veins, and cavernous sinus

retromandibular vein joins the posterior auricular vein to form

external jugular vein

scalp layers (superficial to deep)

skin, connective tissue, aponeurosis, loose connective tissue layer, periosteum

innervation of scalp

trigeminal nerve (V1, V2, and V3) and ventral rami of C2 and dorsal rami of C2

connective tissue: anastomosis in layer two leads to

significant bleeding

lacerations deep to layer three of scalp result in

gaping due to pull of occipitofrontalis

blood supply of scalp

supratrochlear, supraorbital, superficial temporal, posterior auricular, and occipital

emissary veins

pass through foramina in the calvaria and connect the veins of the scalp with the dural venous sinuses

emissary veins increase risk of

scalp infections as anything in layer four can spread into cranial cavity via the veins

quick management of a laceration can decrease

risk of infection and subsequent spreading

parotid gland aka

salivary gland

structures that pass through parotid gland

facial nervem retromandibular nerve, and external carotid artery

structures anterior to parotid gland

5 terminal branches of facial nerve

structures superior to parotid gland

CN V3 (the auriculotemporal nerve branch)

structures posterior to parotid gland

posterior auricular nerve, branch of facial nerve

mumps can be mistaken for

toothache

pain, infection or swelling (parotiditis) can occur secondary to

mumps; parotid sheath aggravating by great auricular nerve

buccal fat pad

superficial to buccinator; size changes depending on nutritional status; most prominent in infants

occipitofrontalis

elevates eyebrow as when surprised

orbicularis oculi

closes eye as in blinking

orbicularis oris

closes lips, protrudes lips as for kissing

buccinator

compresses cheeks; mastication, sucking, whistling

levator labii superioris

elevates lip

zygomaticus major and minor

elevates corner of mouth as when smiling

platysma

pulls down lower lip and mouth, results in a grimace

depressor angularis oris

frowning, pulls edges of lips down

nasalis

flares nostrils