EXAM 2 - Review of CN, CSF, Blood Supply & Facial Muscles...Participatory exercise 2

lateral ventricles of brain

ventricles found in each cerebral hemisphere

anterior horn of lateral ventricle

frontal lobe

inferior horn of lateral ventricle

temporal lobe

interventricular foramen brain

connects lateral ventricles to third ventricle

massa intermedia

A small, midline mass of gray matter that connects the right and left thalamic bodies

third ventricle

The midline ventricle that conducts cerebrospinal fluid from the lateral ventricles to the fourth ventricle.

cerebral aqueduct

connects the third and fourth ventricles

fourth ventricle

the ventricle located between the cerebellum and the dorsal pons, in the center of the metencephalon

lateral aperture of fourth ventricle

Holes in 4th ventricle that allows CSF to pass through

median aperture of fourth ventricle

An opening in the roof of the fourth ventricle that connects to the subarachnoid space

central canal of brain

- Hollow tube in spinal cord

- Continuous with ventricles

septum pellucidum

thin membrane that separates the anterior part of the lateral ventricles from each other.

choroid plexus

produces cerebrospinal fluid (CSF) within the ventricles

The flow of Cerebral Spinal Fluid (CSF) - starting in the lateral ventricle

i. Lateral ventricle

ii. Interventricular foramen (of Monro)

iii. Third ventricle

iv. Cerebral aqueduct

v. Fourth ventricle

vi. From the fourth ventricle, CSF can escape via the lateral apertures, medial aperture, or central canal.

2 articular surfaces of temporomandibular joint

2 articular surfaces and their hyaline cartilage:

superior: articular tubercle and mandibular fossa of squamous portion of temporal bone

inferior: head of condyle of mandible

other structures in TMJ

articular/joint capsule

articular disc

synovial membrane

fibrous capsule

3 ligaments

Articular Disc in TMJ

fibrocartilage that is more firmly attached/moves with the mandible

separates the synovial cavity into superior and inferior compartments

synovial membrane of TMJ

gradually wears away as we age

Lateral (TMJ) ligament

lateral thickening fibrous capsule

zygomatic process of temporal bone and the articular tubercle to the neck of the mandible

stylomandibular ligament

mandible to cranium; weak reinforcement of TMJ; styloid process of temporal bone to the angle of the mandible

sphenomandibular ligament

mandible to cranium; weak reinforcement of TMJ; spine of sphenoid bone to the lingula of the mandible

When the mouth opens (mandibular depression) what happens TMJ

the head of the mandible with the articular disc slides anteriorly until the head lies inferior to the articular tubercle. There is also rotation of the mandibular head on the inferior surface of the articular disc.

When the protrusion and retrusion of mandible, what happens TMJ

the heads of the mandible (with their articular discs) slide anteriorly (protrusion) and posteriorly (retrusion) on the articular surface of the temporal bone

Dislocation of TMJ

refers to the case where the heads of the mandible and their articular discs slide anteriorly past the articular tubercle of the temporal bone

Elevation of mandible/closing mouth TMJ muscles

temporalis

masseter

medial pterygoid muscles

mandibular protrusion TMJ muscles

lateral pterygoids aided by medial pterygoids

mandibular retrusion TMJ muscles

temporalis muscle (posterior fibers)

Trigeminal nerve V1

opthalmic

general sensory for the forehead

Trigeminal nerve V2

general sensory for the region below the eyes

trigeminal nerve V3

general sensory for the lower jaw and tongue and motor to the muscles of mastication

dermatomes

areas of the body supplied by sensory fibers associated with a particular dorsal nerve root of a spinal nerve

Regions of the face can be divided into ______ , however

dermatomes

it is not the spinal roots that provide sensory innervation for the majority of these regions, but the branches of the trigeminal nerve

The posterior regions of the head receive sensory input from

the dorsal rami of the cervical spinal nerves

-primarily C2 while the region between receives supply from C3 (branches from cervical plexus)

maxillary sinusitis

most common of all the sinuses to be infected, infection can spread from sinus to upper teeth...s/s of sinus infection plus tooth pain (because the V2 branch also innervates teeth via superior alveolar nerve)

Facial nerve

special motor to the muscles of facial expression and special sensory for taste from the anterior 2/3's of the tongue

5 main branches of facial nerve

Temporal

zygomatic

buccal

mandibular

cervical

clinical application of facial nerve

bell's palsey

main arteries of the head

supraoribtal arteries

infraorbital arteries

facial arteries (palpate pulse)

maxillary arteries

lingual arteries

superficial temporal arteries (palpate pulse)

occipital arteries

supraoribital arteries

infraorbital arteries

facial arteries

maxillary arteries

lingual arteries

superficial temporal artery

occipital arteries

Primary venous drainage for the face

facial vein and this vessel joins with the retromandibular vein and they both drain into internal jugular vein in neck

lymphatics superficial group

occipital

retroauricular (mastoid)

parotid

submandibular

superficial cervical

deep cervical

occipital node

retroauricular node

parotid node

submandibular node

superficial cervical node

deep cervical node

sublingual gland

submandibular gland

Parotid salivary gland

many structures are related to or pass through

located inferior and just anterior to each external auditory meatus and between each ramus of the mandible and each mastoid process of the occipital bone

important structures within the parotids

facial nerve and branches

retromandibular vein

external carotid artery

parotid lymph nodes (superficial; drain into superficial and deep cervical nodes)

Clinically important structures related to the parotids

CN V2 (auricotemporal nerve)

great auricular nerve (C2/C3)

glossopharyngeal nerve

Occipitofrontalis (frontal belly) action

innervation

Frontal belly covers forehead;

Elevates eyebrows & wrinkles forehead horizontally

EMOTION: Surprise, Curiosity

N: facial

Occipitofrontalis (occipital belly)

action and nerve

occipital belly covers posterior skull; moves scalp posteriorly

EMOTION: Surprise, Curiosity

N: facial

Occipitofrontalis: Epicranial aponeurosis

connects the frontal and occipital bellies

Temporoparietalis muscle

action and nerve

tightens scalp

N: facial nerve

emotion:

24

Orbicularis oculi muscle

action and nerve

Closes eyelids

EMOTION: Winking, blinking; squinting

N: facial nerve

Corrugator supercilii muscle action and innervation

Draw eyebrows inferomedially creating vertical wrinkles above the nose

EMOTION: Concern, skepticism

N: facial nerve

Nasalis muscle

action and innervation

transverse part: compresses nostrils

alar part: dilates nostrils

EMOTION: Flares nostrils, as with anger

N: facial nerve

Procerus action and innervation

Depresses medial eyebrow, transverse wrinkles over the nose

EMOTION:Dislike or distain

N: facial nerve

Zygomaticus major action and innervation

elevates angle of mouth

EMOTION: smile

N: facial nerve

Mentalis action and innervation

Elevates and protrudes lower lip

EMOTION: pouting

N: facial nerve

Depressor labii inferioris action and innervation

Depresses the lower lip

EMOTION: Frown

N: facial nerve

Depressor anguli oris action and innervation

depresses angle of mouth

EMOTION: frown

N: facial nerve

Risorius

pulls angle of mouth laterally

EMOTION: allows for smiling

N: facial nerve

Platysma

Tenses the skin of the neck, depresses mandible

expression: eek

N: facial nerve

Auricularis

ant: elevates and draws auricle forward

post: elevate and retract auricle

sup: retracts and elevates auricle

N: facial nerve

Orbicularis oris

compresses and protrudes lips

EMOTION: kissing, whistling

N: facial nerve

Buccinator

deep to the masseter; Compresses cheek; aid in mastication

EMOTION: Whistling, sucking

N: facial nerve

Levator labii superioris alequae nasi

(LLSAN)

Elevates the upper lip, dilates the nostrils

EMOTION: "elvis" snarl

N: facial nerve

Levator labii superioris

Elevates and everts upper lip

EMOTION: dilator of mouth look...teeth coming together

N: facial nerve

Zygomaticus minor

elevates upper lip

EMOTION: smile

N: facial nerve

Levator anguli oris

elevates angle of mouth

EMOTION: smiling

N: facial nerve

muscles of mastication

masseter

temporalis

medial pterygoid

lateral pterygoid

masseter

OIAN

Origin: zygomatic arch

Insertion: mandible

action: elevate, protract, and retract mandible

innervation: trigeminal, V3

temporalis OIAN

origin: temporal fossa

insertion: mandible

action: elevate and retract mandible

innervation: All trigeminal, V3

medial pterygoid OIAN

origin: pterygoid plate insertion: mandible action: elevate and protract mandible, and lateral movement of opposite side of mandible

innervation: All trigeminal, V3

lateral pterygoid OIAN

origin: pterygoid plate

insertion: mandible

action: depress and protract mandible, and lateral movement of opposite side of mandible

innervation: All trigeminal, V3

muscles of the tongue

genioglossus, styloglossal muscle, hyoglossal muscle, palato(chondro)glossal muscle

genioglossus action and innervation

action: depresses and protrudes tongueinnervation: CN XII (hypoglossal)

hyoglossal muscle action and innervation

depresses tongue innervation: CN XII (hypoglossal)

styloglossal muscle action and innervation

retrude and curls the tongue

innervation: CN XII (hypoglossal)

palato(chondro)glossal action and innervation

elevates posterior tongue to palateinnervation: CN X (Vagus)

CN I

Olfactory Nerve;

Sensory

Smell

extraocular muscles

inferior rectus

medial rectus

lateral rectus

superior rectus

superior oblique

inferior oblique

levator palpebrae superioris

inferior rectus action and innervation

depresses eye

III (oculomotor)

medial rectus action and innervation

moves eye medially (III oculomotor)

lateral rectus action and innervation

moves eye laterally (VI abducens)

superior rectus action and innervation

elevates eye;

III oculomotor

superior oblique action and innervation

Depresses eye and turns it laterally

CN IV (trochlear)

inferior oblique action and innervation

Elevates eye and turns it laterally

III (oculomotor)

levator palpebrae superioris action and innervation

action: elevates upper eyelid

innervation: III (oculomotor)

olfactory bulb

where the olfactory nerves synapse, on the inferior aspect of the frontal lobe

olfactory tract

originates in the olfactory bulb and runs caudally on the ventral aspect of the frontal lobe.