BMS 301 exam 3 head and neck-CSU

two subdivisions of the skull

neurocranium + viscerocranium

neurocranium

bones around the brain

viscerocranium

facial bones

cavities of the skull

cranial cavity

orbital cavity

nasal cavity

middle ear caity

air sinuses of the skull

paranasal sinuses- connected to nasal cavity

2 maxillary sinuses-next to nose

2 frontal sinuses - above eyes

2 sphenoid sinuses - base of brain

types of articulations found in the skull

non-moveable: sutures

synovial: temporal mandibular joint

fontanelles

soft spots on baby's skull where sutures are forming

name the 3 prominent sutures of the cranium

coronal

sagittal

lambdoid

describe the temporal mandibular joint

depress mandible-open

elevate - close

protract - forward

retract - backward

contains an articular disc

describe the three cranial fossae and a prominent bony landmark of each

base of the skull

anterior-houses frontal lobe- cribiform plate

middle- houses temporal lobes- sella turcica

posterior- houses cerebellum- foramen magnum

Define the pterion, bregma, and lambda.

pterion - frontal, parietal, temporal, & sphenoidal bone meet

bregma - coronal & sagittal sutures meet

lambda - sagittal & lambdoid sutures meet

Describe the thres major subdivisions of the brain

brainstem, cerebellum, cerebrum

cerebellum

Conscious perception: cognition, higher motor functions (blueprints), memory & learning, emotion, behavior, language

cerebellum (little brain)

controls ongoing movements, non-concious

Brainstem

medulla: vital reflexes; pons: vital reflexes; midbrain: auditory & visual reflexes

Give four characteristics, function and anatomy of the cerebrum.

contralateral perception/control - opposite side

somatotopy (body map) - correspondence of receptor location & location of processing in cerebrum (motor & sensory)

gyri & sulci - ridges & grooves (increase surface area)

basal nuclei (ganglia) - inner layer involved in movement

gyri

bumps of the cerebrum

sulci

grooves of the cerebrum

Describe the four lobes of the cerebrum, their position to each other and their function.

frontal - personality, reasoning, planning, motor outflow (primary cortex is precentral gyris)

parietal - primary somatosensory cortex = postcentral gyris

occipital - vision

temporal - memory & auditory

Describe the grey matter of the cerebrum, its location/function.

grey matter = neuronal cell bodies

cortex = outer layer

Describe the white matter of the cerebrum, its different fiber tracts and their destinations.

association fibers - connect lobe of single hemesphere

commiserol fibers - connect hemespheres (corpus colloseum)

projection fibers - go to and from the spinal cord

Define "functional localization".

Nerves that are together in certain parts of the body are also found together in the brain.

Name the branches off the aortic arch that give rise to the head's blood supply.

brachiocephalic trunk

subclavian arteries (upper limb)

common carotid arteries (head)

external carotid arteries (face)

internal carotid arteries (brain)

vertebral arteries (brain)

Give the distribution of and name and identify the primary branches of the external carotid artery which supply the face.

superior thyroid artery - thyroid gland, larynx, neck

lingual artery - tongue

facial artery

occipital artery - post. scalp & post. neck

maxillary branch - nasal/oral cavities, teeth, gums

inferior aveolar artery - teeth, gums

middle meningeal artery - dura mater

superficial temporal artery - scalp

Describe the functions of the cranial meninges.

compartmentalize the brain to reduce movement

venous sinuses won't collapse

Name and describe the individual layers of the meninges surrounding the brain; know how they differ from those of the spinal cord.

periosteal (outer) - stuck to skull

meningeal (inner) - infolds on itself

dura mater in spinal cord is one layer

Name the different dural infoldings and their associated venous sinuses.

falx cerebri (vertical) - superior sagittal, inferior sagittal, straight

falx cerebelli (vertical)

tentorium cerebelli (horizontal) - transverse

Describe the flow of venous blood from the brain; include descriptions of the major dural sinuses.

Sup. sagittal, inf. sagittal, and straight to confluens

confluens to transverse to sigmoid to internal jugular

covernous to sup. petrosal and inf. petrosal

sup. petrosal to transverse to sigmoid to internal jugular

inf. petrosal to internal jugular

What is unusual about the veins of the face and dural sinuses - are there any connections between the two?

no valves in the dural sinueses

facial nerves (VII) make connections with sinuses

Describe the two possible routes of arterial blood in the brain.

99% to brain tissue

1% to cerebral spinal fluid (CSF)

Describe the production of CSF, include a description of the choroid plexus.

arterial blood (choroidal artery)

choroid plexus (modified capillaries) in ventricles of brain filter the blood (energy dependent)

Describe the circulation of CSF, beginning with its production at the choroid plexuses and ending with its reabsorption into the blood.

choroid plexus > lateral ventricle > interventricular foramen > 3rd ventricle > cerebral aqueduct (aqueduct of the midbrain) > 4th ventricle > central canal of spinal cord

Describe hydrocephalus, its causes, include possible sites of blockage and accumulation of CSF.

Hydrocephalus - the buildup of CSF in the ventricles or cavities of the brain

causes - blocked CSF pathways

blockage sites - interventricular foramen, cerebral aqueduct (aqueduct of the midbrain), arachnoid granulations

accumulation - lateral ventricles, 3rd ventricle, subarachnoid space

Name the twelve pairs of cranial nerves and give a brief description of the function of each.

olfactory - smell

optic - vision

oculomotor - extra ocular muscles, pupil constriction, lens accomodation

trochlear - extra ocular muscles

trigeminal - skin on face, cornea, teeth, anterior 2/3 tongue, muscles of mastication

abducent - extra ocular muscles

facial - muscles of expression, ear canal, prart of auricle, taste (ant. 2/3 tongue, chorda tympani), lacrimal glands, submanidular & sublingual salivary glands

vestibulocochlear - hearing & balance

glossopharygeal - pharyngeal muscles, wall of pharynx, post 1/3 tongue, taste (post 1/3 tongue), parotid salivary gland

vagus - pharyngeal muscles, laryngeal muscles, ear canal, taste (base of tongue), thoracic & abdominal viscera

spinal accessory - trapezius muscle, sternoclediomastoid muscle

hypoglossal - muscles of tongue

Describe the differences between cranial nerves and spinal nerves.

CN - somatic (skeletal muscles), autonomic (parasympathetic only), special sense (ie. taste)

SN - somatic, autonomic, no special sense

Give the muscles of facial expression and describe their action.

frontalis - raise eyebrows

levator labii superioris - lift nose

zygomatic - smile

obicularis oculi - shut eyes (orbital/palpebral)

obicularis oris - kissing

depressor anguli oris - frown

What is unusual about the superficial fascia of the face, of the scalp?

face - loose & moves around

s = skin

c = connective tissue

a = epicranial aponeurosis

l = loose layer of connective tissue

p = periosteum

Describe the general sensory and motor functions of the facial nerve.

sensory - taste (ant. 2/3 tongue)

motor - muscles of expression

Describe the special sense function of the facial nerve.

chorda tympani - taste (ant. 2/3 tongue)

Identify the muscles of mastication and describe their action.

temporalis - closes & retracts

masseter - closes & protracts

med. pterygoid - closes & protracts

lat. pterygoid - opens & protracts

Describe the branches of the trigeminal nerve including any named nerves discussed in lecture and/or lab.

ophthalmic (V1) - eye, forehead & nose skin, cornea, meninges, frontal sinus, supraorbital nerve

maxillary (V2) - upper mouth, cheek skin, meninges, upper teeth, nasal cavity, throat, infraorbital nerve

mandibular (V3) - muscles of mastication, mandible skin, mucus membranes of mouth, TMJ, eardrum, lingual nerve, inferior alveolar nerve, mental nerve

Define the "pharynx".

Musculomembranous space posterior to oral cavity and nasal cavity (throat).

Define the boundaries and contents of the three subdivisions of the pharynx.

nasopharynx - base of skull to soft palate - nasal conchae, auditory tube opening, pharyngeal tonsils

oropharynx - soft palate to epiglottis - palatine tonsils, palatoglossal arch, palatophyrngeal arch

laryngopharynx - epiglottis to inferior aspect of larynx - vocal folds, vestibular folds

What muscles form the pharynx? What is their action, attachments and nerve supply?

Constrictor Muscles - pharyngeal plexus

superior constrictor - A: terigomandibular raphe

middle constrictor - A: hyoid bone

inferior constrictor - A: thyroid cartilage

What is the general motor and sensory supply to the pharynx?

motor: vagus (X)

sensory: glossopharyngeal (IX)

What are the "tonsils" and where are they located?

tonsils - lymph sturctures (immune system)

palatine tonsils - back of the oral cavity

pharyngeal tonsils - back of the nasal cavity

relationship between CN7 and CN5 (tongue)

CN7: taste and motor

CN5: sensory

What are the "arches" of the oropharynx and what actually forms them?

Formed by muscles.

palatoglossal arch

palatophyrngeal arch

What is a pattern generator?

Series of actions happen because of a single starting action (ie. swallowing)

What are the general "problems" associated with swallowing and how are they solved?

Problems:

trachea in line with oral cavity

do not want food in nasal cavity

Solutions:

suprahyoids pull trachea forward & spiglottis is forced down

palatopharyngeus, palati & lavator muscles elevate soft palate (X)

What muscles are involved in solving the problems associated with swallowing?

suprahyoids - pull trachea forward

palatopharyngeus - elevates soft palate

lavator palati - elevates soft palate

tensor palati - elevates soft palate

How is the auditory tube opened?

Tensor palati lifts the upper part of the opening.

Give the stages of swallowing.

1.) Tongue forces food back into oropharynx (voluntary)

2.) Food moves from oropharynx to laryngopharynx - breathing and chewing stop, sup & middle constrictors move food inferiorly, pharyngeal muscles contract so food cannot enter nasopharynx, pharynx is stabilized by stylopharyngeus muscle, hyoid and larynx elevated and brought forward so spiglottis is forced down over top of larynx by suprahyoids (involuntary)

3.) Food moved from laryngopharynx to esophagus by inferior contrictors (involuntary)

Define the trigangles of the neck; include the important boundaries and contents of each.

Posterior Triangle

ant.: sternocleidomastoid

post.: trapezius

floor: scalene muscles

contents: bracio plexus, subclavian artery & vein

Anterior Triangle

ant.: midline of neck

post.: sternocleidomastoid

contents: thyroid glands, carotid artery, internal jugular vein, sympathetic trunk, vagus nerve hyoid muscles

Sternocleidomastoid

A: Sternum and clavicle

B: Mastoid process of the skull

INN: Accessory nerve (XI)

Action:

- T: flexion of cervical spine

- I: draw head to shoulder, rotate head

Scalene Muscles

A: Anterior - T.P. to C3-C6

Middle - T.P. to C3-C7

Posterior - T.P. of C5-C6

B: Anterior - first rib

Middle - first rib

Posterior - second rib

INN: cervical spinal nerves

Action: T - stabilize head, aid respiraion

I - lateral neck flexion

Sternohyoid

A: sternum

B: hyoid bone

INN: ventral rami C1-C3 spinal nerves (cervical plexus)

Action: depress hyoid bone

Omohyoid

A: Superior border of scapula (near scapular notch)

B: Hyoid bone

INN: cervical plexus

Action: depress and retract hyoid bone

Sternothyroid

A: sternum

B: thyroid cartilage

INN: cervical plexus

Action: depress throid cartilage

Thyrohyoid

A: thyroid cartilage

B: hyoid bone

INN: cervical plexus

Action: depress hyoid bone or elevate thyroid cartilage

Stylohyoid

A: styloid process of the skull

B: hyoid bone

INN: facial nerve (VII)

Action: raise and retract hyoid bone

Mylohyoid

A: mandible

B: hyoid bone

INN: mandibular nerve (V3)

Action: raise tongue

Digastrics

A: Mastoid notch (medial mastoid process)

B: mandible near symphysis

INN: anterior mandibular nerve (V3) & posterior facial nerve (VII)

Action: anterior - open mouth

posterior - raise hoid bone

Geniohyoid

A: mandible

B: hyoid bone

INN: cervical spinal nerves (C1-C2)

Action: elevate hyoid bone and base of tongue

What structures are involved in "thoracic outlet syndrome"?

Compression of neurovascualr bundle passing between the anterior and middle scalene. Bracial plexus may also be compressed.

What is a "neurovascualr bundle" and what are the contents of this "bundle" in the neck?

Neurovascular bundle is a bundle of nerves arteries and veins. In the neck it is made up of the vagus nerve, inferior jugular vein, and the common carotid artery.

What are the primary target organs of the hyoid muscles?

larynx - suspension

tongue - support

What daily activities are effected by the hyoid muscles?

swallowing, respiration, mastication, speech

Give the functions of the larynx.

protective 'sphincter' of trachea

increase pressure of thorax - via abdomen (valsalva manuver)

phonation (raw sound)

Describe the larynx in terms of the ligaments that compose it.

cricotrachial ligament

cricothyroid ligament

thyrohyoid membrane (several ligaments)

vocal ligament - arytenoid to thyroid cartilage

vestibular ligament - make vestibular folds (false vocal folds)

cricovocal membrane

Give and describe the articulations of the larynx.

cricoarytenoid articulation - synovial gliding, rotation, open (abduction) & close (adduction) rima glottidis

cricothyroid articulation - synovial gliding, tilt thyroid cartilage down, change length/tension of vocal folds

Describe the muscles that work on the articulations of the larynx.

posterior cricoarytenoid - open vocal folds/abduction

lateral cricoarytenoid - close vocal folds/adduction

cricothyroid - increase tension/length of vocal cords

vocalis - runs length of vocal ligament

thyroarytenoideus - decrease tension/length of vocal folds

arytenoideus - close vocal folds/adduction

What is the rima glottidis?

The space between the vocal ligaments.

Describe abduction and adduction of the vocal folds.

abduction - opening

adduction - closing

Describe the nerve supply to the larynx.

vagus nerve - motor & sensory

superior larengeal nerve

internal larengeal nerve - sensory above cords

external larengeal nerve - motor to cricothyroid

recurrent laryngeal nerve - motor to rest of laryngeal muscles/ sensory below cords

Describe the folds of the larynx.

vocal folds - ligaments, muscles, mucus membrane (bottom)

vestibular folds - false vocal folds (top)

Give and define the processes involved in speech.

phonation - larynx (raw sound)

ressonance - pharynx/nasal cavity/oral cavity/ nasal sinuses

articulation - mouth/teeth/lips/tongue

Describe the ventricular system of the brain, their arrangement and position and their connections with the subarachnoid space.

Lat ventricle - c-shaped, cerebral hemispheres

3rd ventricle - lat. walls formed by thalamus/hypothalamus

4th ventricle - pyramid shaped, floor of cerebellum, 3 apertures to subarachnoid space

Describe the temporal mandibular joint in terms of the bones involved and the action of the joint.

involves temporal bone and mandible

synovial joint

hinge: opens/closes mouth

gliding: protractin (sticking out) and retraction (pulling in)

Give the layers of the eye.

external (skeleton)

middle (vascular)

internal (retina)

Give the components of each of the layers and their individual function. (eye)

external - sclera, cornea

middle - iris (SANS = opens, PANS = closes), ciliary body, choroid

internal - macula lutea (detailed vision)

Describe the difference between the optic axis and the orbital axis.

optic axis - in line with the macula lutea (line of sight)

orbital axis - in line with the optic disc (axis of rotation)

Give the different refractive media of the eye.

cornea - bends light the most

aqueous humor - constricts (PANS - fast) and dialates (SANS - slow) pupil

lens

vitreous humor

Describe "accommodation".

contraction = loosen suspensory ligament = fatten lens (near)

relax = increase tension = thin lens (far)

Describe the iris, pupillary diameter changes and the muscles involved.

ciliary muscles

sympathetic - opens - lets more light in (slow)

parasympathetic - closes - keeps light out (fast)

What is the "conjunctiva"?

mucus membrane

Give the nerve supply to the extraocular muscles.

oculomotor III, trochlear IV, abducent VI

Describe the lacrimal gland and "tearing", include its nerve supply.

lacrimal gland to lacrimal ducts to eye (CN VII)