• frontal (orbital plate forms roof)
• maxillary bone (floor)
• zygomatic bone
• sphenoid bone
• ethmoid bone
• lacrimal bone

• optic canal
• superior orbital fissure
• inferior orbital fissure

• optic nerve
• opthalamic artery

• oculomotor N.
• trochlear N.
• abducens N.
• branches of CN V1
  • frontal branch
  • nasociliary branch
  • lacrimal branch
• superior opthalamic vein

What transmits through the inferior orbital fissure?

Define a blow out fracture, its cause, and the clinical sign of it.

• definition- fracture of the floor of the orbit (maxillary bone)
• cause- trauma to the face
• clinical sign- eye drops into maxillary sinuses

Ask patient to first look laterally, then up. The muscle is strongest when pupil is already directed laterally.

Ask patient to look laterally, then downard. The muscle is strongest when eye is already directed laterally.

• medial rectus
• superior rectus
• inferior rectus
• inferior oblique

1. leaves the brainstem
2. travels to lateral wall of cavernous sinus
3. enters orbit via superior orbital fissure
4. divides into superior and inferior divisions

• lacrimal
• frontal
  • supraorbital
  • supratrochlear
• nasociliary

1. travels within cavernous sinus in intimate contact with ICA
2. enters orbit via superior orbital fissure

• sensory to lacrimal gland and upper eyelid
• carry post ganglionic parasymp. axons from pterygopalatine ganglion for innervation of lacrimal gland

• supraorbital
• supratrochlear

The lateral walls of the nasal cavity are made of up what?

• superior concha
• middle concha
• inferior concha

CN IX

CN X

CN XI

internal jugular V.

optic canal

superior orbital fissure

foramen rotundum

foramen ovale

foramen spinosum

Name the foramina of the middle cranial fossa.

superior orbital fissure

foramen rotundum

foramen ovale

foramen spinosum

carotid canal

foramen lacerum

foramen magnum

hypoglossal canal

jugular foramen

1. Superior and inferior saggital sinuses course along falx cerebri
2. Inferior sinuses joined by greater cerebral vein to form straight sinus
3. All three enter at the confluence of sinuses
4. Confluence of sinuses become the right and left transverse sinuses
5. Drain into the sigmoid sinuses
6. they will drain into the internal jugular vein

They are connected to the veins of the face, allowing infections to spread into the cavernous sinuses causing a clotting of blood known as the cavernous sinus thrombosis.

1. extends anteriorly
2. cross masseter muscle
3. pierce buccinator muscle
4. pierce oral mucus membrane to open into the mouth opposite the second upper molar tooth

Describe the innervation of the parotid gland

1. Parasympathetic preganglionic fibers arise from CN IX
2. synapse in the otic ganglion, giving rise to postganglionic fibers
3. Reach the gland via auriculotemporal N(branch of CN V3)

Name the three portions of the orbicularis oculi and their functions.

• palpebral part- close eye gently (blink)
• orbital portion- close eye tightly for protection (wink)
• lacrimal portion- remove tears from eye during blinking

• raise eyebrows
• close eyes lightly or tightly
• show teeth or purse lips as in whistling
• smile, pout, frown
• pull corners of mouth lateral and inferiorly to raise the skin on the neck

• symptoms- lancinating, excruciating pain along distribution of division of CN V
• cause- vascular anomaly that compresses sensory root of CN V

• condyle of mandible
• mandibular fossa and tubercle of temporal bone
• fibrocartilaginous articular disc

• elevation/depression
• protrusion/retraction

The condyle and the disc move anteriorly to lie just under the articular tubercle while the condyle rotates on the disc.

Masseter (origion, insertion, innervation, action)

• origin- zygomatic arch
• insertion- ramus of mandible
• innervation- CN V3
• action- elevate jaw/close mouth

What clinical test is used to test for nerve function of CN V3?

Temporalis (origin, insertion, innervation, action)

• origin- temporal fossa of skull
• insertion- coronoid process of mandible
• innervation- CN V3
• action- elevate and retract jaw

• origin- sphenoid bone
• insertion- neck of mandible and capsule, articular disc of TMJ
• innervation- CN V3
• action- open and protrude mandible, so when used alternately, they produce grinding (side to side) motion

• origin- maxilla and spenoid
• insertion- angle and ramus of mandible
• innervation- CN V3
• action- elevate mandible and side to side movements in chewing

• anterior belly of digastric
• geniohyoid
• mylohyoid

Remember, these muscles are suprahyoid muscles, so the hyoid must be stabilized to depress mandible.

• lingual N.
• inferior alveolar N.
• auriculotemporal N.
• buccal N.
• otic ganglion

1. Enters mandibular foramen
2. Terminates when exits the mental foramen, becoming the mental N.

The mylohyoid N, which supplies the mylohyoid and the anterior belly of the digastric muscle.

1. carries postganglionic parasympathetic fibers from the otic ganglion to the parotid gland
2. Has two roots that surround the middle meningeal A.

1. preganglionic axons will leave via CN IX
2. axons will leave CN IX in its tympanic branch to form the tympanic plexus at middle ear
3. One nerve branches off the tympanic plexus: the lesser petrosal N.
4. lesser pertrosal N. pass thru foramen to join otic ganglion
5. Postganglionic fibers from teh otic ganglion join the auriculotemporal N. to distribute to parotid gland

• Muscles of mastication
  • masseter
  • temporalis
  • lateral pterygoids
  • medial pterygoids
• Tensor tympani
• Tensor veli palatini
• mylohyoid
• anterior belly of digastric

• Location- digastric triangle, deep to mandible
• Ducts open into mouth under anterior end of tongue at its frenulum

• location- inferior to sublingual fold in mouth
• many ducts that open into sublingual fold

• origin- genial tubercle of mandible
• insertion- hyoid
• innervation- C1 fibers

Genioglossus (origin, insertion, innervation, action)

• origin- genial terblce of mandible
• insertion- entire length of tongue
• innervation- CN XII
• action- protrude tongue

• innervation- CN XII
• action- depress tongue

Orbital plate of frontal bones

ethmoid bone

body and lesser wings of sphenoid bones

Crista galli

Cribiform plate

Anterior clinoid processes

The anterior clinoid processes serve as the attachment points for what structure?

Sphenoid bone

temporal bones

Occipital

Temporal

petrous (inside skull)

squamous (lateral)

tympanic

mastoid

Innervation of ciliary muscle and sphincter pupillae

1. origin in superior cervical ganglion
2. post ganglionic fibers travel to plexus surrounding ICA
3. before ICA enters carotid canal, fibers leave as deep petrosal N.
4. Deep petrosal N. joins with greater petrosal N. (branch of CN VII) to form N. to pterygoid canal
5. N. to pterygoid canal pass through pterygopalatine ganglion (site of parasympathetic fibers of CN VII synapse)
6. branches of ganglon distribute to branches of CN V2
7. branches for orbit enter some of the CN V1 branches (ex: long ciliary N's for dilator pupillae)

Cause and symptoms of Horner's syndrome

• cause- damage to sympathetic NS (ex: tumor to stellate ganglion such as apical lung tumor/Pancoasts tumor)
• symptoms
  • ptosis
  • pupillary constriction
  • flushed face
  • dry face

Central Retinal A. 

Ciliary A's

Lacrimal A.

Supraorbital A.

Ethmoid A's

1. transverse superior orbital fissure
2. Communicate with pterygoid plexus of veins deep in cheek
3. both combine to enter into cavernous sinus
4. indirectly communicate with facial V. tributaries

middle ethmoid sinus

anterior ethmoid sinus

frontal sinus

maxillary sinus

Opening for sphenoid sinus

opening for posterior ethmoid sinus

1. Exit middle cranial fossa via foramen rotundum, entering pterygopalatine fossa
2. joined by the N. to pterygoid canal
   1. greater petrosal N. (parasymp. of CN VII)
   2. deep petrosal N. (symp. from ICA plexus)
3. Parasymp. synapse at pterygopalatine ganglion attached to CN V2 in ptyergopalatine fossa
4. Gives off branches

1. orbit
2. nasal cavity (sphenopalatine N.)
3. hard and soft palates (greater and lesser palatine N.'s)
4. face (infraorbital N.)

frontal

sphenoid

Describe the roof of the tympanic cavity

Tegmental wall formed by the tegmen tympani, a thin plate of bone that separates the tympanic cavity from the floor of the middle cranial fossa

Jugular wall, a thin layer of bone separating the tympanic cavity from the IJV (IMPORTANT CLINICAL RELATIONSHIP)

• promontory
• oval window
• round window

• contents
  • opening for auditory tube
  • opening for canal of tensor tympani muscle
• thin layer of bone separating the tympanic cavity from the carotid canal (ICA)

• opening into mastiod air cells (aditus antrum)
• opening/pyramid for stapedius muscle
• opening for chorda tympani N.

• lateral 1/3- cartilaginous
• medial 2/3- bony

• auricolotemporal branch of CN V
• facial
• vagus
• glossopharyngeal

It is lined with mucous membrane continuous with the auditory tube and mastoid air cells. Infection of the middle ear could spread to the mastoid sinuses.

• cause- hardening around stapes at oval window
• result- impede stapes movement, leading to increased deafness

Tensor tympani (ossicle it attaches to, innervation, action)

• innervation- CN V3
• action- prevent damage by reducting amplitude of vibrations
• attaches to malleus

• innervation- CN VII
• action- dampen large vibrations in the bone
• attaches to base of stapes

• tympanic plexus formed by tympanic N.
• bracnh of CN IX b4 it transverses the jugular foramen

Function of chorda tympani N.

• taste of anterior 2/3 of tongue
• preganglionic parasympathetic N. supply to sublingual and submandibular glands

Composition of auditory tube

1/3 bony part (near middle ear)

2/3 cartilagenous part (opens into nasopharynx)

When is the cartilagenous part of the auditory tube opened? What muscles open it?

• open during swallowing or yawning
• opened by tensor veli palatini, levator veli palatini, salingopharyngeus

• epidural abscess
• meningitis
• brain abscess

Sympathetic innervation to lacrimal gland

Composition of inner ear

Membranous labyrinth within the bony labyrinth which is within the temporal bone

• Portions
  • cochlea
  • vestibule
  • semicircular canals
• filled with perilymph (similar to CSF- low potassium)

Constituents of the vestibular apparatus

• semicircular ducts
• utricle
• saccule

Nasopharynx

Oropharynx

Laryngopharynx

The gag reflex, causing movement of the uvula, is used to clinically test for the function of what Nerve? What happens if this nerve is injured?

• vagus N.
• with injury, uvula deviate away from side of the injury

What muscles are found within the soft palate?

• tensor veli palatini
• levator veli palatini
• musculus uvuli

• tensor veli palatini- CN V3
• levator veli palatini- CN X
• musculus uvuli- CN X

auditory tube

• origin- torus of auditory tube
• insertion- thyroid cartilage
• innervation- vagus N.
• action- elevate pharynx during swallowing

• origin- torus of auditory tube
• innervation- vagus N.
• action- elevate soft palate during swallowing

• form arch which marks the boundary between oral cavity and oropharynx
• aka: bound the isthmus faucium or entrance of the throat

extend inferiorly from sides of soft palate

• palatoglossal fold/muscle
• palatopharyngeal fold/muscle
• posterior 1/3 of tongue
  • lingual tonsils
• epiglottis
  • one median, two lateral glossoepiglottic folds
• palatine tonsils

• one median glossoepiglottic fold
• two lateral glossoepiglottic folds

valleculae epiglotticae

• tonsilar fossa, between palatoglossal and palatopharyngeal arches
• end near the angle of the mandilbe (ex: jugulodigastric node)

• posterior wall- continuous with oropharynx
• anterior wall- composed mainly of larynx

• valleculae epiglotticae (oropharynx)
• piriform recess (laryngopharynx)

Form channel to direct solids and liquids from the oral cavity around the raised laryngeal inlet and into the esophagus

• medial borders- arytenoid cartillage and aryepiglottic folds
• lateral borders- side wall of pharynx

Act as a sphincter that must be relaxed in order to swallow

Inhalation of food and eventually acute respiratory infections

pharyngeal constrictor muscles (innervation, function)

• innervation
  • sensory- CN IX
  • motor- CN X
• action- act in unison to propel food toward the esophagus

CN IX

CN X

• internal laryngeal branch of superior layrngeal N.
• superior laryngeal A.(branch of sup. thyroid A.)

• sound production
• act as sphincter to close airways during swallowing, preventing aspiration of food and liquids

• only complete cartilagenous ring in respiratory system
• posterior lamina portion and anterior arch portion
• singlet ring shape

• thyroid cartilage via cricothyroid membrane
• 1st tracheal ring via cricotracheal ligament

• thyroid
• cricoid
• epiglottis
• arytenoid cartilages
• cornicate and cuneiform cartilages

• hyoid bone via hyoepiglottic ligament
• tongue via one median and two lateral glosso-epiglottic folds

What structures attach to the vocal processes of the arytenoid carilages?

Function of the muscular process of arytenoid cartilage

point of insertion of muscles that move arytenoid cartilages

nodules on aryepiglottic folds

Joints of the larynx

cricothyroid

cricoaryntenoid

• composition
  • cricoid cartilage
  • inferior horns of thyroid
• action- rotation and gliding of thyroid cartilage relative to cricoid

Movement of cricoarytenoid joints

What are the subdivisions of the internal structure of the larynx?

• vestibule/supraepiglottic region
• glottis
• subglottic region

epiglottis

aryepiglottic folds

vestibular folds

• vocal cords
• rima glottis

passage between two vocal folds

Attachment points of vocal ligament

• thyroid cartilage (ant.)
• vocal process of arytenoid cartilage (post.)

Relation between the vocal cord and ligament

Ligament forms the skeleton for the cord/fold

• Thyroid cartilage
• Arytenoid cartilage

Part of protective mechanims to close off the larynx during swallowing.

suprahyoid muscles

infrahyoid muscles

Name the muscles that are responsible for closing the layrngeal inlet during swallowing.

transverse arytenoid

oblique arytenoid

thyroepigglotic muscles

• transverse arytenoid- close rima glottis
• oblique arytenoid- close rima glottis and tighten aryepiglottic fold
• thryoepiglottic muscle- tighten aryepiglottic folds

Pull thyroid anterior and inferior in rocking action, thereby increasing tension on vocal cords

thyroarytenoid

vocalis muscle

During what actions would the vocalis muscle be active?

whispering

phonation

singing

Going superior, the oblique arytenoid continues on as what muscle?

• ICA
• sympathetic carotid plexus
• CN VI

CN III

CN IV

CN V1

CN V2

submandibular

pterygopalatine

patient walks into office with head tilted to the side opposite of lesion due to paralysis of superior oblique muscle

Innervation to upper teeth

anterior, middle, and posterior superior alveolar branches of V2

Extrinsic muscles of tongue

genioglossus

styloglossus

hyoglossus

palatoglossus

Symptoms of unilateral vocal cord paralysis

hoarseness

breathiness

easily fatiguable voice

pitch change

Common causes of unilateral vocal cord paralysis

malignancy

surgical injury to recurrent laryngeal N.

1. mastoid and occipital nodes drain into superficial cervical nodes
2. superficial cervical nodes drain into the deep cervical nodes

1. sup. and middle thyroid V.'s drain into IJV
2. inf. thyroid V. drain into left brachiocephalic V.

• occipital
• mastoid
• parotid
• submandibular
• submental

ant. to ear along superficial temporal A.

• loc.- inf. to mandible
• assoc. w/ facial A.
• function- drain tongue

carotid sympathetic plexus

C1-C4 spinal N.'s

pharynx

heart via superior cardiac plexus

• location- inf. to chin
• function- drain floor of mouth and tip of tongue

• landmark- C7 vertebrae
• branches
  • C7, T1 spinal N.'s
  • inferior cardiac N.

• landmark- C6 vertebrae
• branches
  • cardiac N.'s
  • C5, C6 spinal N.'s

Name and state the causes of the two types of torticollis

• congenital- fibrosis of SCM due to hyperextension injury at childbirth
• spasmodic- spasm of SCM due to virus

Function of carotid sinus

Branches of 1st part (medial to ant. scalenes) of subclavian A.

vetebral A.

thyrocervical trunk

inferior thyroid A.

transverse cervical A.

suprascapular A.

internal thoracic A.

costocervical trunk

first 2 intercostal spaces

deep back

subclavian V.

phrenic N.

• superficial perineal space of UG triange
  • ex: perineal pt. of vagina
• lower half of anal canal
• upper part of uterus
• anal triangle

Structures that drain into internal iliac lymph nodes

• anal triangle
• mid, lower part of uterus
• deep perineal space of UG triangle
• upper half of anal canal
• upper half of rectum
• prostate
• most of bladder
• pelvic part of vagina

Structures that drain into the aortic lymph nodes

lower half of rectum

superior rectus

levator palpebrae superioris

medial rectus

inferior oblique

inferior rectus