100 concepts

Muscles of the orbit

Superior rectus

inferior rectus

Medial rectus

Lateral rectus

Superior oblique

Inferior oblique

Levator palpebra superior

Superior rectus action

Up and medial

Superior rectus testing

Look laterally, then up

Superior rectus innervation

CN3

inferior rectus action

down and medially

inferior rectus testing

look laterally, then down

inferior rectus innervation

CN3

Medial rectus action

adducts pupil

Medial rectus testing

look laterally

Medial rectus innervation

CN3

Lateral rectus action

abducts pupil

Lateral rectus testing

look medially, then down

Lateral rectus innervation

CN6

Superior oblique action

down and laterally

Superior oblique testing

look medially, then down

Superior oblique innervation

CN4

Inferior oblique action

up and laterally

Inferior oblique testing

look medially, then up

Inferior oblique innervation

CN3

Levator palpebra superior action

elevates upper eyelid

Levator palpebra superior innervation

CN3

Oculomotor nerve palsy affects

Most extraocular muscles

oculomotor nerve palsy manifestations

Ptosis

Fully dilated pupil

Eye is fully depressed and abducted ("down and out") due to unopposed actions of superior oblique and lateral rectus

Trochlear nerve palsy causes paralysis of

superior oblique

Characteristic sign of trochlear nerve injury

Diplopia (double vision) when looking down (going down stairs or reading)

Impaired ability to turn the affected eyeball infero-medially ("up and out"

Abducens nerve palsy causes paralysis of

lateral rectus

Abducens nerve palsy signs

affected eye is adducted by the unopposed action of the medial rectus that is supplied by CN3

What can cause Horner Syndrome

Penetrating injury to neck

Pancoast tumor

Thyroid carcinoma

What nerve is affected in Horner syndrome

Ascending pregganglionic sympathetic fibers (T1 segment [IML] of spinal cord and their synapse in superior cervical ganglion)

Signs of Horner Syndrome

Constriction of pupils (miosis)

Drooping of superior eyelid (ptosis)

Redness and increased temperature of the skin (vasodilation)

Redness and increased temperature of the skin (vasodilation)

Absence of sweating (anhydrosis)

Complications fo otitis media

Hearing diminished

Taste altered

Mastoiditis

Meningitis, temporal lobe abscess, signoid sinus thrombosis

What can cause the altered taste in otitis media

Pressure on chorda tympani

What can cause meningitis in otitis media

Spreading to middle cranial fossa

What can cause sigmoid sinus thrmobosis

Infection moving through the floor of the sinus

If you have a perforation of the tympanic membrane, what can result

Loss of taste over anterior 2/3 of tongue

Decreased secretion of sublingual and submandibular glands

Function of vestibulocochlear organ

Reception of sound

Maintenance of balance

receptors from _____ are responsible for hearing

Cochlea (spiral organ of corti)

Where is spiral organ of corti located

Along basilar membrane

Parts of the balancing aparatus

Utricle

Saccule

Which plane does the anterior semicircular canal receive angular acceleration

Coronal

Which plane does the posterior semicircular canal receive angular acceleration

Sagittal

Which plane does the lateral semicircular canal receive angular acceleration

Lateral

Body's largest endocrine galnd

Thyroid gland

Function of thyroid hormone

Control rate of metabolism (body temperature)

Calcitonin release

Function of calcitonin

Controls calcium metabolism (reduce blood calcium Ca+)

What can happen after a total thyroidectomy

Lower total body temperature

Hypercalcemia

Function of parathyroid hormone

Control metabolism of phosphorus and calcium in blood (increase Ca2+ levels)

In 1-5% of people, an inferior parathyroid gland is located _____ because of their common embryonic origin

deep in the superior mediastinum inside the thymus

What structure is anterolateral to the thyroid gland

infrahyoid muscles

what structure is located posterolateral to the thyroid gland

common carotid artery

what structure is located medially to the thyroid gland

larynx

trachea

pharynx

esophagus

cricothyroid muscle

recurrent laryngeal nerve

What structure is located posteriroly to the thyroid gland

parathyroid glands

Painless midline mass on the anterior aspect of the neck just below the hyoid bone that moves during swallowing together with the thyroid gland because of relation with pre-tracheal layer of cervical fascia and infrahyoid muscles of the neck

Median cervical cyst

What is a median cervical cyst

remnant of thyroglossal canal

treatment of median cervical cyst

surgical excision

what are lateral cervical cysts

remnants of 2nd, 3rd, and 4th grooves and filled up by ectoderm

painless cysts located on the lateral neck along the anterior border of the sternocleidomastoid muscle

lateral cervical cysts

what are lateral cervical cysts also known as

Branchial cysts

T/F: Lateral cervical cysts move during swallowing

FALSE

Treatment of lateral cervical cysts

surgical excision

What are the true vocal cords

vocal folds

what are the 2 larynx folds

vestibular folds

vocal folds

Gap between the vestibular folds

Rima vestibuli

gap between the vocal folds anteriorly and vocal processes of the arytenoid cartilages posteriorly in the larynx

rima glottidis

most narrow place in the larynx

rima glottidis

adductor muscles of the larynx

posterior cricoarytenoid

Function of posterior cricoarytenoid

abducts vocal folds

posterior cricoarytenoid innervation

recurrent laryngal nerve (CNX)

If the recurrent laryngeal nerve is severed, what are the symptoms

Hoarseness

emergency procedure that relieves an airway obstruction

cricothyrotomy

Where is the needle inserted in a cricothyrotomy

below the thyroid cartilage

in a cricothyroitomy, where is a small incision made

cricothyroid membrane

between cricoid and thyroid cartilage

what is the retropharyngeal space other name

Bucco-pharyngeal fascia

Function of retropharyngeal space

Passageway of infection from pharynx to posterior mediastinum

Mortality rate of mediastinitis

90%

axillary sheath is derived from

prevertebral fascia

what is within the axillary sheath

subclavian artery

brachial plexus

what does the brachial plexus pass between

Anteiror and medial scalenus

Most common cause of congenital torticollis

Fibrous tissue tumor in SCM

Symptoms of torticollis

Head turns to the side and the face to turn away from the affected side

what might cause spasmodic torticollis

bilateral combination of lateral neck muscles (usually SCM and trapezius)

What happens in spasmodic torticollis

Involuntary shifting of head laterally or anteriorly

Shoulder usually elevated and anteriorly displaced on the side on which chin turns

What structures are within the posterior triangle of the neck

Veins (external jugular and subclavian)

Arteries (occipital)

Nerves (CN11, trunks of brachial plexus, branches of cervical plexus, phrenic nerve)

Lymph nodes (superficial cervical)

What structures does CN11 supply

Sternocleidomastoid

Trapexius

Function of SCM

turning head to opposite side

Function of Trapezius

Superior fibers elevate, middle fibers retract, and inferior fibers depress scapula

Nosebleed

Epistaxis

Epistaxis most often occurs from _____ in the nose

Anterior nasal septum (Kieselbach's area)

What is in Kieselbach's area

Branches of sphenopalatine, anterior ethmoidal, greater palatine, and superior labial arteries converge

_____ receives opening of the sphenoidal air sinus

Sphenoethmoidal recess

______ receive opening of posterior ethmoidal air cells

Superior meatus

_____ receives openings from frontal and maxillary sinuses and anterior and middle ethmoidal air cells

Middle meatus

What makes up the middle meatus

Infundibulum

Ethmoidal bulla

Semilunar hiatus

_____ receives opening of nasolacrimal duct

Inferior meatus

Infection of _____ can erode the medial wall of the orbit resulting in orbital cellulites that can spread to the cranial cavity

Ethmoidal sinus

In orbital cavity infection may erode structures related to the medial orbital wall such as

Medial rectus muscle

Superior oblique muscle

Nasociliary nerve

What forms the cheeks

lateral, moveable walls of the oral cavity

Zygomatic prominences of hte cheeks over the zygomatic bones

Principal muscle of the cheek

Buccinator

Encapsulated collection of fat superficial to buccinator

Buccal fat pad

What structure pierces the buccinator

parotid duct