Orbit

Question 1

What causes complete ptosis of the eyelid?

Answer 1

destruction of the occulomotor nerve or one of its branches to the levator palpebrae superioris muscle

Question 2

what nerve innervates the levator palpebrae superioris muscle?

Answer 2

occulomotor nerve

Question 3

what innervates the tarsal muscle?

Answer 3

postganglionic sympathetic fibers

Question 4

what is Horner’s syndrome and what is a classic sign?

Answer 4

usually involves paralysis of the tarsal muscle; slight ptosis

Question 5

where are the ciliary glands located?

Answer 5

in the subcutaneous layer of the orbit

Question 6

What sends the preganglionic parasympathetics to the sphenopalatine ganglion?

Answer 6

the superior salvatory nucleus

Question 7

what is the pre-ganglionic parasympathetic nerve that will eventually synapse in the sphenopalatine ganglion?

Answer 7

greater superficial petrosal nerve

Question 8

which nerve does the greater superficial petrosal nerve branch off of?

Answer 8

facial nerve (CN VII)

Question 9

where do the postganglionic parasympathetic fibers go after leaving the sphenopalatine ganglion?

Answer 9

to the lacrimal gland- via the maxillary, zygomatic, and lacrimal nerves

Question 10

what sends postganglionic sympathetic fibers to the internal carotid plexus and eventually the sphenopalatine ganglion?

Answer 10

superior cervical ganglion

Question 11

what is the post-ganglionic sympathetic nerve that will eventually travel to the spehnopalatine ganglion?

Answer 11

deep petrosal nerve

Question 12

what do you get when you fuse the greater superficial petrosal nerve and the deep petrosal nerve?

Answer 12

vidian nerve

Question 13

The nasolacrimal duct empties tears into what?

Answer 13

inferior meatus

Question 14

forces applied to the temporal, maxillary, and frontal regions are transmitted where? and cause what?

Answer 14

to the optic canal and cause bony deformations

Question 15

what portion of the optic nerve is the most frequent site of injury in cases of traumatic optic neuropathy?

Answer 15

the intracanalicular portion of the optic nerve

Question 16

what does traumatic optic neuropathy result in?

Answer 16

immediate or slowly progressive loss of vision in the affected eye

Question 17

what does the inferior orbital fissure convey?

Answer 17

the infraorbital artery, infraorbital nerve, and the zygomatic nerve

Question 18

what does the superior orbital fissure convey?

Answer 18

CN III, IV, first part of V, and VI

Question 19

what causes a blow-out fracture?

Answer 19

trauma to the front of the eyeball or a depressed fracture of the zygomatic bone (which is displaced medially

Question 20

Which le forte fracture is an extensive trnasverse fracture of the face involving many facial bones and both orbits (panda bear appearance)?

Answer 20

Le forte type III

Question 21

which le forte fracture is a transverse fracture of the maxillae just above the alveolar processes?

Answer 21

le forte type I

Question 22

which le forte fracture is a pyramidal-shaped fracture of the maxillae usually involving part of the medial margin of one of the orbits?

Answer 22

le forte type II

Question 23

paralysis of the levator palpebrae superioris results in what?

Answer 23

complete ptsosis

Question 24

paralysis of the superior rectus results in what?

Answer 24

inability to abduct and elevate the affected eye

Question 25

paralysis of the medial rectus results in what?

Answer 25

inability to adduct the affected eye

Question 26

paralysis of the inferior rectus results in what?

Answer 26

inability to abduct and depress the affected

Question 27

paralysis of the inferior oblique results in what?

Answer 27

inability to adduct and elevate the affected eye

Question 28

paralysis of the superior oblique results in what?

Answer 28

inability to adduct and depress the affected eye

Question 29

paralysis of the lateral rectus results in what?

Answer 29

inability to abduct the affected eye

Question 30

if a patient presents with complete ptosis of the eyelid, external strabusmus, and the eye is directed outward, dilated and unreactive pupils, what do they have?

Answer 30

occulomotor palsy

Question 31

if a patient presents with the inability to adduct and depress the eye (inability to look in and down)

Answer 31

trochlear palsy

Question 32

if a patient has an inability to abduct the affected eye what do they have?

Answer 32

abducens palsy

Question 33

what are the causes of hydrocephaly?

Answer 33

it is congenital

Question 34

hydrocephaly causes compression of what nerve?

Answer 34

CN VI

Question 35

Compression of CN VI causes what?

Answer 35

sundown gaze

Question 36

what is the blink reflex important for?

Answer 36

testing brain stem function

Question 37

what is another name for the blink reflex?

Answer 37

direct and consensual corneal reflex

Question 38

what is the afferent nerve of the corneal reflex?

Answer 38

nasocilliary nerve ( CN V)

Question 39

what is the efferent nerve of the corneal reflex?

Answer 39

zygomatic branch of the facial nerve

Question 40

what is the chief blood supply to the orbit?

Answer 40

the opthalmic artery

Question 41

what is the blood supply of the optic nerve?

Answer 41

the central retinal artery

Question 42

the presence of blood in the anterior chamber of the eyeball usually due to trauma and rupture of the great arterial circle of the iris

Answer 42

hyphema

Question 43

what vessel is involved with a hyphema?

Answer 43

arterial circle of iris

Question 44

rupture of the deep pericorneal plexus- bleeding restricted to the subjunctival tissue

Answer 44

subconjunctival hemorrhage

Question 45

what vein in the orbit leads to the cavernous sinus?

Answer 45

superior opthalmic vein

Question 46

where is the maxillary sinus located?

Answer 46

beneath the orbit