Orbit Stephens

Question 1

What is the difference between partial and complete ptosis?

Answer 1

Complete ptosis is complete closure of the eye due to paralysis of levator palpbrae superioris.
Partial ptosis is paralysis of tarsal muscle which inserts on upper lid.

Question 2

What structures drain tears from surface of the eye?

Answer 2

Lacrimal portion of orbicularis oculi sucks tears out of the eye. Upper lid moves tears across cornea and go to lacrimal punctum to drain to lacrimal canaliculi which drains to lacrimal sac to nasolacrimal duct which opens into the inferior meatus of nasal cavity.

Question 3

How does a blow out fracture of the face occur and what is it?

Answer 3

Fracture of the floor of the orbit due to fracture of zygomatic. Cant look up and will have anesthesia on the face. It will trap the infraorbital nerve in the inferior orbital fissure.

Rare occurrence, but the optic canal is compressed compressing optic nerve and artery and it is called traumatic optic neuropathy vision can be lost transiently or permanently

Question 4

Describe the shape of Le Fort I

Answer 4

Le Forte I: transverse fracture of the maxilla and you can move the upper dental arch

Question 5

What are the cardinal signs of gaze?

Answer 5

have patient focus on finger and follow laterally and medially up to left and right down to left and right, back to horizontal. Also bring the finger out and into their face to watch pupil constrict.

H pattern! Both eyes at the same time!

Question 6

What is Horner’s syndrome?

Answer 6

paralysis of the tarsal muscle resulting in slight ptosis and Miosis(pupil constriction) due to paralysis of dilator pupillae, enophthalamos (due to paralysis of orbitalis muscle of muller), Anhidrosis and blushing of face also present

Question 7

How do autonomics get to the lacrimal gland?

Answer 7

Zygomatic nerve communicates between maxillary and lacrimal

Question 8

sphenopalatine ganglion distributes autonomics to what structures?

Answer 8

posterior 2/3 of nasal cavity, nasopharynx, palate

Question 9

How does the sphenopalatine ganglion get its autonomic fibers?

Answer 9

The greater superficial petrosal nerve, a branch from facial supplies pregang parasymp fibers to the ganglion, the post gang parasymp fibers from it go to maxillary to zygomatic and then lacrimal gland.

Deep petrosal comes is post ganglionic sympathetic fibers and merge with greater superficial petrosal forming nerve to pterygoid canal (Vidian nerve)

Question 10

Le Forte II

Answer 10

Pyrimidal fracture including orbital marginn

Question 11

Le Forte III:

Answer 11

Craniofacial dysjunction with a panda bear appearance. Two black eyes. Severe fractures, concern for brain damage, as face is literally broke from the head.

Blood from nose need to be concerned about CSF coming out as well due to dural tears.

Question 12

What is the periorbita facsia?

Answer 12

Continuous with the endosteal dura

Question 13

Inability to abduct the eye, what nerve and muscle is damaged?

Answer 13

LR and abducens nerve

Can be caused by intracranial pressure
“sundown gaze”

Question 14

What does the frontal nerve split into and where is it from?

Answer 14

Supratrochlear and Supraorbital

From the opthalmic branch of the trigeminal

Question 15

What does trochelar nerve do in the eye?

Answer 15

Innervate superior oblique and sits on top of the muscle

Question 16

What vessels are associated with the cavernous sinus?

Answer 16

Oculomotor 3
Trochlear 4
Abducens 6 
Trigeminal 5.1 5.2 
ICA

Question 17

A patient has external strabismus, complete ptosis and their pupils are dilated and unreactive. What nerve is damaged?

Answer 17

Oculomotor

Question 18

Inability to adduct and depress the eye, what nerve and muscle is damged?

Patient will tend to tilt their head away from the affected eye.

Answer 18

Superior oblique and trochlear nerve

Question 19

Inability to abduct eye and diplopia due to internal strabismus, what muscle and nerve?

Answer 19

Lateral rectus and Abducens

Question 20

Describe corneal/blink reflex.

Answer 20

affects afferent by nasociliary nerve (V)
and efferent by zygomatic branch of 7

Touching the eye should induce blinking of both eyes

Question 21

Are pupillary constriction and thickening of lens parasympathetic or sympathetic responses?

Answer 21

Parasympathetic

Question 22

What is Hyphema?

Answer 22

Presencce of blood in the anterior chamber of the eye due to trauma and rupture of the great arterial circle of the iris. Medical emergency

Question 23

What is a subconjunctival hemorrhage?

Answer 23

rupture of the deep pericorneal plexus and bleeding is restricted to subconjunctival tissue or bulbar fascia

Question 24

Direct light reflex?

Answer 24

Optic nerve, optic tract to the brachium of superior coliliculus to the superior coliculus. Then to Pretectum and constriction is mediated by edinger-westphal nucleus of the occulomotor nerve which goes to ciliary ganglion and then the pupil constricts

Question 25

Dilator reflex?

Answer 25

Retia optic nerve superior colliculus pretectum reticular formation lateral reticulospinal tract and preganglionic symp neurons

Horner’s syndrome

Question 26

What is accommodation?

Answer 26

cortically mediated response.

Triad of accommodating is convergence of gaze and pupillary constriction and thickening of lens

Question 27

What is argyll robertson pupil

Answer 27

accommodating but un reactive

Question 28

What is holmes adie pupil?

Answer 28

tonic pupil that slowly converges parasympathomimetic drugs constrict the tonic pupil and has no effect on normal pupil

Question 29

Papilledema?

Answer 29

pressure on the optic nerve- increased crainial pressure is cause

Question 30

What nerves do the corneal reflex test?

Answer 30

V1 and VII

Question 31

What does the central artery supply?

Answer 31

four quadrants of the retina through upper and lower temporal branches and upper and lower nasal branches.
Also supplies anterior optic nerve NOT posterior optic nerve

Question 32

What arteries supply the optic nerve?

Answer 32

posterior ciliary and central retinal arteries which come from the opthalmic artery

Question 33

Where do all extraocular muscles attach except one and what is the one?

Answer 33

All attach to the annulus tendinius except for the inferior oblique

Question 34

What is the thickest wall of the orbit and what bones form it?

Answer 34

Lateral wall formed by the frontal maxilla, zygomatic lacrimal, sphenoid ethmoid and palatine. The first four were bolded in lecture.