Orbit And Cavernous Sinus - 4/7 Neal

Question 1

Post-ganglionics from the SCG to the lacrimal gland travel through what nerves?

Answer 1

Deep petrosal joins greater petrosal to form the vidian nerve

Question 2

Describe the effects of Oculomotor nerve palsy?

Answer 2

Down and out gaze
Dilated pupil
Eyelid must be manually elevated due to ptosis

Question 3

What motions of the eye are not included in the cardinal signs of gaze?

Answer 3

Straight up/down

Question 4

Complete ptosis of the eye may be due to a lesion in what muscle?

From what nerve and what type of fibers?

Answer 4

Levator palpebrae Superioris (LPS)

CN 3, GSE

Question 5

What are the PS responses of the eye?

Answer 5

Pupillary constriction (sphincter pupillae m.)
Thickening of the lens for near vision (ciliary m.)

Question 6

Lesion to the lateral rectus muscle results in what?

superior oblique?

Answer 6

Inability to ABduct the affected eye

When ADducted cannot depress the affected eye

Question 7

Oculomotor nerve palsy has what 3 clinical signs associated with it?

Answer 7

Down and out eye
Complete ptosis
Pupil dilation

Question 8

Loss of consensual light reflex is due to the destruction/lesion of what?

Answer 8

Posterior commissure

Question 9

An aortic or carotid aneurysm can cause what?

What else may cause this symptom?

Answer 9

Decrease in Sympathetic outflow to the dilator pupillae muscle -> therefore pupillary constriction

Pancoast tumor (mass effect)

Question 10

Lesion to what muscle will cause partial ptosis?

Innervated by what?

These fibers originate where?

Answer 10

Tarsal muscle of Muller

POST-ganglion if Sympathetic fibers

T1

Question 11

What is anhydrosis?

If anhydrosis is absent, what else can you look for as a clinical Sx?

Answer 11

Lack of sweating

Flushing of the face (dilation of facial blood vessels) to half of the face

Question 12

What is an Argyll Robertson pupil?

Answer 12

Unreactive to light with

Normal accommodation

Question 13

What kind of response is accommodation? For what?

What is its associated triad?

Answer 13

Cortically-mediated response for near vision

Convergence of gaze
Pupillary constriction
Thickening of lens

Question 14

What is a Holmes-Adie Pupil?

Answer 14

Topically slow reacting pupil to light
Normal accommodation
Transient, usually due to infection

Question 15

What is hyphema?

Damage to what vessel causes it?

Answer 15

Pooling of blood in the anterior chamber of the eye

Arterial circle of iris

Question 16

Grade 1 hyphema?

3?

Answer 16

Less than 1/3 volume in ant. Chamber

greater than 1/2 volume in anterior chamber

Question 17

Damage to what vessel causes subconjunctival hemorrhage?

Where is bleeding restricted to?

Answer 17

Deep pericorneal plexus

Subconjunctival tissue or bulbar fascia

Question 18

Damage to the superficial pericorneal plexus causes what?

Answer 18

Conjunctivitis

Question 19

What structures are involved in a Le Fort 1 fracture?

Where does the fracture line pass through?

Answer 19

Horizontal maxillary fracture, separates teeth from upper face

Alveolar ridge, lateral nose and inferior wall of maxillary sinus

iMAN

Question 20

What kind of fracture is Le Fort 2?

Fracture passes through what?

Answer 20

Pyramidal w/teeth at the base and nasofrontal suture at its apex

Alveolar ridge, lateral walls of maxillary sinuses, inferior orbital rim and nasal bones

LMAIN

Question 21

Le Fort 3 fracture involves what?

Passes through what structures?

Answer 21

Craniofacial disjunction

Nasofrontal suture, maxillo-frontal suture, orbital wall, zygomatic arch

ZMON

Question 22

The Ophthalmic artery comes off of what?

What are its branches?

Answer 22

ICA

Supraorbital
Posterior ethmoidal a.
Anterior ethmoidal a.
Lacrimal
Short ciliary arteries

Question 23

What veins drain into the cavernous sinus?

Answer 23

Superior and inferior ophthalmic veins

Question 24

Occlusion of the central retinal artery may cause what?

Answer 24

Abrupt, painless presentation

Cherry red macula seen on exam

Question 25

What nerve in the eye is vulnerable to ischemia secondary to orbital fracture?

Answer 25

Inracanalicular portion of the optic nerve

Question 26

What are the branches off of V1? Where does it exit the skull?

Answer 26

Nasociliary Frontal (Supraorbital and supratrochlear) Lacrimal Superior orbital fissure

Question 27

Where does the maxillary nerve exit the skull?

Answer 27

Foramen rotundum

Question 28

Where does V3 exit the skull? What does it supply?

Answer 28

Foramen ovale Muscles of mastication

Question 29

The corneal reflex afferent component is sensed by what nerve? Efferent component?

Answer 29

V1 (Nasociliary nerve) Zygomatic and Temporal branch of CN 7 IN by 5 OUT by 7

Question 30

Blow-out fractures cause Herniation of orbital structures such as ____ into the maxillary sinus?

Answer 30

Periorbita Inferior oblique Inferior rectus Orbital fat pad

Question 31

All extraocular muscles are attached to the tendinous ring (annulus tendinius) except what?

Answer 31

Inferior oblique muscle

Question 32

Increased intracranial pressure may compress what nerve? Causes what?

Answer 32

Abducens nerve (CN 6) Paralysis of lateral rectus m.

Question 33

What is the main sensory (GSA) nerve to the eyeball?

Answer 33

Nasociliary nerve

Question 34

What is the chief artery of the orbit? Where does it branch from?

Answer 34

Opthalmic a. ICA

Question 35

The opthalmic artery gives rise to what arteries which supply the optic nerve?

Answer 35

Posterior ciliary a | Central retinal a

Question 36

The central retinal artery provides what with a centrifugal vascular supply? What does it not supply?

Answer 36

Anterior optic nerve Posterior optic nerve

Question 37

How does the central artery supply the 4 quadrants of the retina?

Answer 37

Through upper and lower temporal branches | Upper and lower nasal branches

Question 38

What forms the superior ophthalmic vein? Where does it drain? What else drains here?

Answer 38

Supraorbital and angular veins Cavernous sinus Central vein of the retina

Question 39

The afferent component of the direct light reflex is mediated by what? Where does the information first synapse? Then where?

Answer 39

Optic nerve Superior colliculus Pretectum

Question 40

The efferent component of the direct light reflex is mediated by what? What nucleus? What ganglion?

Answer 40

PS CN 3 Edinger-Westphal Ciliary ganglion

Question 41

Preganglionic sympathetic neurons for pupillary dilation are located where?

Answer 41

ILCC at T1

Question 42

What is the site called for focusing detailed vision?

Answer 42

Fovea centralis

Question 43

What causes papilledema? Result?

Answer 43

Increased intracranial pressure Swelling/edema of the optic disc

Question 44

Sympathetic innervation to the lacrimal gland originates where? Where do Pre-ganglionics synapse? Post-ganglionic?

Answer 44

Sympathetic trunk SCG Travel through SPG but do not synapse

Question 45

Blow-out fractures cause Herniation of what into the maxillary sinus?

Answer 45

Inf oblique m. Inf rectus m. Orbital fat pad

Question 46

Describe draining of tears from the eye starting from the surface:

Answer 46

Lacrimal canaliculi -> lacrimal sac -> nasolacrimal duct -> inferior meatus Csdim

Question 47

Diplopia due to internal strabismus is the result of what lesion?

Answer 47

Abducens nerve

Question 48

External strabismus is from lesion to what?

Answer 48

Oculomotor nerve

Question 49

When a patient presents with their head tilted away from an eye that is stuck up and in, what lesion exists?

Answer 49

Trochlear nerve

Question 50

What does the lacrimal artery give off?

Answer 50

Recurrent meningeal a.