Opthalmology

Question 1

What are the 2 groups of tissues in the eye?

Answer 1

Adnexa and Globe

Question 2

Define adnexa

Answer 2

Group of tissues around the eye (protect, support, and assist function of globe

Question 3

What coordinates the eye movements?

Answer 3

Medial Longitudinal Fasciculus (CNS)

Question 4

Describe the innervation of extra ocular muscles of the eye

Answer 4

Antagonistic muscles have reciprocal innervation

Question 5

What muscles are innervated by CN III?

Answer 5

Dorsal, Medial, Ventral Rectus + Ventral oblique

Question 6

The dorsal oblique is innervated by CN _______

Answer 6

IV

Question 7

Which CN innervates the Lat Rectus?

Answer 7

VI

Question 8

Which muscle forms a cone that envelopes and retracts the globe into the orbit, is absent in primates/birds/snakes and is innervated by CN VI?

Answer 8

Retractor bulbi

Question 9

What protects the surface of the globe and spreads tears throughout the cornea?

Answer 9

Eyelids

Question 10

What reflexes facilitate eyelid closure?

Answer 10

Corneal, Palpebral, Dazzle

Question 11

Subcortical reflex means it is processed in which part of the brain?

Answer 11

Midbrain

Question 12

Which glands line the lid margin?

Answer 12

Meibomian glands

Question 13

Which eyelid is most mobile in avian and reptile species?

Answer 13

Lower

Question 14

What is the term for eyelids sealed at birth?

Answer 14

Physiologic Ankyloblepahron

Question 15

When do eyelids begin to open postpartum?

Answer 15

10-14 days

Question 16

What lines the outer and inner surface of the TE?

Answer 16

Conjuctiva

Question 17

Where is the TE located in domestic species?

Answer 17

Ventromedial

Question 18

What is the outer oily layer produced by meibomian glands?

Answer 18

Precorneal tear film

Question 19

List 3 functions of the tear film?

Answer 19

Hydration
Lubrication
Oxygen and nutritional support

Question 20

What is the medical term for dry eye?

Answer 20

Keratoconjuctivitis sicca

Question 21

List the clinical signs of dry eye

Answer 21

Mucupurulent ocular discharge, dry corneal surface

Question 22

What is the outer/fibrous coat of the eye composed of ?

Answer 22

Cornea, sclera, limbus

Question 23

How does the cornea stay clear?

Answer 23

Lack of vessels and pigment and non-keratinized epithelium

Question 24

How are the corneal stroma collagen fibrils organized?

Answer 24

Lattice-like and equidistant to permit light transmission

Question 25

Describe the cornea layers

Answer 25

Epithelium - strat squamous/hydrophobic Stroma - hydrophilic can uptake fluorescein

Question 26

What is another name for the corneal endothelium?

Answer 26

Descemet’s membrane

Question 27

If there is loss of protection against Stroma hydration, what happens?

Answer 27

Corneal edema

Question 28

Why are corneal ulcers so painful?

Answer 28

Cornea is highly innervated

Question 29

List some clinical signs of ocular pain

Answer 29

- blepharospasm - epiphora - TE Elevation

Question 30

The afferent aspect of the blink reflex is by which branch of CN V?

Answer 30

Opthalmic (V1)

Question 31

What is the efferent innervation to the blink reflex?

Answer 31

Facial n

Question 32

List the portions of the anterior urea

Answer 32

Iris and ciliary body

Question 33

What is the shape of the pupil dependent on?

Answer 33

Predator vs prey species

Question 34

What structure is most common in herbivore’s anterior uvea?

Answer 34

Granula Iridica - corporta nigra

Question 35

Which muscle constricts the pupil?

Answer 35

Sphincter - parasympathetic

Question 36

What muscle opens the pupil?

Answer 36

Dilator - sympathetic

Question 37

Mydriasis =

Answer 37

dilation

Question 38

Myosis =

Answer 38

Constriction

Question 39

Why do animals have pupils of different shapes?

Answer 39

To direct light to the retina area with the most photoreceptors

Question 40

What are the 2 parts of ciliary body?

Answer 40

Pars plicata and plana

Question 41

Which part of the ciliary body contains the ciliary processes?

Answer 41

pars plicata

Question 42

Describe the function of the ciliary body

Answer 42

Produce aqueous humor and origin of zonular fibers to keep lens in place

Question 43

Where is the aqueous humor?

Answer 43

Anterior and posterior chamber

Question 44

The intraocular pressure of the eye depends on :

Answer 44

Amount of aqueous humor in the eye

Question 45

Describe fluid pathway in the eye

Answer 45

Must flow through the pupil to reach anterior chamber after being made

Question 46

Define glaucoma

Answer 46

High pressure in the eye

Question 47

Describe the anatomy of the lens

Answer 47

- avascular - biconvex

Question 48

Lens function:

Answer 48

Light focus into retina

Question 49

The points where the lens fibers attach to one another:

Answer 49

Suture lines

Question 50

What is the refractive power of the lens impacted by?

Answer 50

Refractive index and curvature

Question 51

What originates from the ciliary body that accommodate the lens?

Answer 51

Zonular fibers

Question 52

An aphakic crescent can be a sign of?

Answer 52

Lens subluxation - area of pupil zone not filled by lens

Question 53

When the lens is no longer attached and may move around the chamber?

Answer 53

Lens luxation

Question 54

The lens accommodate to do what?

Answer 54

Bring image into focus

Question 55

How can accommodation occur?

Answer 55

- changing the curvature or position of lens (symp - distance ; close - parasympathetic)

Question 56

If the ciliary muscles contract, what happens to the lens?

Answer 56

It becomes more rounded - zonular fibers relax

Question 57

What is the transparent, gelatinous material attached to the back of the eye?

Answer 57

Vitreous

Question 58

What is vitreous composed of?

Answer 58

Water, collagen, hyaluronic acid

Question 59

If you have floaters, what is that a sign of?

Answer 59

Degeneration of the vitreous

Question 60

How many layers does the retina have?

Answer 60

10

Question 61

What does the tapetum do?

Answer 61

Acts like mirror to reflect light

Question 62

Where is the lucidum/ what is it part of?

Answer 62

Choroid

Question 63

Rods are responsible for ?

Answer 63

Night vision - black and white

Question 64

Cones are responsible for what ?

Answer 64

Day vision and color