1-2 Scott

Question 1

List the 4 layers of the Limbal region of the eye from posterior to anterior

Answer 1

Bulbar limbus

Corneoscleral limbus

Conjunctival limbus

Optical zone

Question 2

What’s the order of the corneal tear film from deep to superficial?

Which is the largest?

Answer 2

Lipid or oily

Aqueous layer

Mucous layer

Aqueous layer

Question 3

Melanocytes and langerhann’s cells are present in the ___________ _______

This layer is stratified squamous epithelium and 50-60 microns in thickness

Answer 3

Corneal epithelium

Question 4

The epithelium is composed of 5-7 layers, of non-keratinized ________ _______ epithelium.

Answer 4

Stratified squamous

Question 5

When you wear soft cls, you lose surface ________ leading to transient dry eye.

Answer 5

Microvilli

Question 6

The _________ _______ between lateral surfaces of apical cells represent a semipermeable barrier of the corneal epithelium

Answer 6

Tight junctions

Question 7

The wing cells’ posterior surface is _____ while the anterior is ____. They’re attached to adjacent wings via _________ and have gap junctions. Become progressively _________ moving anteriorly towards the surface

Answer 7

Concave. Convex

Desmosomes

FLATTER

Question 8

What helps anchor the basal cells to the basement membrane? Attaches epithelium to underlying stroma

Answer 8

Hemidesmosomes

Question 9

What are the palisades of Vogt?

Answer 9

Stem cell depot for cornea and bulbar conjunctiva

Question 10

What layer of the cornea is 8-12um thick, believed to supply structural support, random collagen fibers, does NOT regenerate, and CANNOT be stripped away from stroma as a continuous sheet???

Answer 10

Bowman’s layer

Question 11

What comprises 90% of corneal thickness? 450-500um with collagen, keratocytes, ground substance.

Answer 11

Stroma

Question 12

How many collagen lamella at 2um each are organized in the stroma?

Answer 12

250…2um each..500um

Question 13

What maintains ground surface of stroma?

What pulls aqueous humor into cornea?

Answer 13

Keratocytes

Glycosaminoglycans (GAGS)

Question 14

In advanced keraticonus the corneal protrusion may cause angulation of the lower lid on down gave is called what?

Answer 14

Munson’s sign

Question 15

What differentiates an ulcer from an abrasion?

Answer 15

Ulcer has damage within stroma

Abrasion is just on the anterior surface, nothing below is hurt

Question 16

What is the basement membrane of Endothelium in the cornea?

Does it regenerate if damaged?

Anterior is laid down before birth, posterior is ________ laid down after birth.

Terminates abruptly at ________ line

Answer 16

Descemet’s

YES

Unbanded

Schwalbe’s

Question 17

Where does the cornea get its’ nutrients?

Also relies on nutrients from vasculature at peripheral cornea

Answer 17

Tear film and aqueous humor!

Question 18

The basal portion of what cell secretes Descemet’s membrane?

Answer 18

Corneal endothelium

Question 19

Anterior ciliary veins in the conjunctiva drain to _______ and _________.

Answer 19

Muscular veins and rectus muscles

Question 20

Where does the scleral contact lens rest?

Answer 20

On the bulbar conjunctiva and the underlying sclera

Question 21

What is ablated using laser in LASIK?

Answer 21

Anterior stroma

Question 22

Sensory innervation from the cornea is conveyed via what nerves?

Answer 22

Long posterior ciliary nerves

Question 23

Small radial branches extend into the middle and anterior stroma form the ___________ just below Bowman’s layer

The naked nerve fibers pass through Bowman’s layer to enter the corneal epithelium where they form an __________

Answer 23

Subepithelial plexus

Intraepithelial plexus

Question 24

Are there any sensory nerve fibers present in the posterior stroma, Descemet’s membrane, and corneal endothelium?

Answer 24

NO NONONONO