Eye Anatomy

Question 1

Which walls of the orbit are most likely to fracture?

Answer 1

Inferior and medial

Question 2

Which muscles move the eyelids and which nerves are they innervated by?

Answer 2

Levator palpebrae superioris- CN3
Orbicularis oculi- CN7

Question 3

What is the name of the dense fibrous tissue supporting the eyelid?

Answer 3

The tarsal plate

Question 4

hat is the difference between a stye and a chalazion?

Answer 4

Stye is an infection of a gland of moll, Zeiss or the eyelash follicle
Chalazion is painless swelling of the eye from obstruction of the tarsal glands

Question 5

What makes up the lacrimal apparatus?

Answer 5

Lacrimal glands, lacrimal ducts and lacrimal cannaliculi

Question 6

What are the components of the tear film?

Answer 6

Surface lipid layer (from meibomian/tarsal glands), middle aqueous layer (from lacrimal glands), inner mucus layer (from goblet cells of conjunctiva)

Question 7

Why is a tear film needed?

Answer 7

Antibacterial properties, reduces friction between ocular surfaces, smooth ocular surface allows uniform light refraction

Question 8

What are the three layers of the eyeball?

Answer 8

Sclera and cornea
Choroid, ciliary body and iris
Retina

Question 9

what are the different layers of the cornea?

Answer 9

epithelium, Bowman’s membrane, stroma, descemet’s membrane and endothelium

Question 10

what drugs can be used to reduce IOP?

Answer 10

beta blockers, alpha agonists, prostaglandin analogues, carbonic anhydrase inhibitors, parasympathometic