Eye.2 Flashcards
What are the 3 parts that make up the eyeball?
sclera & cornea
uvea
retina
What is the structure and function of the Sclera?
‘white of eye’- extrinsic muscles insert here
protection
maintains shape
What is the Limbus?
junction where sclera meets cornea- important for aqueous humour flow, entry point of glaucoma/ cataract surgery
What is the structure and function of the Cornea?
large supply of sensory nerve fibers, focusing light on retina
What is the Corneal Reflex?
closing of eyelids when cornea touched- poor blood supply
last reflex to go (patient fatality)
What is a Corneal Ulcer?
serous eye condition, damage to cornea- rupture of eye/ removal (enucleation)
What are the features of the Uvea?
vascular layer beneath protective
pigmented
firmly attached- optic nerve
What are the layers of the Eye?
Inner- retina
Middle- uvea
Outer- sclera and cornea
What are the 3 parts the Uvea divided into?
choroid
ciliary body
iris
What is the structure and function of the Choroid (Uvea)?
prevents light escaping, contains blood vessels supplying eyeball
darkly pigmented layer
What is the suspensory ligament?
a continuation of ciliary body, supports lens
What is the structure and function of the Ciliary Body (Uvea)?
contains smooth muscle fibres, controls shape and thickness of lens
Define Accommodation
when lens changes shape. focusing on image
via ciliary body, focusing image onto retina
What is the structure and function of the Iris (Uvea)?
free edges form pupil, iris muscles contract
oculomotor nerve- nerve supply to the iris
What is Mydriasis?
dilation of pupil
What is Miosis?
constriction of pupil
What does the pupil allow?
light into retina
