Eye

Question 1

The outermost layer of the eye (2 structures).

Answer 1

For protection.

(1) Sclera (the white part of your eye). 93% of the outer surface. It’s where the extra-ocular muscles attach. Blood vessels.
(2) Cornea. There are 5 layers, it’s transparent because we want to produce a good image. Light comes into the eye and hits the retina.

Question 2

The middle coat of the eye (3 parts).

Answer 2

Vascularity and nutritive purposes.

(1) Choroid (covers the inside of the sclera) thin, highly vascular. Thickens near the front of the eye (ciliary body).
(2) Ciliary bodies attach to the lens. They have ligaments which attach to the lens. Depending on the strength of the ligaments, it changes the lens. If you need to focus, ligaments need to be concaved
(3) Iris (aka diaphragm) change diameter to let through only a certain amount of light (the pupil)

Question 3

The inner coat of the eye

Answer 3

The retina. The retina has 2 layers, inner layer and outer layer. The outer layer is the pigment layer. The inner is the neural layer- rods and cones have the part that sends the image to the brain.

Question 4

Fluid that sits in the eye (2)

Answer 4

(1) Vitreous humor (back of the eye) water and electrolytes.
(2) Anterior portion- Aqueous humor. Needs to be drained on a daily basis, drains into lymphatic vessel. If it doesn’t drain, causes intraocular pressure (glaucoma)

Question 5

Icteric sclera

Answer 5

Yellow sclera

Question 6

Miotic response

Answer 6

Pupil 2 mm.

Question 7

Mydriatic response

Answer 7

pupil >6 mm

Question 8

Legally blind

Answer 8

Below 20/200

Question 9

What is a cataract and what are causes of it?

Answer 9

(1) The lens of the eye becomes cloudy.

(2) Drug reactions, injuries, and radiation. Senile cataracts are the most common type

Question 10

The sclera is covered by a thin transparent membrane known as the

Answer 10

Conjunctiva

Question 11

Rapid, uncontrolled movements of the eye that can occur in the vertical or horizontal direction. The etiology may be related to vestibular disease (central or peripheral), medications or other neurological processes

Answer 11

Nystagmus

Question 12

Clear dome over the iris

Answer 12

Cornea

Question 13

Others parts you can’t see are:

Answer 13

(1) The lens, which sits behind the pupil
(2) The retina, which is the inside of the back of the eye
(3) The optic nerve, which is at the back of the eye

Question 14

Light enters your eye through your

Answer 14

Cornea, then continues through the pupil and lens.

Question 15

What are the visible structures of the eye?

Answer 15

(1) The iris, which is the coloured part
(2) The cornea, which is the clear dome over the iris
(3) The pupil, which is the black hole in the centre of the iris
(4) The sclera, which is the white part
(5) The conjunctiva, which is a thin layer of tissue covering the front of your eye, except the cornea

Question 16

How the eye works to deliver an image to the brain

Answer 16

The cornea and lens focus the light onto the retina.

The retina is a layer of nerve tissue that includes:

Rods, which identify shapes and movement
cones, which detect detail and colours
Rods and cones absorb light signals, change them into nerve impulses, and send them to your brain via the optic nerve.

Your brain recognises the nerve impulses as a visual image.

Question 17

Miosis

Answer 17

Pupil appears small

Question 18

Ptosis

Answer 18

Droopy eye lid

Question 19

Anisocoria

Answer 19

Pupils are unequal in size

Question 20

Direct response

Answer 20

Normal pupil constricts when exposed to bright light

Question 21

Consensual response

Answer 21

Light presented to the opposite eye also causes constriction

Question 22

Fundoscopic examination with ophthalmoscope

Answer 22

Optic disc
Colour
Contour and sharpness of disc edges
Disc to cup ratio
Papilledema (increased intracranial pressure)
Vasculature
Colour
Size
Light reflex
Venous pulsations
Arteriovenous malformations
Fovea and surrounding macula (dry atrophic vs. wet exudative, drusen)
Retina
Colour
Cotton wool spots
Tears
Microhemorrhages