Visual system (pt 2) NOT FINISHED

Question 1

What are the 2 types of lens?

Answer 1

Converging lens (convex) - Light rays in

Diverging lens (concave)- Light rays out

Question 2

What is emmetropia?

Answer 2

When Light falls onto the retina correctly

Question 3

What is ametropia?

Answer 3

Refractive error, when light rays don’t fall on the retina

Question 4

What are some examples of ametropia?

Answer 4

-Myopia
-Hyperopia
-Astigmatism
-Presbyopia

Question 5

What is myopia?

Answer 5

When light rays converge anterior to the retina

Question 6

Symptoms of myopia?

Answer 6

-Blurred distance vision
-Squinting to improve uncorrected visual acuity
-Headache

Question 7

How to treat myopia?

Answer 7

Correction with:
-Diverging lens
-Contact lens
-Removing lens to reduce refractive power of the eye

Question 8

What is hyperopia?

Answer 8

Light focuses behind the retina

Question 9

What are the physiological causes of hyperopia?

Answer 9

insufficient refracting power

Question 10

Symptoms of hyperopia

Answer 10

visual acuity near/close tends to blur

Question 11

What is astigmatism?

Answer 11

Where light rays focus in two points rather than one

Question 12

What is presbyopia?

Answer 12

Naturally occurring loss of accommodation (focus on near objects).