refraction

Question 1

what is short sighted

Answer 1

myopia

Question 2

what is the eyeball in myopia

Answer 2

too long- only close objects focus on the retina

Question 3

causes myopia

Answer 3

genetic

Question 4

does myopia worsen with age

Answer 4

yes

Question 5

average age of a child to start becoming myopic

Answer 5

6 years

Question 6

what is pathological myopia

Answer 6

myopia progresses above 6 dioptres- secondary degen of vitreous and retina- retinal detachment, macular bleeding

Question 7

how to correct myopia

Answer 7

concave lens

Question 8

what is astigmatism

Answer 8

if cornea or lens don’t have the same degree of curvature in the horizontal and vertical planes so image of objects is distorted

Question 9

what is long sighted

Answer 9

hypermetropia

Question 10

what is the eyeball in hypermetropia

Answer 10

too short

Question 11

how to correct hypermetropia

Answer 11

convex lens

Question 12

what is presbyopia

Answer 12

ciliary muscle reduces tension in the lens allowing it to get more convex for close focusing. with age the lens stiffens hence the need for glasses for reading