Question

Which if the following statements are true for presbyopia?
     A) Decreased power of accommodation
     B) Weak ciliary muscles and reduced flexibility of eye lens
     C) Usually occurs with increasing age
     D) All of the above

Answer 1

Hint: As people grow older, their eyes become weaker in the sense that the eye lens cannot focus on objects properly anymore and produce their image correctly on the retina. This condition is called presbyopia.

Complete step by step answer:
As a person ages, the person loses his or her power of accommodation in the eye. The power of accommodation is the ability of the lens of the eye to change its focal length to accommodate for different objects kept at different distances and change the focal length of the eye lens accordingly so that the image is formed on the retina properly. However, with age, the ciliary muscles, which are responsible for this power of accommodation and changing the focal length of the eye lens, become weak and the eye lens cannot focus as sharply as before.
The near point of the eye becomes greater and the far point of the eye becomes smaller than infinity. This combined condition of myopia and hyperopia is called presbyopia.

So, the correct answer is “Option D”.

Note: Students must note that presbyopia is corrected by using bifocal corrective lenses. Bifocal lenses consist of two parts, a convex lens and a concave lens on the bottom and the top of the total lens structure respectively. The convex lens helps in correcting and fixing near vision (hyperopia) while the concave lens helps in correcting distant vision (myopia).