Which of the following statements for persons suffering from presbyopia is/are correct?
1. They cannot distinguish colours.
2. It usually develops with ageing.
3. They wear either bi-focal lenses consisting of both concave and convex lenses or progressive lenses.
Select the answer using the code given below :
Presbyopia: Understanding the Condition
Presbyopia is a common age-related vision condition where the lens of the eye gradually loses its flexibility. This makes it difficult for the eye to focus on close-up objects.
Statement Analysis for Presbyopia
Let's examine each statement provided regarding individuals with presbyopia:
Statement 1: Colour Vision Impairment
- Presbyopia primarily affects the eye's ability to change focus from distant objects to near objects. This is due to the hardening of the lens and weakening of the ciliary muscles over time.
- It does not typically affect the eye's ability to distinguish between different colours. Issues with colour vision are usually related to the cone cells in the retina or the optic nerve, not the lens's focusing ability.
- Therefore, the statement "They cannot distinguish colours" is incorrect.
Statement 2: Development with Ageing
- Presbyopia is a natural part of the ageing process. It typically begins to affect people around the age of 40 and progresses over time.
- The lens inside the eye becomes less flexible, hindering the ability to focus on nearby items, like reading a book or a phone screen.
- Therefore, the statement "It usually develops with ageing" is correct.
Statement 3: Use of Bi-focal or Progressive Lenses
- To correct the vision impairment caused by presbyopia, specialized lenses are often prescribed.
- Bi-focal lenses have two distinct optical corrections in one lens – one for clear distance vision and another for clear near vision. This near-vision segment often incorporates convex (plus power) lenses to aid close focusing.
- Progressive lenses offer a seamless transition between different prescription powers, providing clear vision at all distances (far, intermediate, and near) without visible lines.
- While the description mentions "both concave and convex lenses," bi-focal or progressive lenses are indeed the standard corrective eyewear for managing presbyopia, helping individuals regain clear near vision. The combination mentioned might apply if the person also has other refractive errors like myopia (nearsightedness, corrected by concave lenses) alongside presbyopia.
- Therefore, the statement "They wear either bi-focal lenses consisting of both concave and convex lenses or progressive lenses" is considered correct in the context of common treatments for presbyopia.
Conclusion on Presbyopia Statements
Based on the analysis:
- Statement 1 is incorrect.
- Statement 2 is correct.
- Statement 3 is correct.
Thus, the correct statements regarding persons suffering from presbyopia are 2 and 3.
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