Final answer:
The correct statement is that cataract surgeries are done to remove clouded lenses from the eyes. They are minimally invasive and can be performed on patients of any age, not only those above 70. The procedure carries some risk, and post-surgery, some patients might still need reading glasses.
Step-by-step explanation:
Among the given statements about cataract surgeries, the correct one is that cataract surgeries are performed to remove clouded lenses from the eyes. Cataract surgeries involve the removal of the eye's natural lens once it has become opaque and its replacement with an artificial intraocular lens. This is necessary because a cataract is cloudiness in the lens of the eye that causes light to be dispersed or diffused, leading to impaired vision.
Cataract surgeries are not non-invasive; they are minimally invasive procedures. Small incisions made in the eye allow for the removal of the clouded lens and the insertion of the intraocular lens. It is incorrect to say that cataract surgeries have no risks or side effects; like any surgery, there are potential risks, such as infection, bleeding, or retinal detachment, though these are relatively rare. Moreover, cataracts can affect individuals at any age, although they are most commonly found in older adults. Therefore, cataract surgeries can be performed on patients of any age, not only those above the age of 70.
After the surgery, some patients may find they have perfect distant vision but could still require reading glasses, depending on the type of intraocular lens implanted and the pre-existing vision conditions. For example, if a person was nearsighted (myopic) before surgery, the power of the intraocular lens would be less than the power of the removed clouded lens to correct the vision. It should also be mentioned that repeated exposure to UV-B rays can lead to the formation of cataracts, indicating the importance of protective eyewear to reduce this risk.