what are the advantages and diadvantages of contact lenses from the medical view??

Question

I want scientific information..please

Answer 1

Adv--increases field of vision,no botheration about spects.

Disadv-- 1.May cause injury to cornea.
2. May impair oxygen supply to cornea.
3.May be asource of infection to cornea.
4.Can't be used continuously.

Answer 2

Actually glasses often provide better optics than contact lenses but the difference is so minimal that most people aren't bothered.
Sitting closer to the eye only helps in having clearer peripheral vision but does not improve vision. Since it does sit closer, you have to vertex the difference of that ~13mm which changes the power of the prescription.
They do not stimulate the ciliary muscle or help with blood supply. The cornea is avascular and the recieves oxygen from the tear film. The contact lens decreases this oxygen supply which can lead to blood vessels growing into the avascular cornea. These blood vessels are weak and can easily leak.
Contact lenses can be beneficial if the differences in the power of your eyes is significant enough to cause different image sizes (only if the refractive error is refractive and not axial)
Contact lenses can be used cosmetically to correct problems with a mishapen iris. This can also limit excess light getting to the retina. In albinism, where the iris is too light and the eyes are extremely sensitive to light, a colored contact lens can help limit the light entering the eye, providing relief.

Answer 3

sukhwinder b has answered this perfectly.
So let me just ask you this, have you ever come across an optometrist who wears contact lens on a regular basis?
(not me). . .

I think the disadvantages are far more than the advantages.
If you are considering contact lenses I am strongly against it.
I used to wear contact lenses, I was VERY VERY careful, and still after a few years I started to become allergic to the contact lens solution. . . and got gritty, itchy eyes. I was told it wouldn't go away, but thank goodness it did after about a years use of artificial tears.

Answer 4

scientifically advantages are that:
They help in better focus of the image on the retinal screen of the eye,which conventional specs only do optimally.
It sits closer to the natural eye lens and hence helps in improvement of vision faster,but it takes time.This is only compared to conventional lens.
Helps somewhat in preventing dark circles,thats because the lens acts as a stimulant to the ciliary muscles and hence inundates te area with better blood supply.
and..............................................
You dont hassle around too much with those harry potter like goggles!

Disadvantages:
the wearer has to exercise extreme caution in proper storage and sanitisation of the lens prior to usage everytime.
More and more people have inflammation of the cornea at some point.
NEVER rub your eye,have constant presence of mind that you have put a piece of glass in yr eye!
Basically,conjuctivitis is the only serious issue you have to deal with,if not careful with hygiene of the contacts.

However,latest tech has produced various types of contacts made out of several synthetic materials,check out which one will be compatible to you according your usage.
Best is discuss Contacts safety standards with yr optician.

Answer 5

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