Which one is better - Glasses or contact lenses?

Eye sight problems are common among most of the people such as nearsightedness, farsightedness, astigmatism or Presbyopia. We need to wear or use glasses or contact lenses to ease vision related problems.
Contact lenses are now quite popular, worn by approximately 30 million people in the USA alone.

The choice between eyeglasses and contact lenses depends on what sight problem you have, and the degree of the disorder. There are contact lenses to correct nearly every kind of vision problem, including astigmatism and presbyopia. Even if you enjoy wearing eyeglasses, contact lenses can be worn on a part time basis to suit your needs. Contacts are especially a good choice for sports, working out at the gym, and other leisure activities.                                                                          

Contact lenses offer many advantages over eyeglasses:

Distortion: In glasses the lenses vary in thickness, depending on the weakness of vision. The shape of an eyeglass lens creates distortion and the thicker the glass, the greater the distortion. The eye, looking through the center and then suddenly switching to the edge, sees the object being looked at move. This is called the "prism effect". If you look through a prism you can see how a straight line becomes bent. Even though the prism effect is gradual as the eye moves across the glasses lens and does not disturb the wearer very much, it can be a nuisance. This distortion can also affect stereoscopic vision until the brain has had time to compensate.
Contact lenses can also have this effect, but to a lesser degree. For anyone needing high powered correction, wearing contact lenses should be a real advantage.

Lens Strength:
Because of its closeness to the pupil, the contact lens often does not need to be as strong as glasses. The image formed at the back of the eye for the near-sighted is larger and less dazzling than with glasses-an effect which makes many near-sighted people who wear glasses choose lenses weaker than their full prescription, so they many not see well. For far-sighted people the image is smaller than with glasses. The power needed for contact lenses can be greater than for glasses. However, when far sight is fully corrected by contact lenses close work is easier than with glasses because the wearer does not have to accommodate so much.
Eye Problems: Some eye disorders can only be treated by contact lenses. These are: extreme far and near sight, unequal vision and astigmatism. People with keratoconus (a cone shaped cornea) or who have had a cataract operation are often better off with a contact lens.
Cosmetic Effect: This is the major reason for many people trying contact lenses. Either they feel glasses don’t look good, or they find them heavy and uncomfortable. The freedom of contact lenses is worth the effort involved in getting used to them.
Comfort:
To start with, wearing contact lenses is certainly more uncomfortable than glasses. In the long term, provided you can learn to adapt, you don’t notice you’re wearing them. Glasses, on the other hand, may be heavy on the bridge of the nose, steamy or sticky in wet or hot weather. There are, however, some common eye conditions that make wearing contact lenses impossible:
Dry Eyes: If your tear glands don’t make enough tears your eyes will become gritty and sore. The discomfort is relieved with eyedrops and by avoiding a dry or rapidly ventilated atmosphere. But contact lenses would irritate the soreness and so are unsuitable.
Wet Eyes: Too many tears can interfere with your vision. Watering eyes may be due to a cold, a foreign body or crying. But if your eyes are continually watery, this may be due to a blockage in the drainage channels and until it has been put right, it will not be possible to wear contact lenses.

Adapting To Lenses: It takes some perserverance to get used to lenses and a lot of people give up in the first two or three weeks. Motivation is of course, all important.
Expense: The cost of contact lenses are generally higher than a pair of eye glasses, when factoring in the cost of saline and cleaning solutions, lens cases, etc. This is especially true if you are using disposable contacts, some of which are designed to be thrown away every month, week, or day.
Much depends on where you live, and whether free health care is available. Some insurance plans will not pay for contact lenses, as they are considered cosmetic and not essential.

With the comfort and ease of contact lenses today, there is nothing wrong with wearing contacts part time and glasses the rest of the time.

Note: Even if you wear contact lenses full time, you should have an up-to-date pair of eyeglasses handy to wear when you are not wearing your contact lenses. For the greatest safety and comfort, you should remove your contact lenses at least one hour before sleep. You should also remove your contact lenses and wear eyeglasses if your eyes feel dry or become uncomfortable for any reason. If the discomfort persists, see your eye doctor immediately.

Useful links:

* ‘Eye Topics’
* ‘All about contact lenses’
* ‘Eyes and vision’
* Wouldn’t You Rather Wear Contacts Than Glasses?
**** Article first published at 'Factoidz'

You may like to read: How to Keep Your Eyes Safe and Healthy Using Contact Lenses?