Having "twenty-twenty" (20/20) sight is what lots of those think as the perfect vision.

For the all the curious people out there, what exactly does having 20/20 sight signify? And will laser eye treatment provide me this result?

This is a conventional measurement of optical acuity (or how well you see in the distance). The beginning 20 from the 20/20 vision is the measurement (in feet) of the testing distance because the letter chart is normally 20ft away while the following 20 is how faraway the "normal" person can perceive that size letter at. This means that a person who sees the "20" (2nd 20) sized letter at 20 feet has a sight of 20/20.

A sight of 20/40 simply means that the testing distance is 20 feet and for the letter size of 40, while a "normal" person can see this at 40 feet, double the testing distance. However, you can merely make out from 20 feet away, so 20/40 is not quite as good as 20/20.

Despite this, you can still pass your usual driving license exam in terms of optical acuity because the standard is 20/40 or better, with both eyes open. A stricter standard is necessary for commercial or heavy vehicles though, as the visual acuity demands a vision of 20/40 with both eyes open. Should spectacles be required just to fulfill this criteria, then they should always be worn when driving.

For commercial pilots, among other things, a optic acuity of 20/20 is required.

Note that for metric units, 20/20 is identical to 6/6. That is, the testing distance is 6 meters.

Success with laser eye treatment for most folks means having 20/20 sight after the process. According to the recent studies conducted by Wagoner, M.D. et al, approximately 94% of individuals obtain 20/20 vision or better after refractive operation and virtually 100% of those can see the 20/30 line of letters. This means that the large majority of people can carefully drive without glasses after surgery.

Additionally, it means that having a 20/20 vision before the surgery would result to having that same visual acuity by means of eyeglasses after laser eye surgery. This is generally brought about by either an under correction or over correction which leaves patients with a residual prescription. if the expectations are not met during the initial operation, a second treatment can also be performed to improve the sight.

Other factors should also be considered when evaluating the success of refractive operation. Experiencing night time haloes around lights, dry eyes, and other optical anomalies are reasons for dissatisfaction, especially if they turn out to be long-term, chronic issues. The quality of life and patient satisfaction have been assessed with recent studies showing a contentment (not success) rate of 95% for current laser eye techniques**.

In essence, there are a lot of satisfied folks when it comes to the results of laser eye treatment. The options should always be weighed first and the risks understood. There are risks and there are benefits, but if the benefits outweigh the risk, then refractive surgery is for you.