ad with glasses or contacts before the operation — because of corneal haze or irregular tissue removal. Worse complications are very rare.

* Long-term complications?

Although the procedures are relatively new and the long-term risks unknown, many experts say there’s no reason to suspect any significant long-term complications.

Some, however, have raised concerns about lasers thinning the cornea, which already gets thinner as you age. This results in an increased risk of developing corneal ectasia or keratectasia (where the cornea bulges forward, distorting vision and causing short sight again), limiting the potential for laser surgery for corneal diseases in later li

While laser eye surgery isn’t particularly difficult technically, there are risks and side effects, as with any surgery. It’s not unusual to feel some discomfort and perhaps have blurry vision for the first few days. But there can be more serious problems:

* PRK and infection

PRK is a less complicated operation, so there’s less risk of surgical error. But there is a slightly greater chance of infection while healing (around one in 1000) than with LASIK. This may delay healing but usually doesn’t cause long-term problems.

* LASIK and damage to the corneal flap

With LASIK there is a slight risk — about one in 500 — that the corneal flap will be cut off or damaged. If the flap is put back in the correct position, there should be no adverse effects. But if the flap is lost, this will lead to long-sightedness and irregular scarring of the remaining corneal bed, leading to haze and blur.

* Undercorrection

In around one out of 15 cases, the surgery results in undercorrected vision and the operation has to be redone. Find out beforehand whether your payment includes further treatment in such a situation.

* Problems with night vision

Some patients end up with 20/20 vision but have irritating or distressing side effects, the most common being night vision problems: estimates range from around 4% to 30% of patients, depending on the time since surgery and how much of a problem the symptoms cause (from being a regular annoyance to only just noticeable).

Almost all patients have some symptoms in the first couple of weeks, but their severity diminishes over time. The effects can be particularly problematic when driving, when there’s a loss of contrast sensitivity and headlights appear much bigger, are blurry or have halos around them. For this reason, most county and city police forces in England and Wales won’t employ anyone who’s had laser eye surgery.

Around 1% of people are permanently affected and can’t drive at night as a result of these side effects.

Your surgeon should check your pupil size in darkness before the operation: if it’s more than 7 mm you’re more likely to have night vision problems and should reconsider having the surgery. But a pupil size smaller than 7 mm is no guarantee you won’t suffer these problems. Poor night vision can sometimes be corrected with eyedrops that reduce pupil size (for example, Pilocarpine, which contracts the pupils), or by wearing contact lenses at night. With newer laser treatments and improved techniques, these side effects are becoming less common.

* Worse than before?

A small proportion of people (around one to three per thousand) end up with poorer ‘best-corrected’ vision — that is, worse vision than they had with glasses or contacts before the operation — because of corneal haze or irregular tissue removal. Worse complications are very rare.

* Long-term complications?

Although the procedures are relatively new and the long-term risks unknown, many experts say there’s no reason to suspect any significant long-term complications.

Some, however, have raised concerns about lasers thinning the cornea, which already gets thinner as you age. This results in an increased risk of developing corneal ectasia or keratectasia (where the cornea bulges forward, distorting vision and causing short sight again), limiting the potential for laser surgery for corneal diseases in later lif

maged. If the flap is put back in the correct position, there should be no adverse effects. But if the flap is lost, this will lead to long-sightedness and irregular scarring of the remaining corneal bed, leading to haze and blur.

* Undercorrection

In around one out of 15 cases, the surgery results in undercorrected vision and the operation has to be redone. Find out beforehand whether your payment includes further treatment in such a situation.

* Problems with night vision

Some patients end up with 20/20 vision but have irritating or distressing side effects, the most common being night vision problems: estimates range from around 4% to 30% of patients, depending on the time since surgery and how much of a problem the symptoms cause (from being a regular annoyance to only just noticeable).

Almost all patients have some symptoms in the first couple of weeks, but their severity diminishes over time. The effects can be particularly problematic when driving, when there’s a loss of contrast sensitivity and headlights appear much bigger, are blurry or have halos around them. For this reason, most county and city police forces in England and Wales won’t employ anyone who’s had laser eye surgery.

Around 1% of people are permanently affected and can’t drive at night as a result of these side effects.

Your surgeon should check your pupil size in darkness before the operation: if it’s more than 7 mm you’re more likely to have night vision problems and should reconsider having the surgery. But a pupil size smaller than 7 mm is no guarantee you won’t suffer these problems. Poor night vision can sometimes be corrected with eyedrops that reduce pupil size (for example, Pilocarpine, which contracts the pupils), or by wearing contact lenses at night. With newer laser treatments and improved techniques, these side effects are becoming less common.

* Worse than before?

A small proportion of people (around one to three per thousand) end up with poorer ‘best-corrected’ vision — that is, worse vision than they had with glasses or contacts before the operation — because of corneal haze or irregular tissue removal. Worse complications are very rare.

* Long-term complications?

Although the procedures are relatively new and the long-term risks unknown, many experts say there’s no reason to suspect any significant long-term complications.

Some, however, have raised concerns about lasers thinning the cornea, which already gets thinner as you age. This results in an increased risk of developing corneal ectasia or keratectasia (where the cornea bulges forward, distorting vision and causing short sight again), limiting the potential for laser surgery for corneal diseases in later li

pending on the time since surgery and how much of a problem the symptoms cause (from being a regular annoyance to only just noticeable).

Almost all patients have some symptoms in the first couple of weeks, but their severity diminishes over time. The effects can be particularly problematic when driving, when there’s a loss of contrast sensitivity and headlights appear much bigger, are blurry or have halos around them. For this reason, most county and city police forces in England and Wales won’t employ anyone who’s had laser eye surgery.

Around 1% of people are permanently affected and can’t drive at night as a result of these side effects.

Your surgeon should check your pupil size in darkness before the operation: if it’s more than 7 mm you’re more likely to have night vision problems and should reconsider having the surgery. But a pupil size smaller than 7 mm is no guarantee you won’t suffer these problems. Poor night vision can sometimes be corrected with eyedrops that reduce pupil size (for example, Pilocarpine, which contracts the pupils), or by wearing contact lenses at night. With newer laser treatments and improved techniques, these side effects are becoming less common.

* Worse than before?

A small proportion of people (around one to three per thousand) end up with poorer ‘best-corrected’ vision — that is, worse vision than they had with glasses or contacts before the operation — because of corneal haze or irregular tissue removal. Worse complications are very rare.

* Long-term complications?

Although the procedures are relatively new and the long-term risks unknown, many experts say there’s no reason to suspect any significant long-term complications.

Some, however, have raised concerns about lasers thinning the cornea, which already gets thinner as you age. This results in an increased risk of developing corneal ectasia or keratectasia (where the cornea bulges forward, distorting vision and causing short sight again), limiting the potential for laser surgery for corneal diseases in later li

pupil size in darkness before the operation: if it’s more than 7 mm you’re more likely to have night vision problems and should reconsider having the surgery. But a pupil size smaller than 7 mm is no guarantee you won’t suffer these problems. Poor night vision can sometimes be corrected with eyedrops that reduce pupil size (for example, Pilocarpine, which contracts the pupils), or by wearing contact lenses at night. With newer laser treatments and improved techniques, these side effects are becoming less common.

* Worse than before?

A small proportion of people (around one to three per thousand) end up with poorer ‘best-corrected’ vision — that is, worse vision than they had with glasses or contacts before the operation — because of corneal haze or irregular tissue removal. Worse complications are very rare.

* Long-term complications?

Although the procedures are relatively new and the long-term risks unknown, many experts say there’s no reason to suspect any significant long-term complications.

Some, however, have raised concerns about lasers thinning the cornea, which already gets thinner as you age. This results in an increased risk of developing corneal ectasia or keratectasia (where the cornea bulges forward, distorting vision and causing short sight again), limiting the potential for laser surgery for corneal diseases in later li

ad with glasses or contacts before the operation — because of corneal haze or irregular tissue removal. Worse complications are very rare.

* Long-term complications?

Although the procedures are relatively new and the long-term risks unknown, many experts say there’s no reason to suspect any significant long-term complications.

Some, however, have raised concerns about lasers thinning the cornea, which already gets thinner as you age. This results in an increased risk of developing corneal ectasia or keratectasia (where the cornea bulges forward, distorting vision and causing short sight again), limiting the potential for laser surgery for corneal diseases in later life and increasing susceptibility to corneal rupture.

Laser surgery is a rapidly evolving field of knowledge and expertise, and continual refinements based on improved technology and findings from scientific studies are likely to reduce the risk of minor side effects as well as more major damage.