New techniques in laser eye surgery could eliminate night vision problems and other undesirable side-effects of the treatment, enabling thousands more people to put aside their glasses and contact lenses.

The latest high-speed, high-precision lasers and iris recognition technology can provide customised procedures to replace the previous “one treatment fits all” approach, resulting in an operation that produces 20/20 vision or better, ophthalmologists say.

The innovations improve the popular LASIK (Laser in Situ Keratomileusis) method of eye surgery, which is used to correct sight and astigmatism – problems resulting from an irregular-shaped cornea.

While this treatment can correct mild sight impairments for the majority of patients, those with more severe problems or natural fluctuations in the shape and thickness of the cornea can be considered ineligible for surgery because of the risk of complications. Problems from unsuccessful surgery or postoperative issues include painful dry eyes, blurred vision and bursts of blinding light or “halos” at night.

But by scanning and measuring the eye carefully before taking aim with a laser, surgeons are now able to assess the likely results of treatment and select the right procedure from a number of options.

The latest system, known as Zyoptix, is manufactured by the US optics firm Bausch & Lomb. In trials involving 40 patients with short-sightedness, 96 per cent of those treated with Zyoptix had their sight restored to at least 20/20 or 6/6 vision within six months, while 89 per cent achieved even better – 6/5, described as “fighter pilot vision” by experts.

Sheraz Daya, an eye surgeon at the Centre for Sight in East Grinstead, West Sussex, who conducted the trial, said that the results were much more impressive than those achieved with the commonly available Planoscan laser, also made by Bausch & Lomb.

Sight was restored to near-perfect levels as soon as a month after treatment, in the Zyoptix group, he said, adding: “Patients could read more lines on a chart, and in higher definition, very quickly after the operation. This compares with previous methods, where vision usually deteriorates after the procedure and only gradually returns to normal, by about six months,” he said.

Dr Daya said that the new technology, also available at Moorfields Eye Hospital in London, had increased the number of patients he was able to treat by 25 per cent.

“Laser surgery used to be performed with standard technology that treats only the prescription of the eyes,” he said. “Patients who had night vision problems, very high or complicated prescriptions, thin corneas or large pupils were simply not suitable. But with Zyoptix, many more of these patients can now be treated.”

Before surgery, the iris image of each patient’s eye is captured on software. Iris recognition technology, related to that used in airport security, can then be used to build up a personal map of the fine optical aberrations that might affect the outcome of surgery.

The procedure allows options to remove less tissue, eliminate night vision problems (known as Waterfront surgery) and, most importantly, unlike every other laser treatment optio, to leave the natural shape of the cornea (aspheric surgery). Since the start of the year, Dr Daya has treated nearly 200 people with these three main options which, although more expensive, produce better outcomes than the traditional Planoscan treatments.

“The patient is sitting when this assessment is made,” Dr Daya said. “During the operation, though, the patient is lying down. This makes the eye rotate slightly and could marginally affect the result. Iris recognition allows us to compensate for this rotation. As the eye moves, the iris image moves and only when it is superim posed over the patient’s iris, do we fire the laser.”

The surgery is also more comfortable: the surgeon fires the laser for about 20 seconds, compared with one minute when using older techniques.

Laurence Benjamin, of the Royal College of Ophthalmologists, described the new scanning techniques as exciting, but added that it needed to be tested on a greater number of patients. “The procedure has been in clinical trials for about a year but if it lives up to its promise we could see many patients benefiting from it within a year or two,” he said.

Dr Daya added: “The quest for perfect vision is almost over.”

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