Contrast sensitivity is also a major concern for PRK patients. Researchers at Moorfield’s Eye Hospital in London reported that 30 per cent of its PRK patients suffered a loss of contrast sensitivity within two years of surgery (Refractive Surgery Symposium, London 2001) - and the same symposium heard that half of all LASIK patients suffered a similar loss, one year after surgery.

The LASIK technique can cause the cornea to weaken in up to 40 per cent of all cases (Lancet, 2003; 361: 1225-6) and, sometimes, the weakened cornea resumes its original shape - so the myopia returns.

One study reported on a variety of complications following LASIK surgery. Of the 24 cases, 13 of the complications occurred during the procedure, and the rest afterwards. The technique, the researchers concluded, could result in serious complications that can lead to visual loss (Eur J Ophthalmol, 2003; 13: 139-45).

Patients may also have to go through a second, corrective operation. In one study of 1306 LASIK patients, over 10 per cent had to have a second operation, a likelihood that increases with age, the degree of initial correction and the extent of astigmatism (Ophthalmology, 2003; 110: 748-54).

As with PRK, postoperative infection is also a concern for the LASIK patient. One study found that keratitis could occur up to 450 days after surgery, and was serious enough to threaten vision (Ophthalmology, 2003; 110: 503-10).

The US Food and Drug Administration (FDA) is equally unsure of the LASIK technique. According to its website (www. fda.gov), LASIK is 'an option for risk takers'.

LASEK is a newer technique, so there are fewer studies into its efficacy and safety. However, one study from Japan urges caution. After studying the progress of 42 LASEK patients, the researchers reported postoperative complications such as pain, delayed recovery of visual sharpness and corneal haze (Nippon Ganka Gakkai Zasshi, 2003; 107: 249-56).

Compared with PRK, LASEK may result in less discomfort in the early postoperative period, faster visual recovery and less haze, but these claims, made by LASEK proponents, need to be vindicated in long-term trials, say researchers at the University of Washington (Semin Ophthalmol, 2003; 18: 2-10).

With more and more ‘walk-in’ laser-surgery centers opening up, the emphasis is on the benefits; very few mention the possible risks either in their advertisements or during the face-to-face consultations before the operation.

Some patients whose lives have been ruined by eye surgery have taken on the task of providing a health warning to potential patients, and also provide help to those already affected. The Surgical Eyes Foundation (website: www.surgicaleyes.org) is a US-based support group for people with 'longer-term complications from refractive surgery'. Their aim is 'to restore quality of life to the thousands who suffer from complications of . . . refractive surgeries'.

Unrealistic expectations, or perhaps expectations that have been put in the patient’s mind by advertisements or during the preoperative discussions, could be at the heart of the issue. Even if you are among those who suffer no reactions or complications after surgery, you are still likely to need to wear glasses for some tasks, eye surgeon David Gartry told the BBC News (26 May 2003).

Quality of treatment can vary enormously from one clinic to another. Yet this information is rarely, if ever, made available to patients choosing where to have their treatment.