Refractive surgery is safer than wearing contact lenses, according to a US professor of ophthalmology writing in the October edition of the Archives of Ophthalmology.
In a letter, Professor William Mathers from Oregon Health & Science University, reviewed several large-scale studies and concluded that the chance of suffering vision loss is greater for contact lens wearers than patients of refractive surgery.
Citing a study published in The Lancet in 1999, Mathers reported the rate of bacterial keratitis to be 3.5 cases per 10,000 persons per year for daily wear contact lenses and 20 cases per 10,000 persons per year for extended-wear contact lenses.
Over a 30-year period he said that the risk of bacterial keratitis rose to one case per 100 persons for daily wear lenses. Referring to published data he added that the incidence varied by country from an average of 0.3 to 1.5 cases per 10,000 persons per year with the highest rate in Scotland.
Mathers claimed that assessing the risk of vision loss from refractive surgery can be calculated more directly and reported an average infection rate of one case per 800 persons with 25 per cent of infected eyes experiencing moderate vision loss.
Citing his own data from the Casey Eye Institute, Portland, he proposed that the incidence of vision loss after refractive surgery greater than two lines may be one case per 10,000 persons.
Mathers concluded that complications from contact lenses accumulate over years, whereas from surgery they may occur over a brief time, the data 'strongly suggests that further investigation into the risks is needed'.