The gel technique, which involves replacing the contents of the lens in the eye with a soft polymer, will initially be used to improve cataract surgery in elderly patients.
“But once it is shown to be safe and effective, we think that more and more younger people who are starting to need reading glasses will adopt it as well,” Arthur Ho, of the University of New South Wales, told New Scientist magazine on Wednesday.
As people age, the lens in the eye, which focuses by changing shape, becomes less flexible so by the time most people reach their mid-to-late 40s they need reading glasses.
Ho, who is a member of the Australian government’s multinational Vision Co-operative Research Centre, believes he and his team have discovered the right gel formulation for human eyes and hope to begin trials next year.
Inserting the gel would be similar to cataract surgery but the lens would not be replaced. The contents will be sucked out by a tiny incision in the cornea and replaced with the gel.
“This could be a quick 15-minute procedure,” Ho added.
The Australian scientific team believe that if successful in human trials – due to begin in 2004 – the technique will also overcome cataracts as a cause of loss of sight.
Tests on animals found that the team’s gel lens has around four times the focal power of a pair of reading glasses – significantly better than the researchers’ had aimed for.
“However we have yet to test it in human patients, so we won’t know for sure till then,” Ho concluded.
The team also wanted to combine the ability to focus close-up with other forms of vision correction, such as distance refractive error – to provide total correct vision, short and long, for the ageing eye.
Besides inserting the soft gel lens, they also propose to insert a novel ‘mini-lens’ to correct other aspects of vision.
This ‘mini-lens’ will be embedded in the gel within the human lens itself, giving both distance and close-up vision and, potentially, good vision at all distances that will last many years – maybe even a lifetime.