One of the world’s largest studies into using laser treatment to prevent vision loss among people at risk of developing a severe form of glaucoma has cast new light on treating the disease.
The study of almost 900 Chinese patients, led by Professor Mingguang He from the Centre for Eye Research Australia and University of Melbourne, has been published in The Lancet. It finds laser peripheral iridotomy treatment – which is commonly used around the world as a preventative measure for people at risk of developing primary angle closure glaucoma – has only modest benefits.
A change in practice from routine preventative laser could save considerable time, money and unnecessary medical interventions
It recommends against the widespread treatment of all people at risk of developing the condition as a public health measure.
Additionally, it says there should instead be a focus on providing more intensive treatment to those most at risk of losing their sight, and on detecting glaucoma earlier.
The study tracked a group of patients aged 50 to 70 at an eye clinic in Guangzhou, China, over six years.
Patients received laser treatment in one randomly selected eye while the other was left untreated. Researchers then monitored both eyes over six years to determine the impact the treatment had on preventing further development of the disease.
Final results showed that although there was a small, statistically significant improvement in eyes that were treated – overall the benefits were limited, and the vast majority of patients did not develop any glaucoma symptoms in their untreated eye.
Professor He says the findings have major public health implications for China, where 28 million people are at risk of primary angle closure glaucoma.
“In the past these patients could have been considered eligible candidates for laser treatment, but this new evidence shows that many do not need treatment,” he says.
About three quarters of the world’s 20 million primary angle closure glaucoma cases occur in Asia.
Professor He says despite preventative laser treatment being used worldwide since the 1970s to prevent primary angle closure glaucoma, until now there had been little evidence about its long-term effectiveness in preventing the development of glaucoma.
“Given our results, widespread use of preventative laser treatment is not the best use of health care resources, which could instead by redirected to providing more intensive treatment to those most at risk of blindness and to identifying glaucoma earlier,” said Professor He.
“A change in practice from routine preventative laser could save considerable time, money and unnecessary medical interventions.’’
Professor He’s study was carried out in partnership with Zhongshan Ophthalmic Centre, Sun Yat-Sen University, China; the National Institute for Health Research and Biomedical Research Centre, Moorfields Eye Health Hospital, London; UCL Institute of Ophthalmology, London; Dana Centre for Preventative Ophthalmology, Wilmer Eye Institute and Department of International Health, Johns Hopkins School Bloomberg School of Public Health, US and National University of Singapore.