Focus on vision loss

Professor Roger Truscott
21 February 2007

Vision is the most valued of our five senses. A large part of our brain is devoted to processing the visual information that is transmitted to the brain from our retina. It is a miraculous system but, with age, our eyes deteriorate. By age 50 nearly everyone needs reading glasses for close work such as reading or sewing.

Why? It turns out that the reason for this universal phenomenon can be traced back to the lens of the eye. Put simply, it becomes too hard! In fact it becomes one thousand fold stiffer during our lifetime! This inability to focus up close is called presbyopia. In young people the lens is soft and pliable and it can change shape therefore allowing us to focus very close.
In middle-aged people, no matter how hard the eye muscles work to try to change the shape of the lens, it is just too hard. Professor Truscott's team team discovered the underlying reason for presbyopia in 2004. He moved from the University of Wollongong (UOW), to the University of Sydney in 2005 and now works at the Save Sight Institute at the Sydney Eye Hospital. "The environment there is excellent, and the University of Sydney is very supportive of medical research."

Earlier, his team had explained the reason for cataracts which are a leading cause of world blindness. In this very common condition of the elderly, the lens becomes cloudy and eventually impairs the transmission of light through to the retina. At present the only method available for treating cataract is surgery. The cloudy lens is replaced by a clear plastic one. This is the most common surgical procedure in Western countries and is a major cost to the health system.

"We found evidence that nuclear cataract results from the development of a barrier in the lens at middle age. This barrier impedes antioxidants from reaching the lens centre and therefore leaves this region exposed to oxidative damage. My aim is to find a non-surgical treatment to prevent cataract, possibly by using diet or eye drops. To do that we need to understand precisely what happens to the lens before cataract develops, for example, why the barrier forms."

"Currently we are exploring if there is a link between presbyopia - which happens in the 40-50 year age group - and cataract, which typically appears a decade or two later."

Professor Truscott was recently awarded the Cataract Research Award from the National Foundation for Eye Research in the United States. 'This is recognition of the outstanding research effort of all the people in my group, and my collaborators in both Sydney and Wollongong. It is a great honour. I am the first Australian to be awarded the prize."

Professor Roger Truscott is a National Health and Medical Research (NHMRC), Senior Research Fellow - one of an elite band of medical researchers in Australia whose salary is provided by the NHMRC. His research is currently funded by the National Institutes of Health (USA) and the Australian Research Council.