3rd June 2011
Inaugural lecture by James Wolffsohn, Professor of Optometry at Aston University
Perfect sight, without glasses or contact lenses, right into old age is a realistic dream, according to James Wolffsohn, Professor of Optometry at Aston University.
In his recent lecture, entitled The Demise of Spectacles- Restoring Youthful Vision with Bionic Implants, he focused on historical, current and future technological solutions for improving the vision of our nation.
During the course of the presentation Professor Wolffsohn posed a number of questions on historical and current research and his aims for the future health of our eyes with the potential for ‘bionic’ implants. These are extra flexible ‘super lenses’ which could correct both long and short sightedness, as well as restoring eye focus allowing patients to throw away their glasses for good. These flexible lenses are inserted into the eye itself in a simple operation that replaces the existing lens in a similar way to the standard operation for cataracts. These lenses can be squeezed by the eye’s muscles into the shapes needed to focus on both near and distant objects, and all points in between.
He started with this: Why do only some younger people need glasses? Why do our eyes deteriorate as we get older, particularly in old age.
“We all vary in physical size, mainly due to a combination of our genetics and nutritional intake. In a similar way, the development of the eye is strongly linked to our genetic composition, though visual stimulus also plays a large part,” explained Professor Wolffsohn. He added: “At birth our eyes are only at approximately 70% of adult size, then through the process known as Emmetropization the eyes endeavour to grow to the correct proportions so that its length matches its optical power. However it is common for the eye to overshoot the correct size and expand beyond the needed dimensions, which leads to short-sightedness.”
“However even those with perfectly developed eyes will begin to develop visual difficulties as they age. This is because the lens within our eye, which provides our ability to focus on objects at different distances, harden over time, preventing the normal shape change in response to contraction of the ocular muscles. Starting from a very young age we gradually lose the ability to focus and you have to hold something further away to read it. By around 45 years you can no longer stretch your arms far enough and you need glasses for near tasks.”
What are the options for correcting vision?
“Following the loss of eye focus, vision at a range of distances can be achieved by: looking through a different portion of spectacles (bifocals or multifocals) although peripheral vision is distorted; splitting the lights between distance and closer distances (simultaneous vision multifocal contact lenses, intraocular lenses and laser refractive surgery) although contrast is lost and patients often experience glare; or having one eye focused for distance and the other for near (monovision) although depth stereovision is lost and contrast is reduced. Therefore a more natural ‘bionic’ solution is needed.”
“A common cause of sight problems are cataracts, which describe clouding of the lens within the eye which causes vision to be reduced. From early civilisations, the solution commonly used to treat cataracts was simply to push the damaged lens to the side with a needle, restoring light, but leaving the vision very blurry. This was until the introduction of the intraocular lens, by Sir Harold Ridley (1949), who noticed that eyes of World War Two pilots with acrylic fragments from shattered windscreens did not adversely react. He concluded that perspex could be used to construct lens that the eye wouldn’t reject, thus allowing the development of implantable artificial lenses.”
The concluding part of the presentation highlighted potential future intraocular lens designs to restore eye focus mainly based on shape change rather than movement within the eye, fulfilling the bionic lens concept. Professor Wolffsohn also discussed newly developed Aston instrumentation to assess the optical power of the eye during surgery, allowing the intraocular lens to be tuned to give optimum vision. In addition, adaptive optics space age technology will enable advanced optical designs to be evaluated prior to expensive, time-consuming clinical trials.
He concluded; “Whilst the invention of the intraocular lens was a fundamental breakthrough, it doesn’t solve the problem of restoring lost focus from ageing. The muscles in the eye have been shown to continue remain active throughout life. Therefore replacing the rigid intraocular lens with one that moves or changes shape could be used to restore eye focus. Designs that move forward in the eye with attempted eye focus are already on the market, but our research has shown their restoration of eye focus is limited. Furthermore any focusing effect is reduced with time due to the natural lens capsule wrapping itself around the implanted lens mechanics. Second generation implants, which the Aston team are just beginning to implant, consist of two lenses linked by springs, which act as a mini-telescope. Although future advancements such as these could lead to the demise of glasses, probably within a generation, I’d be keen to stress I couldn’t imagine a time when the world would no longer need Optometrists!”
Professor Wolffsohn is part of the Ophthalmic Research Group formed at Aston in 1983 with the objective of advancing the understanding of the development, use, presentation and restoration of ocular function through clinical and applied matters relevant to optometry and ophthalmology.
The standard of optometry courses at Aston is held in very high regard. It has dedicated internationally renowned academics and facilities like the Aston Day Hospital conducting cataract and laser refractive surgery on-site. In the Complete University Guide, Aston is ranked 1st overall in ‘Subjects Allied to Medicine’ which includes Optometry, Audiology and some elements of Biology. This is the third consecutive year that Aston has achieved this ranking.
To find out more about Professor James Wolffsohn and his research activities visit; http://www1.aston.ac.uk/lhs/staff/az-index/wolffjsw/