Lasers have revolutionised sight correction procedures and now new techniques and products are about to advance the eye-care revolution, as Josh Sims discovers
Anyone of a certain age who finds themselves donning bi-focals, or having to swap between glasses for mid-to-longer range vision and another pair for reading, may be able to ditch them over the next few years.
PixelOptics digital eyewear may well replace traditional progressive lenses. Containing a layer of transparent liquid crystal, these new lenses electronically alter how the lenses refract light, meaning they will adapt from reading the paper to driving in 0.025 seconds. Indeed, the first generation of the lenses hit the market last year.
That may give a lifestyle lift for those who either don’t like the idea of surgical correction of diminishing eyesight or are not suitable candidates for the procedure. But for those not averse to going under the laser, advances are being made in that arena too. Replacement of the fundamental technology may not be imminent but, according to Steve Schallhorn, global medical director of Optical Express, the world’s biggest provider of laser eye surgery, the next decade will see great improvement in the systems that underpin it.
Laser sight correction surgery is one of the fastest improving fields in medicine
“Like electronics or automobile technology, it only goes in one direction – better,” he says. “In fact, laser sight correction surgery is one of the fastest improving fields in medicine. Instead of four airbags in a car, we’ll have eight or twelve, and the same advance will happen in surgery.”
He specifically cites improvements in diagnostics to work out who is and isn’t suitable for surgery and to minimise potential complications. Right now, the standard Excimer laser technology – “which can etch your name on a red blood cell,” he says – is already ahead of the variability in human healing. How to modulate that response may prove of greater significance than improvements to the hardware itself.
But some new machinery is coming to the fore. Karen Sparrow, education adviser for the Association of Optometrists, singles out wave front technology. This gives measurement of the variable curvature of the cornea across its surface, to allow for both better contact lenses and more accurate laser surgery, as many possible aberrations particular to each individual eye can be corrected.
“While laser surgery is irreversible and has its pros and cons, the laser remains the best cutting tool we have - it’s less about changing the system itself, as the computing power driving it,” she says. “The idea that we might just get a new cornea put in seems remote, even if stem cell research allows us to grow them. That still leaves the question of how best to put them in.”
So might artificial eyes remain the stuff of science fiction for some time to come? Mr Schallhorn says it is more likely that one of the most common problems – the lens losing its plasticity in people after middle-age and so its ability to focus – may be treated by new medicines, cutting out the need for surgery altogether.
But Ms Sparrow notes that progress in materials sciences may one day provide a more futuristic solution, after all, we have long known that the eye tolerates Perspex as a result of Second World War pilots having shards embedded in their eyeballs when their canopies were shattered.
Sundeep Kheterpal, a consultant ophthalmic surgeon for Optegra Surrey Eye Hospital, hopes to see new medical technology tackle what he calls the Holy Grail of his field. This is not the specific cornea problems that can affect the young, or the lens problems that blight the older population, but the narrowing range of focus that can affect the much bigger age group in between. He suggests we may see the replacement of lenses with a material that could then be set by an external light or thermal source to the right prescription. The technology already exists, but finessing it may take another 20 years.
“We’re at a very exciting stage for eye surgery. Laser treatment has become the baseline standard after being considered very avant garde just 15 years ago,” he says. “We can expect to see not only an extension of the limits to include those people who currently can’t be treated, but a much more personalised treatment more closely aligned with the different things that different people want to achieve from surgery too. We’re now ready to move to the next level.”
Advice from the Royal College of Ophthalmologists
Complications occur in less than 5 per cent of cases, but make sure your consultant outlines all the risks. Flap complications arise in 0 to 4 per cent of cases, but can usually be corrected with little or no loss of vision. Some people have a problem with dry eyes in the months after surgery and artificial tear supplements might be needed in the long term. Many patients have experienced glare or halo effects when driving at night, particularly just after treatment. This is more likely the higher the correction that has been made, but is rarely severe. In rare cases, excessive thinning of the eye wall can cause the shape of the eye to be unstable after treatment. Severe loss of vision is very unusual, but some patients could require corneal surgery or hard contact lenses to restore vision. You should find out exactly how frequently your surgeon has experienced complications and why.