Friday, 30 December 2011
HEALTH: VISION FOR THE FUTURE
TO some, it probably sounds like something from science fiction. To others, the notion that one day soon medics will be able to give the blind back their sight is just wishful thinking.
Certainly to the group of specialist medics who gathered at a meeting room at Edinburgh's Royal Infirmary 100 years ago to launch an organisation aimed at harnessing expertise on eye disorders and treatments, the idea of growing replacement body cells from dead donors to repair damaged eyes could only be straight from the pages of an HG Wells novel or, indeed, Mary Shelley's Frankenstein.
Rather than dabble with such fantasy, the new members of the fledgling Scottish Opthalmological Club were far more concerned with new instruments that might enable them to look deep within the eye, and how to tackle infections caused by the scourge of TB and syphilis.
Now, however, a century since the exclusive club held its inaugural meeting in the Capital, modern medical science in Edinburgh is on the verge of a major breakthrough, one that could offer hope to millions.
Soon the first patient in a revolutionary clinical trial aimed at reversing corneal blindness will undergo treatment using material from adult donor stem cells that have been harvested after death and grown in Scottish National Blood Transfusion laboratories.
If the trial is successful, stem cell treatment could bring sight to millions around the world whose lives have been plunged into darkness.
Treatment on such an enormous scale is certainly a far cry from what was on offer at the start of the 20th century when a handful of ophthalmologists from around the country met to share their revolutionary findings in the hope of improving the quality of care for their patients.
Their work is now being marked in a new exhibition in Surgeons' Hall Museum in Nicolson Street - a timely reflection on how their generation helped pave the way towards a modern era that could well lead to the blind being given the chance to see again. Yet, as Professor Bal Dhillon of the Princess Alexandra Eye Pavilion admits, anyone even suggesting the use of cells from dead donors, grown in a lab then transplanted into patients' unseeing eyes back in 1911 may well have found themselves introduced to another area of medical care - the asylum.
"There is work going on now which back then would have been seen as science fiction," agrees Professor Dhillon, whose team hope to carry out the first corneal stem cell surgery on a trial patient within months. "We have a number of stem cell programmes and genetic research going on now which in 1911 would certainly never have been dreamed of."
At the forefront of his work is the astonishing technical advance that means limbal cells can be harvested - with consent from deceased adult donors - a process far less controversial than stem cells removed from embryos. The cells are then grown in the lab and later injected into patients' eyes to replace diseased corneal cells and to restore sight.
The trials were first suggested two years ago, but have been delayed while the Scottish Blood Transfusion Service laboratory waited for approval from the Medicines and Healthcare products Regulatory Agency (MHRA) to carry out the work. The lab is understood to be one of the first to hold such a licence.
"The lab side of things has just come to fruition and we are hoping to start first patient treatments later this year," confirms Professor Dhillon. "Getting to this stage has been a major challenge."
The go-ahead could have global ramifications. Corneal diseases are second only to cataracts as the major cause of blindness and around 20 million people are thought to be affected. And while corneal blindness can be treated using transplants or tissue grafts, both carry a high risk of infection. On top of that a shortage of human corneal donors means only a small number can ever hope for treatment.
But while Professor Dhillon and his Chalmers Street-based team prepare for their ground-breaking trial, the medics who gathered in 1911 had equally dramatic advances to debate.
Their profession was at a unique point in its history. Indeed it was a year that would become a turning point in eye treatment.
"It was the year an ophthalmologist won the Nobel Prize, Allvar Gullstrand was the only one to do so," recalls Professor Dhillon. "He won it for developing an understanding of the physics of how the eye works.
"But it was also the year that the slip lamp microscope was introduced which allowed very good detailed description of what goes on in the eye. Until then, we didn't really understand why certain diseases produced certain problems."
It was against that rapidly evolving background that a group of Edinburgh-based opthalmologists formed the Scottish Opthalmologists Club (SOC). Among them was world renowned expert Harry Traquair, whose work on visual field testing - which determines the extent of a patient's side vision - formed the basis of eye tests to establish glaucoma. Back then they also faced problems which, thanks to antibiotics and modern medicines, are now relatively rare.
"In 1911, infections were a big problem. TB and syphilis were common and can cause eye infections," explains Professor Dhillon, who is a member of the SOC. "There were a lot of infections that carried people off at an early age which we now have treatment for.
"On the other hand, HIV wasn't around then. It affects the immune system and so leaves the patients susceptible to eye infections."
A key area of modern research at the Eye Pavilion looks into macular degeneration - a condition that in 1911 was put down to old age. "Macular degeneration is often under-diagnosed and is a major cause of older people becoming registered blind," says Professor Dhillon. "What is concerning now though is that we are seeing people in their early 50s with it, so we want to find out what is causing that."
Research has found some people have a genetic disposition to it while others have a natural protection against the condition.
"There are two types of macular degeneration, wet and dry. Wet is rapid and takes away vision fairly quickly unless picked up. Macular degeneration produces leaky blood vessels, but it can be treated with injections into the eye to reduce the condition's progress.
"If you can understand why it happens and where genes have susceptibility, you can tailor treatments to target those problems. In 1911 that would be like science fiction."
As would treatments and monitoring programmes that help identify patients at risk from diabetic retinopathy, known in 1911 but which had no effective treatment.
But Prof Dhillon warns the rapid advances of the past century might not be matched in the next unless vital funding for research is found. "Funding is becoming increasingly difficult to come by. Cancer and heart disease are major priorities of course, but good quality of life is important too. How would we manage if we couldn't see? The answer is that we couldn't or life would be such a struggle, and there'd be extra costs looking after people, a loss of independence and a loss of the joy of living.
"There is a need to carry forward the work of the past century into the next 100 years."
Looking back
Some surgeons took special interest in eye conditions in the late 1700s as soldiers and sailors returning home from the wars against France were suffering infections that led to loss of vision.
Some surgeons took special interest in eye conditions in the late 1700s as soldiers and sailors returning home from the wars against France were suffering infections that led to loss of vision.
Early treatment was harsh. Blood-letting, which involved scarring of the eyelids, was believed to help improve circulation but often simply led to death.
One surgeon, John Taylor, became known as a coucher or cataract surgeon, but his dubious method of breaking up cataracts in the eye often caused more harm than good. He later confessed to blinding hundreds of patients and was accused of accelerating blindness in composers George Bach and Johan Sebastian Bach.
By 1822 the Capital had its own Edinburgh Eye Dispensary followed by an Eye Infirmary (there was another in Dalkeith) to cater for miners.
The city's first ophthalmic surgeon was appointed in 1855. William Walker became oculist to Queen Victoria.
Photography and retinal cameras help transform eye treatment by enabling specialists to see inside the eye.
n Sight for Scotland: 100 years of ophthalmology, is at Surgeons' Hall Museum, Nicolson Street.
Edinburgh Evening News September 14,2011
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