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age related macular degeneration

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World’s first bionic eye implant has been performed by Manchester surgeons in a patient with dry age-related macular degeneration.

Age-related macular degeneration (AMD) is the most common cause of sight loss in the developed world.

The patient, 80-year-old Ray Flynn, has dry age-related macular degeneration which has led to the total loss of his central vision.

Ray Flynn is using a retinal implant which converts video images from a miniature video camera worn on his glasses.

He can now make out the direction of white lines on a computer screen using the retinal implant.

Ray Flynn said he was “delighted” with the implant and hoped in time it would improve his vision sufficiently to help him with day-to-day tasks like gardening and shopping.

The Argus II implant, manufactured by the US-based company Second Sight, has previously been used to restore some vision to patients who are blind as a result of a rare condition known as retinitis pigmentosa.

Photo PA

Photo PA

The operation, at Manchester Royal Eye Hospital, is the first time it has been implanted in a patient with age-related macular degeneration.

Ray Flynn said he had to sit very close to the TV to see anything.

He had given up going to see Manchester United play football as he cannot make out what is happening.

The operation took four hours and was led by Paulo Stanga, consultant ophthalmologist and vitreo-retinal surgeon at Manchester Royal Eye Hospital and professor of ophthalmology and retinal regeneration at the University of Manchester.

Prof. Paulo Stanga said: “Mr. Flynn’s progress is truly remarkable, he is seeing the outline of people and objects very effectively.

“I think this could be the beginning of a new era for patients with sight loss.”

The bionic eye implant receives its visual information from a miniature camera mounted on glasses worn by the patient.

The images are converted into electrical pulses and transmitted wirelessly to an array of electrodes attached to the retina.

The electrodes stimulate the remaining retina’s remaining cells which send the information to the brain.

In a test, two weeks after surgery, Ray Flynn was able to detect the pattern of horizontal, vertical and diagonal lines on a computer screen using the implant.

Ray Flynn kept his eyes closed during the test so that the medical team could be sure that the visual information was coming via the camera on his glasses and the implant.

He said: “It was wonderful to be able to see the bars on the screen with my eyes closed.”

The implant cannot provide any highly detailed vision – but previous studies have shown it can help patients to detect distinct patterns such as door frames and shapes.

Prof. Paulo Stanga said that in time, Ray Flynn should learn how to interpret the images from the implant more effectively.

Four more patients with dry AMD will receive the implant at Manchester Royal Eye Hospital, as part of a clinical trial.

Prof. Paulo Stanga said: “We hope these patients will develop some central visual function which they can work in alongside and complement their peripheral vision.

“We are very excited by this trial and hope that this technology might help people, including children with other forms of sight loss.”

The Argus II costs about $240,000, including treatment costs, although all the patients on the trial will be treated free of charge.

Gregoire Cosendai of Second Sight Medical Products, described the AMD study as “totally groundbreaking research”.

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According to British scientists, the prospect of reversing blindness has made a significant leap.

An animal study in the journal Nature Biotechnology showed the part of the eye which actually detects light can be repaired using stem cells.

The team at Moorfields Eye Hospital and University College London say human trials are now, for the first time, a realistic prospect.

Experts described it as a “significant breakthrough” and “huge leap” forward.

Photoreceptors are the cells in the retina which react to light and convert it into an electrical signal which can be sent to the brain.

However, these cells can die off in some causes of blindness such as Stargardt’s disease and age-related macular degeneration.

There are already trials in people to use stem cells to replace the “support” cells in the eye which keep the photoreceptors alive.

Now the London-based team has shown it is possible to replace the light-sensing cells themselves, raising the prospect of reversing blindness.

An animal study in the journal Nature Biotechnology showed the part of the eye which actually detects light can be repaired using stem cells

An animal study in the journal Nature Biotechnology showed the part of the eye which actually detects light can be repaired using stem cells

They have used a new technique for building retinas in the laboratory. It was used to collect thousands of stem cells, which were primed to transform into photoreceptors, and injected them into the eyes of blind mice.

The study showed that these cells could hook up with the existing architecture of the eye and begin to function.

However, the effectiveness is still low. Only about 1,000 cells out of a transplant of 200,000 actually hooked up with the rest of the eye.

Lead researcher Prof. Robin Ali said: “This is a real proof of concept that photoreceptors can be transplanted from an embryonic stem cells source and it give us a route map to now do this in humans.

“That’s why we’re so excited, five years is a now a realistic aim for starting a clinical trial.”

The eye is one of the most advanced fields for stem cell research.

It is relatively simple as the light sensing cells only have to pass their electrical message on to one more cell in order to get their message to the brain, unlike an attempt to reverse dementia which would require cells to hook up with far more cells all across the brain.

The immune system is also very weak in the eye so there is a low chance of the transplant being rejected. A few cells can also make a big difference in the eye. Tens of thousands of stem cells in the eye could improve vision, but that number of stem cells would not regenerate a much larger organ such as a failing liver.

Researchers say that early results from the world’s first human trial using embryonic stem cells to treat diseases of the eye suggest the method is safe.

US firm Advanced Cell Technology told The Lancet how two patients who had received the retinal implants were doing well, four months on.

Trials of the same technique have also started at London’s Moorfields Eye Hospital.

But experts say it will be years before these treatments are proven.

The aim of these first human studies is to establish that the treatment is safe to use.

The treatment takes healthy immature cells from a human embryo, which are then manipulated to grow into the cells that line the back of the eye – the retina.

Experts hope that by injecting these cells into a diseased eye, they will be able to restore vision for people with currently incurable conditions such as Stargardt’s disease – one of the main causes of blindness in young people.

Advanced Cell Technology, along with the Jules Stein Eye Institute at the University of California, Los Angeles, are reporting their first experiences with this treatment in human trials.

The study involved one elderly patient in her 70’s with dry age-related macular degeneration – the leading cause of blindness in the developed world – and another female patient in her 50’s with Stargardt’s disease.

Both had very poor vision and were registered blind.

Each patient was given an injection containing 50,000 of the retinal pigment epithelium cells into one of their diseased eyes.

After surgery, structural evidence confirmed the cells had attached to the eye’s membrane as hoped, and continued to survive throughout the next 16 weeks of the study.

Furthermore, the procedure appeared to be safe, causing no signs of rejection or abnormal cell growth.

Although this study is not designed to see if the procedure actually works, the researchers say their results do suggest that their patients’ vision has improved slightly.

But they say it is still too soon to make any firm conclusions and that many more years of investigation will be needed to confirm that the treatment is both safe and effective.

The researchers told The Lancet: “The ultimate therapeutic goal will be to treat patients earlier in the disease processes, potentially increasing the likelihood of photoreceptor and central visual rescue.”

But even if this does become possible, such treatments would face stiff opposition by critics who say it is ethically wrong to use human embryonic tissue.

Dr. Dusko Ilic, Senior Lecturer in Stem Cell Science at Kings College London, said that these early findings did not necessarily hint towards a viable treatment.

“We should keep in mind that people are not rats.

“The number one priority of initial clinical trial is always patient safety. If everyone expects that the blind patients will see after being treated with human embryonic stem cell-derived retinal pigment epithelium, even if the treatment ends up being safe (which is what Advanced Cell Technology are trying to determine in this trial), they risk being unnecessarily disappointed.”