Bionic implants: 'We have the technology'
As scientists restore sight to a blind man, Richard Gray explains how human beings can now be rebuilt from top to toe with artificial parts .
Claudia Mitchell demonstrates the functionality of her "bionic arm"
1 Comment
For the first time in more than a decade, Miikka Terho was able to glance at a clock and read the time. It was a simple task, but one he had been unable to do since he was robbed of his sight by disease. Mr Terho, 46, a financial consultant from Finland, was one of three patients who had their sight temporarily restored using artificial light sensors and microchips placed on the retina at the back of their eyes by doctors in Germany.
This extraordinary melding of man and machine proves that we finally have the technology to create real-life bionic humans. In the 1970s TV series, The Six Million Dollar Man, Lee Major’s character had his body rebuilt using bionic technology, leaving him “better, stronger, faster”. Now, cutting-edge research is producing synthetic body parts to replace damaged tissues, limbs, organs and senses. In most cases it is used to improve a patient’s quality of life, but in others it is saving lives.
Here we examine how science can potentially kit out a human being from head to toe to create a real bionic man.
Brain
By far the most important, and also the most complex, organ in the body is the brain. It controls our movements and our breathing, makes sense of the world and stores the memories that help form our personalities. Damage to the brain from accidents or illnesses such as strokes can be catastrophic, ranging from paralysis to memory loss. But some scientists believe they may have found a way to repair this damage – a prosthetic brain.
Dr Theodore Berger, from the University of Southern California, has been developing a device that can be implanted into the brain to restore memory functions, modelling the complex neural activity that takes place in the hippocampus, which is responsible for forming new memories.
The device – a microchip that encodes memories for storing elsewhere in the brain – has been tested using tissue from rats’ brains, and researchers are planning trials on live animals. They hope it will provide a way of restoring memory function in patients who have suffered damage to their hippocampus from a stroke, an accident or from Alzheimer’s disease.
Eyes
Around one million people in Britain suffer from two of the most common forms of blindness: macular degeneration and retinitis pigmentosa. But doctors in Germany last week restored sight to three blind patients by implanting chips lined with electronic sensors – similar to those found in digital cameras – into the back of their eyes. When light hits these sensors, they produce electrical impulses that pass into the optical nerve behind the eye and into the brain. The patients reported being able to distinguish objects such as fruit and cutlery, and even read their own name.
Miikka Terho was one of the first to have the implant and saw his life transformed over the three-month trial, before the implant was removed. He went from being completely blind to being able to make out fuzzy black-and-white shapes that allowed him to read the time.
“When I first got the implant I could tell I was seeing something, but I couldn’t really make out what it was – it was like my sight was a muscle that I hadn’t used in a long time and it needed training to get used to recognising things again,” he says.
“Later I was able to see people and tell if someone lifted their arm or if someone was taller than someone else. They were too fuzzy to distinguish faces, but being able to see like that would help me to be more independent and walk in unfamiliar surroundings – to live a more normal life.”
Professor Eberhart Zrenner, who led the research at the University of Tuebingen, has already begun work on improving the detail that the patients can see by changing the power supply – currently the chip has an external supply that must be transmitted through the skin via a magnetic link.
“We also want to have the implant do some intelligent processing that can help to enhance the contrast and the graininess of the image,” he says.
A larger trial of the device is now being planned and will include patients from
the UK – but it is by no means the only approach being taken. While most research is aimed at helping patients who have lost their sight, some scientists hope they may be able to enhance the vision of healthy people, too. Artificial lenses that have microscopic circuits fixed to them could be used to produce wearable displays that beam maps, computer displays and even zoom functions to the wearer.
Ears
The bionic ear has been around for more than 40 years, and many thousands of patients are already wearing them. Cochlear implants turn sound into electronic pulses that are transmitted to the brain, allowing the wearer to “hear”. Unfortunately, the devices are unable to tune in to specific sounds, so in noisy environments patients can struggle to hear speech and find music hard to enjoy.
However, scientists at La Trobe University, Australia, have, by studying the way in which the ear transmits information to the brain, produced a device that behaves far more like a human ear.
Heart
Artificial hearts, essentially miniaturised pumps, are often implanted into patients to help their damaged organs pump blood around their bodies while they are waiting for transplants. And last month doctors in Italy gave a 15-year-old boy the first permanent artificial heart implant. One company in France, Carmat, has developed a prototype for a fully artificial heart that would replace the organ altogether. Heart specialist Alain Carpenteir, the doctor behind the device, uses hydraulic pumps to push blood around the body. It works like a natural heart, where blood is drawn into cavities inside the organ before being pushed out to the arteries. Surgeons plan to perform the first implant in humans in late 2011.
Arm
In July, Patrick Kane, a 13-year-old schoolboy from London, was transformed into a bionic boy when he was fitted with a prosthetic arm by the Livingston-based firm Touch Bionics. Their revolutionary iLimb Pulse hand means Patrick, who lost his left hand after falling victim to meningitis when he was nine months old,
can even squash grapes between his fingers. “It’s the little things that the hand allows me to do that have really made the difference,” says Patrick. “I can open bottles with both hands now, hold my fork and tie my shoelaces. ”
His prosthesis works by using two electrodes that make contact with the skin on his upper arm. When he tenses a muscle, tiny pulses of electricity from the nerves beneath the electrodes cause the hand to close; when he tenses another, the hand opens.
Researchers are working on prosthetic limbs that will allow wearers even more control. By mapping how the neural networks are used to control limb movements, they can learn how robotic arms can be controlled in the same way as a real, natural arm. Some approaches use electrodes implanted beneath the skin; others use ones on top of the skin. By picking up tiny signals from the brain when someone thinks about moving their arm, the robotic prosthesis can be made to replicate the movement.
Hugh Gill, chief technical officer at Touch Bionics, says: “What we’re looking at is how you can map the signals from the brain so that you can have discrete control of individual digits on a prosthetic hand and rotate the wrist. The ideal situation is that when you go to reach for an object, the hand responds in the way you would expect a real hand to.
“One of the other things a number of people are looking at, and again we are interested in, is adaptive devices that fit around existing limbs like an arm or a leg and provide additional power.”
Muscles
Some researchers are attempting to find ways of replacing individual muscles rather than whole limbs to provide bionic treatments for people who have suffered serious sporting injuries or lost muscles in accidents. They are using synthetic polymer gels that expand and contract in response to small electrical currents to create synthetic muscles for replacing heart valves, sphincter muscles and, eventually, larger muscles.
Scientists at Nasa’s Jet Propulsion Laboratory in Pasadena are aiming to develop an arm powered by bionic muscles made from these “electroactive polymers” that would be capable of winning an arm-wrestling contest. Dr Richard Baker, from the University of St Andrews, is also working with polymer gels, but hopes to produce material that will contract and expand in response to the kind of chemical signals that are found in the body.
Scientists at the University of Texas have produced artificial muscles that are more than 100 times more powerful than natural muscle, using an elastic metal wire that bends when it is heated and returns to normal when cooled down.
Tendons
Researchers at Manchester University are developing artificial tendons to help patients who have severed or injured their own. Using finely spun fibres of plastic material, the synthetic tendons behave just like the natural tissue and can be implanted into a patient to restore movement.
Professor Sandra Downes, from the school of materials at Manchester University, says the implants would encourage the body to heal itself and would gradually break down.
The team is about to start pre-clinical trials and hopes to have bionic tendons on the market within five years.
Touch
Even with the most advanced prosthetics available, patients with robotic arms still suffer from being unable to feel what they are touching. This important sense allows us to enjoy sensuality, control how hard we grip objects and even helps us form opinions about people we meet, for instance from their handshake.
Scientists in Italy have been working on a synthetic skin that gives robots a sense of touch. Although this was initially developed for robots, some researchers at the Italian Institute of Technology are developing ways of feeding information back from the synthetic skin to patients’ nerve cells.
The device – a microchip that encodes memories for storing elsewhere in the brain – has been tested using tissue from rats’ brains, and researchers are planning trials on live animals. They hope it will provide a way of restoring memory function in patients who have suffered damage to their hippocampus from a stroke, an accident or from Alzheimer’s disease.
Eyes
Around one million people in Britain suffer from two of the most common forms of blindness: macular degeneration and retinitis pigmentosa. But doctors in Germany last week restored sight to three blind patients by implanting chips lined with electronic sensors – similar to those found in digital cameras – into the back of their eyes. When light hits these sensors, they produce electrical impulses that pass into the optical nerve behind the eye and into the brain. The patients reported being able to distinguish objects such as fruit and cutlery, and even read their own name.
Miikka Terho was one of the first to have the implant and saw his life transformed over the three-month trial, before the implant was removed. He went from being completely blind to being able to make out fuzzy black-and-white shapes that allowed him to read the time.
“When I first got the implant I could tell I was seeing something, but I couldn’t really make out what it was – it was like my sight was a muscle that I hadn’t used in a long time and it needed training to get used to recognising things again,” he says.
“Later I was able to see people and tell if someone lifted their arm or if someone was taller than someone else. They were too fuzzy to distinguish faces, but being able to see like that would help me to be more independent and walk in unfamiliar surroundings – to live a more normal life.”
Professor Eberhart Zrenner, who led the research at the University of Tuebingen, has already begun work on improving the detail that the patients can see by changing the power supply – currently the chip has an external supply that must be transmitted through the skin via a magnetic link.
“We also want to have the implant do some intelligent processing that can help to enhance the contrast and the graininess of the image,” he says.
A larger trial of the device is now being planned and will include patients from
the UK – but it is by no means the only approach being taken. While most research is aimed at helping patients who have lost their sight, some scientists hope they may be able to enhance the vision of healthy people, too. Artificial lenses that have microscopic circuits fixed to them could be used to produce wearable displays that beam maps, computer displays and even zoom functions to the wearer.
Ears
The bionic ear has been around for more than 40 years, and many thousands of patients are already wearing them. Cochlear implants turn sound into electronic pulses that are transmitted to the brain, allowing the wearer to “hear”. Unfortunately, the devices are unable to tune in to specific sounds, so in noisy environments patients can struggle to hear speech and find music hard to enjoy.
However, scientists at La Trobe University, Australia, have, by studying the way in which the ear transmits information to the brain, produced a device that behaves far more like a human ear.
Heart
Artificial hearts, essentially miniaturised pumps, are often implanted into patients to help their damaged organs pump blood around their bodies while they are waiting for transplants. And last month doctors in Italy gave a 15-year-old boy the first permanent artificial heart implant. One company in France, Carmat, has developed a prototype for a fully artificial heart that would replace the organ altogether. Heart specialist Alain Carpenteir, the doctor behind the device, uses hydraulic pumps to push blood around the body. It works like a natural heart, where blood is drawn into cavities inside the organ before being pushed out to the arteries. Surgeons plan to perform the first implant in humans in late 2011.
Arm
In July, Patrick Kane, a 13-year-old schoolboy from London, was transformed into a bionic boy when he was fitted with a prosthetic arm by the Livingston-based firm Touch Bionics. Their revolutionary iLimb Pulse hand means Patrick, who lost his left hand after falling victim to meningitis when he was nine months old,
can even squash grapes between his fingers. “It’s the little things that the hand allows me to do that have really made the difference,” says Patrick. “I can open bottles with both hands now, hold my fork and tie my shoelaces. ”
His prosthesis works by using two electrodes that make contact with the skin on his upper arm. When he tenses a muscle, tiny pulses of electricity from the nerves beneath the electrodes cause the hand to close; when he tenses another, the hand opens.
Researchers are working on prosthetic limbs that will allow wearers even more control. By mapping how the neural networks are used to control limb movements, they can learn how robotic arms can be controlled in the same way as a real, natural arm. Some approaches use electrodes implanted beneath the skin; others use ones on top of the skin. By picking up tiny signals from the brain when someone thinks about moving their arm, the robotic prosthesis can be made to replicate the movement.
Hugh Gill, chief technical officer at Touch Bionics, says: “What we’re looking at is how you can map the signals from the brain so that you can have discrete control of individual digits on a prosthetic hand and rotate the wrist. The ideal situation is that when you go to reach for an object, the hand responds in the way you would expect a real hand to.
“One of the other things a number of people are looking at, and again we are interested in, is adaptive devices that fit around existing limbs like an arm or a leg and provide additional power.”
Muscles
Some researchers are attempting to find ways of replacing individual muscles rather than whole limbs to provide bionic treatments for people who have suffered serious sporting injuries or lost muscles in accidents. They are using synthetic polymer gels that expand and contract in response to small electrical currents to create synthetic muscles for replacing heart valves, sphincter muscles and, eventually, larger muscles.
Scientists at Nasa’s Jet Propulsion Laboratory in Pasadena are aiming to develop an arm powered by bionic muscles made from these “electroactive polymers” that would be capable of winning an arm-wrestling contest. Dr Richard Baker, from the University of St Andrews, is also working with polymer gels, but hopes to produce material that will contract and expand in response to the kind of chemical signals that are found in the body.
Scientists at the University of Texas have produced artificial muscles that are more than 100 times more powerful than natural muscle, using an elastic metal wire that bends when it is heated and returns to normal when cooled down.
Tendons
Researchers at Manchester University are developing artificial tendons to help patients who have severed or injured their own. Using finely spun fibres of plastic material, the synthetic tendons behave just like the natural tissue and can be implanted into a patient to restore movement.
Professor Sandra Downes, from the school of materials at Manchester University, says the implants would encourage the body to heal itself and would gradually break down.
The team is about to start pre-clinical trials and hopes to have bionic tendons on the market within five years.
Touch
Even with the most advanced prosthetics available, patients with robotic arms still suffer from being unable to feel what they are touching. This important sense allows us to enjoy sensuality, control how hard we grip objects and even helps us form opinions about people we meet, for instance from their handshake.
Scientists in Italy have been working on a synthetic skin that gives robots a sense of touch. Although this was initially developed for robots, some researchers at the Italian Institute of Technology are developing ways of feeding information back from the synthetic skin to patients’ nerve cells.
http://www.telegraph.co.uk/science/8114920/Bionic-implants-We-have-the-technology.html
