New ways to detect brain activity | Science| In-depth reporting on science and technology | DW | 16.06.2014
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New ways to detect brain activity

Formula One star Michael Schumacher is awake again after almost six months in a coma. Belgium researchers have found new ways of detecting brain activity in patients who won't wake up.

Michael Schumacher is now conscious and responds to simple instructions, his manager reported on Monday (16.06.2014). The 45-year-old was awakened from an artificial coma by his doctors. But what about patients who can't be brought back to consciousness? A new technique that could give hope to families of patients in a persistent vegetative state has been developed in Belgium.

Scientists claim that their new scanning method can pick up radiation from active molecules injected into the blood to assess the level of glucose metabolism in different parts of the brain – as these simply "light up" on the scan and may mean that a patient could come out of the comatose state.

Michael Schumacher Portrait. (Photo: Marcus Brandt/dpa)

Schumacher is awake after six months in a coma, but it's not clear what condition he's in

Hidden signs of consciousness

Experts say that up to 40 percent of patients are misdiagnosed by current bedside tests for signs of life when they're in a persistent vegetative state. Medical professionals and families who've gone through the anguish of having to decide about whether to turn off a life support machine have been calling for help to allow them to make an educated decision. Research by scientists in Belgium may be the help they need.

"We are interested in the functioning of the brain in patients who are comatose and who can develop chronic disorders of consciousness such as the vegetative state," Steven Laureys, director of the Coma Science Group at University Hospital in Liege, told DW. "Is there any form of consciousness and if not can we predict the chances of recovery? We try to use these new technologies, brain scans, to directly measure what's happening in their brain."

Laureys says that roughly one third of the cases sent to his center come in with a wrong diagnosis. That's why it's so important that doctors use standardized tools, explains Laureys - to not miss signs of consciousness.

Detecting brain activity

Research at the Belgian hospital focuses on two different techniques. The first one is functional MRI testing. Doctors ask a patient to lift their hand. If he isn't responsive, that doesn't necessarily mean that he's fully unconscious - he could be paralyzed as well.

That's why the doctors also look at the patient's brain activity. Sometimes they can see on the MRI that the motor-cortex in the patient's brain is activated when he's asked to move his hand. That means he can process the question, he just can't move.

The other test is the PET scan, where a marker fluid is injected into the patient's brain. "Injecting radioactively labeled glucose into the brain is using a lot of energy, so we can visualize the glucose uptake in the brain," Laureys explained. "If you're comatose or unresponsive, the brain shows a very low activity in the so-called consciousness network. But as soon as there are minimal signs of consciousness, there start to be highlights in the brain that have near normal activity."

Patients with these signs of consciousness also show better signs of recovery at the one-year follow-up exams.

Steven Laureys portrait. (Photo: ULg Houet)

Laureys: doctors need to make sure not to miss signs of consciousness

Helping families in times of need

Better prognostic information would also help patients and their families make better decisions about the care they need. Judy Taylor runs the charity "Brain Injury Is Big" in the UK, which she set-up with four other women whom she met in a neuro-disability ward in London. It was after Judy's husband Simon had been seriously hurt in an accident.

"After about 10 months it was confirmed that he was in a persistent vegetative state, but over the next year and a half he did actually begin to show signs of emerging from a vegetative state to a minimally conscious one," Taylor told DW. "He would smile intermittently if he heard a friendly voice, or he would lift up his thumbs or his hands if you asked him to. It was enough to know that he was making some improvement, even if it was only very little."

Simon died when he couldn't fight off a bout of pneumonia in April 2012. Such a natural death is hard enough for surviving family and friends. But what happens when the body of a patient degrades to the point at which there is almost nothing left and their family is faced with the question of whether or not to switch-off life support?

That's what happened to Christopher Watson. After two and a half years on life support, his family decided the quality of his life had deteriorated so much that his suffering had to end. But it took two years in the UK courts for them to get approval.

"The legal battle that we faced was something that I would not wish upon anybody," Christopher's brother Andrew Watson said.

Expanding the research

The impact of the research done by Laureys and his team in Belgium could be huge - offering a clear indication, for the first time, of which patients may stand a chance of recovery and for whom there is little chance of regaining any meaningful quality of life. That could help avoid lawsuits like the one the Watson family had to go through.

Laureys ran his trial on just over a hundred people and he hopes to repeat it on a much larger scale. Although the technology is expensive, neuroscientists believe it will become cheaper and more common in hospitals in the future and provide a real breakthrough for the diagnosis and prognosis of patients with severe brain injury.

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