Staff Writer

Microwave helmet 'can spot a stroke'

Scientists say they have devised a helmet that can quickly determine whether a patient has had a stroke. It could speed diagnosis and treatment of stroke to boost chances of recovery, the scientists say.

The wearable cap bounces microwaves off the brain to determine whether there has been a bleed or clot deep inside. The Swedish scientists who made the device plan to give it to ambulance crews to test after successful results in early studies with 45 patients.

When a person has a stroke, doctors must work quickly to limit any brain damage. If it takes more than four hours to get to a hospital and start treatment, parts of their brain tissue may already be dying. But to give the best treatment, doctors first need to find out if the stroke is caused by a leaky blood vessel or one blocked by a clot.

A computerized tomography (CT) scan will show this, but it can take some time to organize one for a patient, even if they have been admitted as an emergency to a hospital that has one of these scanners. Any delay in this "golden hour" of treatment opportunity could hamper recovery.

To speed up the process, researchers from Chalmers University of Technology, Sahlgrenska Academy and Sahlgrenska University Hospital (all Göteborg, Sweden), have come up with a mobile device that could be used on the way to hospital.

The helmet uses microwave signals — the same as the ones emitted by microwave ovens and mobile phones but much weaker — to build a picture of what is going on throughout the brain. Tests with an early prototype — a refashioned bicycle helmet — found it could accurately distinguish between bleeds (hemorrhagic stroke) and clots (ischemic stroke), although not 100% of the time.

They have since built and tested a custom-made helmet to better fit skulls of different shapes and sizes, and they have tested it out with the help of nurses and patients at a local hospital ward. Ultimately, they want to fit it into the pillow the patient rests their head on. The researchers say their device needs more testing, but could be a useful aid in the future.

Doctors would probably still need to use other diagnostic methods too, they told Transactions on Biomedical Engineering journal.

Investigator Mikael Persson said, "The possibility to rule out bleeding already in the ambulance is a major achievement that will be of great benefit in acute stroke care."

Shamim Quadir, of the UK's Stroke Association, said, "When a stroke strikes, the brain is starved of oxygen, and brain cells in the affected area die. Diagnosing and treating stroke as quickly as possible is crucial. While this research is at an early stage, it suggests that microwave-based systems may become a portable, affordable, technology that could help rapidly identify the type of stroke a patient has had, and get them treated faster. By diagnosing and treating stroke as early as possible, we can minimise the devastating impact of stroke, secure better outcomes for patients and, ultimately, save lives. Time lost is brain lost."

How a new approach to funding

Alzheimer's research could pay off

More than five million Americans suffer from Alzheimer's disease, the affliction that erodes memory and other mental capacities, but no drugs targeting the disease have been approved by the FDA since 2003. Now a paper by an Massachusetts Institute of Technology (MIT; Cambridge, Massachusetts) professor suggests that a revamped way of financing Alzheimer's research could spur the development of useful new drugs for the illness.

"We are spending tremendous amounts of resources dealing with this disease, but we don't have any effective therapies for it," said Andrew Lo, the Charles E. and Susan T. Harris Professor of Finance and director of the Laboratory for Financial Engineering at the MIT Sloan School of Management. "It really imposes a tremendous burden on society, not just for the afflicted, but also for those who care for them."

Lo and three co-authors have proposed creating a public-private partnership that would fund research for a diverse array of drug-discovery projects simultaneously. Such an approach would increase the chances of a therapeutic breakthrough, they say, and the inclusion of public funding would help mitigate the risks and costs of Alzheimer's research for the private sector.

There would be a long-term public-sector payoff, according to the researchers: Government funding for Alzheimer's research would pale in comparison to the cost of caring for Alzheimer's sufferers in public healthcare programs. The paper's model of the new funding approach called for an outlay of $38.4 billion over 13 years for research; the costs of Medicare and Medicaid support for Alzheimer's patients in 2014 alone is estimated to be $150 billion.

"Having parallel development would obviously decrease the waiting time, but it increases the short-run need for funding," Lo said. "Given how much of an urgent need there is for Alzheimer's therapies, it has to be the case that if you develop a cure, you're going to be able to recoup your costs and then some." In fact, the paper's model estimates a double-digit return on public investment over the long run.

Lo added, "Can we afford it? I think a more pressing question is, 'Can we afford not to do something about this now?'"

The paper, "Parallel Discovery of Alzheimer's Therapeutics," was published in Science Translational Medicine.

Allen Institute examines regions of developing brain

Researchers at the Allen Institute for Brain Science (Seattle) have mapped the development of the mouse brain from the embryo to the adult, creating a preliminary genetic key that allows them to pinpoint the age and location of regions of the developing brain. This work lays the foundation for tracking regions of the mouse brain through development, which could have valuable implications for translational work in human brain developmental disorders. The research, profiling the publicly available Allen Developing Mouse Brain Atlas, is published in the June 19th issue of the journal Neuron.

In order to identify individual brain regions, and their age, researchers frequently turn to using genes that can be found exclusively in that particular region and time point. But truly specific so-called "marker" genes are actually quite rare, said Michael Hawrylycz, investigator at the Allen Institute for Brain Science. "Rather than relying on single genes, we were able to identify combinations of genes and use those combinations to create a unique code that can be used to place regions of the brain in space-time," said Hawrylycz.

The research team also captured evidence of how the brain develops from its earliest form of stacked primordial plates to its adult form with the more familiar geographic regions that begin to correspond to specialized functional divisions of the brain.

"We can now place this important organizational transition from plates to regions within developmental time," said Carol Thompson, lead author and scientific program manager at the Allen Institute for Brain Science. "We already knew this transition took place, but now we understand the mechanics behind it at a much more detailed, molecular level."

The Allen Developing Mouse Brain Atlas serves as an expansion of the original Allen Mouse Brain Atlas and identifies where genes are active in the brain over seven different ages, ranging from prenatal to adult. Rather than profiling every gene in the mouse genome, the researchers selected approximately 2,100 genes with particular importance in development, and used those to identify individual brain regions at different time points.

"The Allen Developing Mouse Brain Atlas works like a Rosetta stone for the developing brain," says Allan Jones, CEO of the Allen Institute for Brain Science. "We can translate how and when genes are expressed into what is happening in the brain developmentally, making this resource a promising tool for better understanding and eventually treating brain developmental disorders and diseases."

PET scans peer into minimally conscious mind

New research by Physics and Astronomy professor Andrea Soddu from the University of Western Ontario (London, Ontario) touts the ability of PET scans to identify patients in a minimally conscious state (MCS) far more accurately than other imaging technologies.

According to his study, PET scans identified 93% of people in a minimally conscious state, and that 74% would recover within the next a year. The functional magnetic resonance imaging (fMRI) identified 45% and 56%, respectively.

Soddu's research, which included colleagues from Belgium and Denmark, was recently published in The Lancet.

"With the PET, if you don't see any metabolic activity in both left and right hemisphere, but just in the cerebellum and brain stem, then you say he or she is in a vegetative state," Soddu said. "If you find some residual metabolic activity in one of the hemispheres, then this is a minimally conscious state patient."

This clinical validation study included patients referred to the University Hospital of Liège, Belgium, between January 2008 and June 2012 who were diagnosed with unresponsive wakefulness syndrome, locked-in syndrome or minimally conscious state with traumatic or non-traumatic causes.

Soddu, whose research focuses on medical physics (neuroscience), said when comparing the resting brain vs. the active brain, the active brain requires more cognitive processes from the patient and, thus, is a key indicator.

"It's only the active paradigm that can tell you if the patient is conscious," he said. "If you find some residual activity in the brain, you cannot conclude this is sufficient for a patient to be conscious. But then, you can compare things with the behavioural evaluation and can say next time we find some residual activity, most probably, the patient is conscious."

Diagnostic assessments are traditionally made using bedside clinical tests — but Soddu said judging the level of awareness in people with severe brain damage can be difficult for many reasons. For instance, subjects may not understand the question, they may complete the task when they're not supposed to or, even, may not want to do the task.

"You should always go for the active paradigm. If you don't find anything, try to see if there is some residual activity," Soddu said. "It's the only way to really be sure if the patient is conscious or not. The moment you don't get any answer, don't stop there. Keep digging."

PET scans also distinguished brain activity in some patients who had been diagnosed as unresponsive by the standard Coma Recovery Scale test.

The bonus of using PET, Soddu said, is when you look at the signal of the PET it's like looking at the stars.

While more accurate, the PET scans are also more invasive and expensive, with not all facilities having access to them, as opposed to fMRI machines. Soddu and colleagues are now working on being able to produce a simulated PET signal using the fMRI machine, thus allowing more access to this diagnostic tool.

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