Astronaut health is a huge concern, as studies have shown muscle and bone mass are at risk on longer missions; that's just what we know about, too. The problem is how to fit out a space station or future moon base with medical equipment compact and safe enough to do the job. Now, thanks to researchers in Canada, there is a compact magnetic resonance imagining (MRI) machine that could one day head to space to help astronauts.
Gordon Sarty, acting chairman of the biomedical engineering division at the University of Saskatchewan in Canada, and his team have developed a compact MRI that could provide detailed images of what's going on inside an astronaut's arms or legs. This mini MRI could weigh less than a ton versus the 11-ton Earth version, would require less power and costs could drop from $2 million to $200,000.
Bringing an MRI to space — even the mini version is not without complications. Though Sarty's version would weigh one twentieth of a conventional version, he still needed to tackle how to revise some of the more dangerous aspects of conventional MRI's for the space environment.
Conventional MRIs work by using radiofrequency coils to send signals to the human body and receive signals in return that help build the picture of the body's insides. Giant superconducting magnets cooled by liquid helium and controlled by gradient coils are also used to control the magnetic fields that produce the exacting slice imagery of the scanned body part.
The magnets are what push up the weight, and the stray magnetic fields could interfere with space station equipment. Then there is the problem of the immense amount of power required to run the gradient coils of conventional machines. They too, could put a strain on space station operations.
Sarty's mini MRI has focused on changing the problematic magnet and coils. As reported in Space.com:
First, it uses a permanent Halbach magnet that is lighter than the superconducting magnet and does not create stray magnetic fields outside the magnet. Second, the compact MRI eliminates the power-hungry gradient coils by using Transmit Array Spatial Encoding (TRASE) that encodes images through the radiofrequency coil alone.
Sarty's team has shown the technology can work. The Halback magnets have proven the can create the required magnetic fields. Experiments with the TRASE coils have shown they can create images inside a conventional MRI without the benefit of the gradient coils.
With the technology proving sound, Sarty's team created a mock up of the mini MRI and presented it at AIAA Space 2012, a conference organized by the American Institute of Aeronautics and Astronautics, last week.
Sarty's goal is to win full funding from the Canadian Space Agency to get the machine to the space station around 2020, to test the concept.
Aside from the data gathering opportunities such a compact MRI would provide when in space, as Sarty told Space.com: "Eventually someone will break a bone in space. We have no idea if that bone will heal."
Many of the space conference attendees reportedly urged Sarty to work on fleshing out the concept on Earth first. There are obvious reasons how a compact MRI would be useful here on Earth — in war zones, medical clinics and smaller hospitals could all benefit from the cheaper, more energy conscious model.
While it's possible now that the technology has been proven someone may run with the concept for the Earth-bound market, Sarty still has his eyes looking towards the stars. He's confident in the potential health benefits such a device could provide for astronauts, but recognizes the goal will only succeed with help from the agencies that run the International Space Station.