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Researchers hope to deploy the device to the International Space Station to study the effects of space travel on humans

While mankind has been sending men and women into space for the past five decades, the effects of spaceflight on the human body are still only partially understood.  One key obstacle is that many forms of high-resolution medical scanning equipment is too bulky and heavy to transport into space for use in orbiting space stations.

I. Bringing an MRI up to the ISS?

A key example is the magnetic resonance imaging (MRI) machines.  On Earth they provide the capability to image tissues at a fidelity not possible with other types of scans.  A typical MRI machine costs around $1M USD and weighs about 11 tons due to its bulky liquid-helium cooled superconducting magnets.  Also a traditional MRI could endanger space state residents -- its gradient coils consume massive amounts of power in short bursts and the magnets can create stray magnetic fields that could disrupt life support and other mission-critical systems.

The chairman of the Canadian University of Saskatchewan's Biomedical engineering department hopes to change that, though.  Chairman Gordon Sarty heads a team that has developed a miniature version of the scanner that weighs less than a ton and costs as little as $200,000.

Micro MRI
A full-size mockup of Professor Sarty's reimagined MRI
[Image Source: Gordon Sarty / University of Saskatchewan]

An initial deployment to the International Space Station (ISS) may involve a 1/20th of a ton device, only capable of scanning limbs, to study bone mass and vasculature.  However, Professor Sarty would like to build a full size scanner for the station eventually.  He comments in an NBC News interview, "I would like to build a facility-class, whole-body-sized MRI.  Such a project would require an agreement between the ISS space agencies."

II. Initial Findings Look Promising

At the American Institute of Aeronautics and Astronautics' Sept. 13 AIAA Space 2012 conference Professor Sarty and his team presented their findings.

Their instrument employs a couple of key advances.  First, it utilizes a permanent Halbach magnet -- the primary source of the large weight reduction.  Halbach magnets are a construct of permanent magnets arranged in an array such that they increase each other’s magnet fields within one region and nullify it within another.  In a cylindrical configuration -- a configuration being explored for both motor applications and imaging equipment like Professor Sarty's micro-MRI -- in the ideal case there is an intense field within the cylinder and virtually no field outside of it.

Halbach magnet
A Halbach magnet [Image Source: PERDaix]

Thus the Halbach magnet cylinder also solves a couple of the other issues as it draws no power and produces minimal magnetization outside the cylinder.  To further reduce power, the coil system is modified to only need the radiofrequency coil -- a design called the Transmit Array Spatial Encoding (TRASE).

While the result may be tailor-fit for space applications, Professor Sarty says its qualities like reduced weight and low power consumption could make it well suited for terrestrial applications, as well, such as battlefield deployments (the device could be loaded aboard a truck and run off of batteries).

ISS wide
The final target deployment is the ISS. [Image Source: NASA]

While conference attendees reportedly urged Professor Sarty to set his eyes on these earthbound applications first, he has his sights firmly set on space and is lobbying the Canadian Space Agency to deploy a prototype to the ISS.  He comments, "Eventually someone will break a bone in space.  We have no idea if that bone will heal."

Source: NBC News



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It's cheaper but is it as good?
By havoti97 on 9/23/2012 5:07:50 PM , Rating: 3
The superconducting magnets in traditional MRI machines produce very, very strong magnetic fields. 1.5T is typical but 3T is beginning to show up in the market. Image quality is directly correlated with the magnetic field. There are already machines that use permanent magnets, but they produce fields an order of magnitude lower, like 0.3T. For some applications, that lower field is acceptable but others, you absolutely need the higher field strength. As a patient, which machine would you pick for your diagnostic imaging?




By dgingerich on 9/24/2012 8:12:01 AM , Rating: 2
There are times when the higher resolution is needed, and times when it is not. Obviously, the numbers aren't mentioned in the article, but there is a likelihood this new design could come close to the high end machines produced today and improve from there, but I can't say for certain. Even if it doesn't, a lot of good medicine was practiced with the older units that didn't have very good resolution. That high end resolution isn't always needed.

I can certainly see a couple nice uses in this magnet design, though. I've never heard of it before, but I can imagine an electric generator design that would be incredibly efficient and useful.


By przemo_li on 9/24/2012 9:01:31 AM , Rating: 2
Second. Cause it would mean that I could get done MRI in days not months. Yes I live in country where for MRI you wait 3-6 months. (Unless you went to the hospital in ambulance)

There are also probably tones of cases where image do not need to be super sensitive, so cheaper equipment would be better, while better equipment could be used for harder cases.


RE: It's cheaper but is it as good?
By aliasfox on 9/24/2012 11:26:38 AM , Rating: 2
It's not necessarily an either-or scenario. A large hospital, for example, could purchase one large, high detail MRI and three or four smaller units so that people who need MRIs to arms/legs/hands/feet can get through the line much more quickly. I'd bet that it's more along these lines:

- Insurance will pay for the $300 cheap MRI, with the understanding that 1/5 cases may need to get a $1000 MRI as well.

- Insurance can only pay for $1000 MRIs.

For 5 scans, the insurance company pays out $2500 in one scenario, $5k for the other.

Alternatively, smaller, more rural, or more financially constrained hospitals now have the opportunity to have an MRI machine where before they didn't. Drive/train hours to the nearest big city, or go to the village/town clinic 30 mins away?


By havoti97 on 9/27/2012 12:13:18 AM , Rating: 2
Let me give some very real scenarios. Suppose condition A is harmless and is easily diagnosed with the cheaper MRI machine while condition B, if not addressed in a timely manner, will kill the patient, ie cancer.

A patient overdoes an exercise routine and feels pain in shoulder. The pain persists despite over the counter pain medication. This doctor thinks it's condition A so he orders an MRI scan on the cheaper, inferior quality scanner. At least that's what his insurance will pay for anyway with his diagnosis.

The scan results come back and does look like condition A. However, condition B may also have that appearance on a cheap scanner, but on a higher quality scanner, the 2 different conditions can be easily differentiated. This could easily lead to misdiagnosis of something that could be treated if caught early.

I know this kind of scenario will be a minority, but we as a society must accept a certain threshold of false negatives if we want to control cost. As of now, we want 100% accurate medicine with dirt cheap cost. The two are almost mutually exclusive with the current technology we have. And guess whose a** is on the line if there is a misdiagnosis. Given the litigious society we live in, which test do you think the doctor who's ordering will order? Which test will you, as a patient, want your doctor to order?


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