First MRI of the Brain
Scientists from Los Alamos National Labs in New Mexico have recently taken the first MRI (Magnetic Resonance Imaging) scan of the human brain.
The method they used is called "ultra-low field MRI," where the magnetic field is about 100 times weaker than that used in a normal MRI. However, it's still about the same strength as the Earth's magnetic field.
Los Alamos researcher Vadim Zotev had the honor of being the first person to have their brain scanned by the MRI. Like in conventional MRIs, the new technology images the brain by detecting how hydrogen atoms respond to magnetic fields.
The first ultra-low field MRI scan was demonstrated by John Clarke in 2004 at the University of California-Berkley, although that device could only image objects smaller than the size of a baseball. While Clarke's device used only one sensor, Zotev's new MRI uses seven of the sensors, affectionately named "SQUIDS" (superconducting quantum interference devices).
Besides its ability to image the brain, ultra-low field MRI has several advantages compared with conventional MRI. Because it doesn't require high-strength magnetic fields, it's significantly less expensive. The most expensive part, Zotev explained, is a $20,000 liquid helium cryostat used for cooling the SQUIDS.
Another advantage is convenience. While MRI machines today require the patient to lie in a cramped tube, ultra-low field MRI can occur in a more open environment, even allowing surgical tools and robots to be involved.
Finally, ultra-low field MRI may be harmless to patients who have metal implants, whereas the strong magnetic fields in conventional MRI can cause metal implants to heat up and damage surrounding tissue. However, the researchers are still testing the safety of this possibility.
Because the new machine can detect small magnetic fields associated with electrical activity in the brain, it could be used by physicians to identify areas of the brain with abnormal activity, such as in epilepsy, among other applications.
via: New Scientist