The world’s most powerful MRI machine has started proving its worth, by scanning living human brains. The resulting images give an ultra high resolution glimpse into the brain, which will help us better understand the nature of consciousness and treat neurodegenerative diseases.
Developed by the French Alternative Energies and Atomic Energy Commission (CEA), the Iseult MRI machine packs a magnetic field strength of 11.7 Teslas (T). By comparison, conventional MRI machines in wide use in hospitals today are usually 1.5 or at most 3 T.
The main benefit of that extra power is that much higher resolution images of the brain can be taken, much quicker. In just four minutes, Iseult can capture images down to 0.2 mm (0.008 in) of brain tissue horizontally, in 'slices' just 1-mm (0.04-in) thick. That volume is the equivalent of a few thousand neurons at a time.
For conventional MRI machines to take images of this resolution, patients would need to lie perfectly still for more than two hours – the slightest movement would blur the shot. That of course just isn’t feasible.
Also boosting comfort is the 90-cm (35.4-in) wide 'hole' for patients to stick their heads in. That might not seem like a huge increase over the usual 60-to-70 cm (23.6-to-27.6 in), but the extra headroom can help make the experience less claustrophobic.
Iseult was tested a few years ago on pumpkins, but now it’s scanned its first human brains, belonging to 20 healthy volunteers. The stunning images demonstrate the potential for the new MRI technology to reveal previously unattainable information about how the brain works, including how it encodes mental representations, and which neuronal signatures are associated with consciousness itself.
Besides those existential questions, Iseult should also help scientists understand, diagnose and treat neurodegenerative diseases like Alzheimer’s and Parkinson’s. It should be able to detect chemical signatures that are usually too weak to be seen with regular MRI scans, including molecules like glucose and glutamate, which are involved in brain metabolism and disorders of which can be involved in conditions like gliomas and neurodegeneration. It will also be able to track the distribution of lithium in the brain, which is used to treat bipolar disorders.
Thanks to its complexity, Iseult is far larger than other MRI machines. It measures 5 m (16.4 ft) long and wide, weighs 132 tons and is made with 182 km (113 miles) of superconducting wires. To keep the magnets cooled to the required -271.35 °C (-456.43 °F) takes some 7,500 liters (1,981 gallons) of liquid helium. That size, complexity and no doubt cost might limit where the Iseult MRI machine can be used, but hopefully it will be beneficial enough to go into service in some specialty facilities soon.
The team discusses the tech in the video below.
Source: CEA
