Sub-nanosecond phase coherence wins Spectrum a place in mini-MRI machine

Update: December 8, 2023

Start-up Neoscan is behind the machine. “We we used this route of standard cards providing a platform to run our software on. This meant that we could focus our skills on the software development,” said Neoscan founder Stefan Roell.

Arbitrary waveform generator and signal acquisition hardware was required, with a particular need to maintain sub-nanosecond phase coherence amongst 64MHz signals.

“During the research phase, it was hard to determine this from the specifications of the cards provided by the various suppliers that we contacted, as it is a rather unusual level of detail,” according to Roell. “However, Spectrum was outstanding in helping us with technical support, both in the specification of the cards to use and again during the implementation. A rival proposal took weeks longer to arrive, and they had not made the effort to understand the detail of our project.”

In the end, M4i.6620-x8 and M2p.6546-x4 AWGs and a M2p.5968-x4 digitiser were selected, plus Spectrum’s SCAPP software drivers that allow data to be processed on GPUs, rather than CPUs.

Neoscan’s MRI has been designed to fit through standard doorways, and not to need re-enforced floors.

Being limited to patients up to two years old allowed the bore of the machine to be shrunk to 300mm from the standard 600mm.

Neoscan magnet assembly

Further size reduction came form a novel dry (non-liquid helium) electromagnet that generates the required internal 1.5T field using an inner cylindrical 2.5T magnet, surrounded by an outer cylindrical magnet that actively cancels external fields “so that there are no stray magnetic field left beyond about 1m from the device’s cover”, according to Spectrum.

The result is a 1.7 x 1.5 x 1,1m scanner that weighs 2 tonnes and has a 10m2 installation footprint – contrasted by Spectrum with 8 tonnes and ~40m2 plus helium for a typical MRI.