Low Res MRI

An image displaying the partialy assembled MRI on a table with the magnet-insertion tool next to it

As an institution, one of our goals is to contribute towards long-term, multi-year projects. Examples of long-term projects include the famous solar car at Eindhoven or the Delft hyperloop projects. At LPL, we are developing a small, low-field (low-resolution) magnetic resonance imaging (MRI) scanner. Such an MRI scanner could potentially be deployed in places where a regular MRI is too costly or too large, such as a doctors office or a hospital in a developing country. This technology is not new, but still needs improvements, both in construction and data recording/processing, before it is ready to be deployed. The magnet Zach built will be used to further develop the technology.

To kick off the project Zach Meredith produced the core of any MRI: the magnet. Instead of an electromagnet, as found in common MRI machines, this design uses a permanent magnet arrangement. As an open science project, this involved looking into the available documentation from the sustainable MRI Lab, interpreting it and, at times, making adjustments based on our materials and machines.

An MRI needs a homogenous magnetic field in center of the device. For a permanent magnet setup, this can be created using a Halbach array. To hold the array in place rings were 3D printed from tough PLA. This required several iterations of 3D design and tweaking. For assembly, each 12x12mm magnet is tested, polarity oriented and carefully inserted into the 3D printed ring. An acrylic cover plate twist locks in place to secure the magnets. With all nine rings - 396 powerful magnets - filled, the rings are stacked to form the complete magnet.

The end product here was then the start of the Experiment Design course 2024/2025, where student groups developed additional components for this MRI.

Additional development

An image displaying the coil build by experimental design to be inserted into the MRI. It is a 3D printed tube with copper lined into it.

The project was further devoloped in the course Experimental Design given by Sanli Faez in 2024-2025. At the beginning of the course, the set-up for the MRI existed but was yet to be tested or a signal measured. Therefore, the class was split up into 5 group of 3, with each group having a sub-question, this enabled groups to work in parallel with their own focus, but all ultimately contribute towards a larger project. Sub-questions included; producing and detecting RF signals, building gradient coils and measuring and monitoring the magnetic field.

These projects are varied in both their goals and their needs from LPL. We were able to support students by making our physical space available to them to work on their prototypes but also offering feedback on their approaches. This uses a quite some resources, but the end results are functional prototype with a clear scientific and social purpose. At the end of the course, a symposium is organized to share the projects the students have developed with the wider academic community within the UU. This is both a moment to evaluate the projects but also come together as a community to think about future projects.

MRIs work through the manipulation of magnetic fields. One of the ways this can be done is through generating magnetic fields in specific shapes using copper wiring. The patterns you see on the 3D prints relate to changing the magnetic field in the X,Y,Z orientations (hence three subcomponents). These 3D prints were challenging to make due to their size and the difficulties in having a shallow relief. One interesting solution was the use of water-soluble supports which could be removed without damaging the print.

If you feel inspired, or just want to take a better look at the project, again, feel free visit our official GitHub page with further information on the OSII-Mini. A link is provided at the bottom of this page.