In May 2017, the Laboratory for Adaptable MRI Technology, funded by Swiss National Science Foundation (PP00P2_170575), took residence at Switzerland Innovation Park Basel Area. The team around Dr. Najat Salameh and Dr. Mathieu Sarracanie aims for nothing less than a paradigm shift in the use of magnetic resonance imaging.
Ever since MRI technology has been used in a medical context, the vast majority of related research has been dedicated to high (and higher) magnetic field strengths. The results perfectly match the requirements of today's radiologists: high spatial resolution in the shortest possible acquisition time. Yet, there are certain drawbacks: The devices are large and heavy, they have to be placed in a dedicated, shielded room, and very strong magnets are necessary. Dr. Najat Salameh compares state-of-the-art MRI scanners to high-performance racing cars: they work great as long as they stay within their environment. Yet, outside of it, they are practically useless. "Today, we basically need to adapt the entire environment to the constraints of the MRI. What we want to do instead is adapt the MR technology to the environment. We want to get it out of the radiology suite and use it in different contexts."
In order to achieve their goals, Dr. Najat Salameh and Dr. Mathieu Sarracanie have returned to Europe after working and researching at the renowned Martinos Center in Boston for five years. They joined the Department for Biomedical Engineering of Basel University and eventually moved in with Park Basel Area in May 2017. Together with PhD student Maksym Yushchenko and Philippe Choquet, a guest researcher from France, they are in the process of setting up their laboratory in Allschwil. Their research is dedicated to making MRI more flexible and reducing the susceptibility artifacts in the generated images. These two main objectives go very well together, as the approach is the same: operating with distinctly lower magnetic field strengths. "Almost every constraint that comes with MRI is tied to the magnetic field", Dr. Mathieu Sarracanie explains. "Therefore, we want to go low!"
At the Lab for Adaptable MRI Technology/Photo: Dr. N. Salameh
While in Boston, Dr. Salameh and Dr. Sarracanie worked with field strengths of 6.5 milliTesla, which is in close neighborhood of fridge magnets. They were able to generate in vivo images of the human brain in around 6 minutes. "The images we obtained were not great, but we showed that it is feasible", says Dr. Sarracanie. At the moment, the efforts focus on field strengths of 20 to 100 milliTesla. Of course, using lower field strengths comes with a price: the sensitivity of the scanner drops rapidly. Therefore, alternative ways to acquire the images are needed. This is one of the tasks that the Laboratory for Adaptable MRI Technology is working on. The possible advantages, on the other hand, are numerous. First of all, smaller magnets can be used if only low field strengths are required. Magnets in today's MRI devices are usually superconductors that consume vast amounts of energy and have to be cooled with liquid helium. A few hundreds of milliTesla can be generated by permanent or resistive magnets. As a consequence, devices might become much smaller, possibly even portable. Moreover, while a lower field strength is equivalent to lower sensitivity, it also creates higher contrast. Dr. Salameh and Dr. Sarracanie consider hundreds of milliTesla might be the "sweet spot" where contrast and sensitivity are at their relative bests.
Portable MRI scanners that could be used in ambulances are only one possible application of this "low field" technology. Eventually, MRI could be used in an operating room, possibly without even interrupting ongoing surgery.
Working on MRI development requires different fields of expertise: magnetics, physics in general, radiofrequency and acquisition electronics as well as quantum physics behind the manipulation of different types of nuclear spins to generate contrast. The Laboratory for Adaptable MRI Technology at Park Basel Area aims to be just that: a unique platform for all those fields. In April, a 3.5-ton magnet will be delivered so a new scanner can be set up. By the end of this summer, Salameh and Sarracanie expect to conduct their first scan with the device. "We have to go fast", says Sarracanie, "as some big companies are starting to show interest in the methods we aim to develop." We wish the team the best of luck and lots of success with their research!