For Thomas and his colleagues at the Spinoza Center in Amsterdam, there was a lot to celebrate in December 2024. And not just because of the holidays, but also because the first 7 Tesla MRI scanner was clinically certified. This means that health insurers may reimburse treatment with the powerful scanner. A milestone for doctors and researchers who specialize in complex neurological diseases, brain disorders or cancer.
Super magnets
“MRI scanners are essentially super magnets,” Thomas explains. “They use very strong magnetic fields. The Tesla is a unit that expresses the strength of such a magnetic field. The higher the number, the stronger the signal.” This last aspect is particularly important, Thomas explains. “With a stronger signal, you can scan faster and make sharper scans in the same time. Most hospitals use MRI scanners of 1.5 or 3 Tesla. These can also make sharp images, but it takes a long time. This is not pleasant for patients. With a magnetic field that is more than four times as strong as a conventional scanner, the 7 Tesla MRI offers an unprecedentedly high image resolution and level of detail. This allows structures and functions in the brain to be visualized with razor-sharp clarity, including any abnormalities therein.”
The 7 Tesla scanner makes it possible to treat Parkinson's better and to examine the chemical composition of a tumor in detail. "We can even visualize white matter tracts in the brain. This was impossible with other scanning techniques," Thomas says enthusiastically.
Challenges
The challenge is to create a scanner that works quieter and faster, but still maintains the desired high resolution. Thomas: “We know that it is possible to let the coils work at lower frequencies, but the whole process then takes longer. What we do now is exactly the opposite. We do not scan slower, but much faster so that the tones become so high that we can no longer hear them. People do not hear anything above 20 kilohertz. In short: we make the scanner quieter by using the properties of human hearing. That sounds simple, but it involves a lot of technical developments.”
Thomas continues: “What inspires me is that our work delivers tangible results directly. For example, during a study of deep brain stimulation in Parkinson’s patients, the doctor was able to place the electrodes more accurately thanks to the improved 7 Tesla images. This made the treatment less stressful for the patients. There was even a woman who came back especially to thank us!”
From a drill to soft tapping
After four years of research, Thomas and his colleagues have succeeded in reducing the noise level from 120 to 67 decibels. “The sound has been reduced from a rock concert to soft tapping,” Thomas laughs. In addition, Thomas and his colleagues are working on autonomous MRI scanners that perform scans without the intervention of medical personnel. “These are 1.5 Tesla scanners that are user-friendly, fast and quiet,” says Thomas. “Thanks to smart techniques, the device helps the patient to take a seat in the MRI scanner independently. It is no longer necessary to travel to the hospital for a simple scan. This is pleasant for the patient and at the same time relieves the burden on hospitals. There is already an autonomous scanner in a nursing home and the first results are positive.”
Protect
A specific problem that the young researcher had to solve was protecting sensitive equipment from the influence of external signals. Thomas: “MRI scanners use Faraday cage technology to keep noise out. The EMC filters that we used in the beginning turned out to be insufficiently resistant to inductive peaks from the new technology, which caused them to get damaged time and time again. My colleagues and I spent years looking for filters that could handle the high pressure, but they always broke after one or two scans.”
Unexpected angle
The solution came from an unexpected angle. “In addition to my work at the hospital, I also have my own company and for that I went to the Medical Electronics event of FHI. There I ran into Danny Langbroek from Elincom Electronics and we got to talking. I told him about the filter problem and he offered to help me find a solution.”
Thomas continues: “A ready-made filter with the specifications I needed turned out not to exist. In total, Danny and I went back and forth for a year, until Elincom finally had a custom filter made. To be honest, I didn’t think it was possible anymore, but we did it. So far, no filter has broken.”
Although Thomas and his colleagues have achieved important goals, their project is never finished. “We work with hundreds of people to improve MRI scanners. My research is just a small part of the whole. It is precisely by working together that we achieve technical milestones that have a major impact on the well-being of the patient.”
Register
During the Medical Electronics event on January 30 in Nijmegen, Thomas and Danny will be on stage together to talk about their experiences. Register for the event and lecture for free via the website.
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