Foundations of continuous hyperpolarization explained – new method could pave the way for mobile MRI devices
An international research team led by Dr. Jan-Bernd Hövener from the Medical Physics Section of the Department of Radiology at the Medical Center – University of Freiburg has developed a new, cost-efficient method for magnetic resonance imaging (MRI).
Now the scientists have elucidated the underlying mechanism of the new method in the renowned journal CHEMPHYSCHEM. As a comparison of theoretical simulations with experimental results demonstrates, the basic mechanism is now explained. The method could enable high-resolution MRI images even without expensive high-powered magnets.
The thorough investigation of all relevant factors is an important step toward understanding the new effect, which could lead to the development of new MRI devices for conducting cost-effective chemical analyses as well as precise diagnoses in remote areas – reason enough for CHEMPHYSCHEM to print the study on the inside cover.
Magnetic resonance imaging is a technique that can be used to create cross-sectional images of soft tissue structures inside the body without harmful radiation. MRI devices align a part of the magnetic moments of the hydrogen atoms in the body tissue in an artificial magnetic field and stimulate them with radio-frequency waves, whereupon they return to their original state.
Different signals are sent out depending on the structure and water content of the tissue, forming the basis for calculating the image. The technique usually requires very expensive magnets in order to achieve a sufficiently strong signal. The newly developed continuous hyperpolarization method enables MRI devices to align a much larger part of the hydrogen atoms in lower magnetic fields.
Even in a very weak magnetic field created with a simple battery, the signal is one hundred times stronger than in conventional MRI devices currently in use at hospitals. In addition, thanks to parahydrogen the polarization effect remains available for as long as needed: Normal hydrogen gas, whose atomic nuclei are in a special quantum state, causes the polarization to renew itself after each measurement by means of a chemical exchange reaction, thus enabling multiple images.
In their current study, the Freiburg researchers are searching for the factors responsible for influencing this effect of continuous hyperpolarization: “We’re looking for the optimal conditions for this method. The comparison between theoretical simulation and experimental results shows that the retention time (temperature) and concentration of the parahydrogen play a role as well as the strength of the magnetic field,” says Hövener, who conducts his research at the Medical Physics Section of the Department of Radiology at the Medical Center – University of Freiburg. “It was important to understand
this new effect before speculating about biomedical applications. Fortunately, this is now the case.”
Hövener’s research has attracted great interest: His publication last year in Nature Communications won him second place in the competition for the Klee Foundation Prize of the German Society for Biomedical Engineering (DGBMT), which will be awarded in October at DGBMT’s annual meeting in Hanover.
The German Research Foundation (DFG) is providing the Freiburg medical physicist funding to establish his own research group within the context of the Emmy Noether Program. Hövener has set a clear research goal for the group: “We want to develop new hyperpolarization methods and thus take on the challenges of modern diagnostics. Ultimately, our goal is to develop new methods for identifying and observing diseases earlier, more affordably, and better.”
Title of original publication: Continuous Re-hyperpolarization of Nuclear Spins Using
Parahydrogen: Theory and Experiment
Dr. Jan-Bernd Hövener
Hyperpolarization Group Leader
Medical Physics, Department of Radiology
Medical Center – University of Freiburg
Phone: +49 (0)761 270-93910
Inga Schneider | idw - Informationsdienst Wissenschaft
PET identifies which prostate cancer patients can benefit from salvage radiation treatment
05.12.2017 | Society of Nuclear Medicine and Molecular Imaging
Designing a golden nanopill
01.12.2017 | University of Texas at Austin, Texas Advanced Computing Center
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences