Final Report Summary - THE MR CHALLENGE (Expanding the horizons of magnetic resonance in sensitivity, imaging resolution, and availability)
The "MR Challenge" project focuses on the development and application of new methodologies in the field of magnetic resonance (MR). Magnetic resonance involves the inspection of tiny magnetic species that exist in many materials, such as certain nuclei or unpaired electrons, using a combination of static and alternating magnetic fields. These magnetic species can provide us with a wealth of information about the structure of molecules, their dynamics, and the environmental conditions they are subjected to. Therefore, magnetic resonance has become one of the most versatile fields of science and technology, with applications ranging from chemical structure determination to medical imaging and quantum information processing. From a scientific point of view, magnetic resonance has already been the main focus of at least six Nobel prizes in physics, chemistry, and medicine. From an industrial point of view, magnetic resonance is a multibillion-dollar industry aimed at a wide range of medical and chemical applications.
Despite the fact that magnetic resonance was discovered more than 60 years ago, and that magnetic resonance imaging is more than 30 years old, there is still “plenty of room at the bottom” for new methodologies, approaches, and applications. For example, magnetic resonance is known to be a very insensitive technique that requires relatively large amounts of material for spectroscopic evaluation. During the "MR Challenge" project, we have significantly improved the sensitivity of this technique without sacrificing its generic nature. In our recent work, we managed to improve the detection sensitivity of electron spin resonance (ESR), which is a common branch of magnetic resonance, reducing the quantity of electron spins required from ~10^8-10^9 to ~10^3 spins. Another aspect that limits the capability of MR relates to the fact that magnetic resonance imaging has a relatively low spatial resolution in the order of several microns, which is not sufficient for many modern applications. Here also, through the development of new methodological tools, we have improved ESR imaging resolution from a few microns down to ~400 nm. Yet another problematic aspect of magnetic resonance is its relatively high complexity and cost. This is mainly due to the use of large static magnets. One aspect of this problem was addressed in a collaborative project we carried out with a medical device company, in which we developed a unique self-contained magnetic resonance imaging (MRI) probe for combined ultrasound/MRI imaging of the prostate gland. This probe is made of a small permanent magnet, a transmit/receive radiofrequency coil, and imaging gradient coils. It is intended for endorectal use to aid in the diagnosis of prostate cancer by directing biopsy sampling to the most suspicious regions in the prostate. Another small medially-oriented probe that we have recently developed is intended for a completely different (but very useful) clinical application. It uses ESR measurements of intact teeth to evaluate with relatively high accuracy the amount of ionizing radiation dose a person was exposed to.
Despite the fact that magnetic resonance was discovered more than 60 years ago, and that magnetic resonance imaging is more than 30 years old, there is still “plenty of room at the bottom” for new methodologies, approaches, and applications. For example, magnetic resonance is known to be a very insensitive technique that requires relatively large amounts of material for spectroscopic evaluation. During the "MR Challenge" project, we have significantly improved the sensitivity of this technique without sacrificing its generic nature. In our recent work, we managed to improve the detection sensitivity of electron spin resonance (ESR), which is a common branch of magnetic resonance, reducing the quantity of electron spins required from ~10^8-10^9 to ~10^3 spins. Another aspect that limits the capability of MR relates to the fact that magnetic resonance imaging has a relatively low spatial resolution in the order of several microns, which is not sufficient for many modern applications. Here also, through the development of new methodological tools, we have improved ESR imaging resolution from a few microns down to ~400 nm. Yet another problematic aspect of magnetic resonance is its relatively high complexity and cost. This is mainly due to the use of large static magnets. One aspect of this problem was addressed in a collaborative project we carried out with a medical device company, in which we developed a unique self-contained magnetic resonance imaging (MRI) probe for combined ultrasound/MRI imaging of the prostate gland. This probe is made of a small permanent magnet, a transmit/receive radiofrequency coil, and imaging gradient coils. It is intended for endorectal use to aid in the diagnosis of prostate cancer by directing biopsy sampling to the most suspicious regions in the prostate. Another small medially-oriented probe that we have recently developed is intended for a completely different (but very useful) clinical application. It uses ESR measurements of intact teeth to evaluate with relatively high accuracy the amount of ionizing radiation dose a person was exposed to.