Field-Cycling Add-On for Clinical MRI Scanners

Magnetic Resonance Imaging (MRI) is a non-invasive method for producing highly detailed images of the human body. It is used every day in hospitals around the world, and is particularly good at highlighting diseased tissue (e.g. cancer). It works by placing the patient into a very strong magnetic field. This causes the magnetic hydrogen atoms in water molecules to line up along the magnetic field. When a burst of weak radiowaves is applied, some of the energy is absorbed and this causes the hydrogen atoms to flip round in the magnetic field. After a time delay (called the "T1 relaxation time") the atoms revert to their original orientations and re-emit the radiowaves in the form of a "signal", which is picked up by the scanner. The process is repeated hundreds of times over the course of a few minutes, and the signals are then analysed by computer to produce an image (picture) of where the signals came from in the body. The delay time (T1) between receiving and re-emitting radiowaves is very sensitive to the type of tissue (e.g. the T1 of kidney is different to the T1 of leg muscle) and also changes if the tissue is diseased (brain tumour has a longer T1 than normal brain). Therefore, the T1 relaxation time is used to introduce "contrast" into MR images, which radiologists use to diagnose disease.
Through experiments done outside the body on small tissue samples, biomedical scientists have discovered that the T1 relaxation time also depends strongly on the strength of the magnetic field used (thus, the T1 of liver is longer when measured in a 1.5 Tesla magnet than it is at 1.0 Tesla). Furthermore, the way in which T1 changes with magnetic field is different in different tissues, and can also change in disease. The manner in which T1 changes as a function of magnetic field is called "T1 dispersion" and a graph of T1 versus magnetic field strength is called a T1 dispersion curve.
T1 dispersion could be of great use in diagnosing disease, but hospital MRI scanners cannot measure T1 dispersion, because each scanner operates at a single magnetic field strength (e.g. 1.5 Tesla or 3.0 Tesla) and cannot be changed. In a previous research project at the University of Aberdeen, we have shown that it is possible to design and build special MRI scanners in which the magnetic field applied to the patient can be changed very rapidly, while the scan is in progress. This method is called "Fast Field-Cycling MRI" (FFC-MRI). We have produced methods of measuring T1 dispersion curves, linked to MR images, and our research has also shown the potential for improving diagnosis, in diseases as diverse as osteoarthritis and deep-vein thrombosis. The potential also exists to use FFC-MRI to detect diseases which involve protein malformation and malfunction, such as Parkinson's disease, Alzheimer's disease, and many more.
At the moment, only two human-sized FFC-MRI scanners exist, both of them in our research laboratories. Hospitals cannot buy FFC-MRI scanners, because the companies that sell scanners do not yet build them for sale. However, there is a potential way in which some types of hospital MRI scanner (called "open" scanners) could be retro-fitted with additional hardware and software to allow them to perform FFC-MRI scans, and therefore enhance diagnosis of their patients. The upgrade "kit" includes additional magnet hardware that can be moved in or out, depending on whether FFC-MRI or standard MRI is being used, together with control and analysis software.
The purpose of this project is to create preliminary designs for add-on hardware and software for FFC-MRI, and to develop the technology so that it can be demonstrated to companies which manufacture MRI scanners. The hope is that the technology would then be manufactured by the medical imaging industry and would then be purchased by hospitals and research institutes, making FFC-MRI much more widely available.

Who will benefit from this research?
* Large medical imaging companies which manufacture and supply MRI systems.
* Smaller companies (SMEs) supplying components to medical imaging companies.
* Hospital radiology departments.
* Patients with a range of medical conditions.
* Universities and research institutes conducting research into MRI.
* The food and drink industry.
* Veterinary medicine.
* Research staff working on the project.

How will the beneficiaries benefit from this research?
The research has the potential to bring Fast Field-Cycling (FFC) MRI to a wide range of users. One result is that the diagnostic advantages of this new method will be available in a large number of hospitals, directly benefitting health service providers due to faster diagnosis and shorter patient stays. Patients will benefit for the same reasons, and as a result the research will contribute to the health and wellbeing of the general population.
Universities and research institutes will benefit from having the ability to conduct research into FFC-MRI - an area which has hitherto only been open to the small number of research groups with the ability and facilities to build their own equipment. This will also expand the range of training offered to students and researchers in these institutions.
Manufacturers of MRI systems will benefit from increased sales of open-geometry MRI systems which are capable of being upgraded by the add-on field-cycling hardware. Likewise, the companies manufacturing the add-on hardware will benefit from the sales of this equipment, and also from the increased exposure in the market that association with the novel hardware will bring.
The food and drink industry will benefit from the ability of research institutes which have the FFC-MRI facility using the field-cycling technique to test products for possible adulteration. We have already begun to explore the use of field-cycled relaxometry to differentiate between real and counterfeit Scotch Whisky, working with a body representing the industry.
Veterinary medicine will benefit from the enhanced diagnostic procedures available in animal imaging centres which adopt the FFC-MRI technology. Human endeavours involving animals will also benefit from improved animal health. An example is horse racing - there is already a significant number of equine imaging centres using purpose-designed MRI scanners, many of which could be upgraded for FFC-MRI using the add-on technology.
Research staff working on the project will benefit from exposure to commercialisation and market research methodology, and from close contacts with small, medium and large industrial companies. The project will enhance their knowledge, and will make them more employable, in industry as well as academia.

When will the benefits arise?
The research staff will benefit throughout the period of the project, and after it has finished due to the extra skills and knowledge gained. MRI manufacturers which license the technology will benefit as soon as they are able to bring the product to market, typically 1-2 years after the project end. Likewise, users of the technology will benefit once the add-on technology is installed on their scanner, 1-2 years after completion of the project. Indirect beneficiaries such as hospital patients will start to benefit as soon as the technology is installed in hospitals and research institutes, and the benefit to these communities will increase as the numbers of FFC-MRI upgraded scanners increases over the following 1-2 years. With more scanners thus equipped, knowledge about their benefits and optimum use will spread among the potential user community, further increasing the number of units sold, to the benefit of manufacturers, users and society at large.