"We have been working with Siemens for over 30 years, developing and applying emerging MRI technologies, and we are excited to continue this great partnership," says Mark Griswold, PhD, professor of radiology at Case Western Reserve and program chair at this year's ISMRM. "We are very proud and excited to be the exclusive partner of Case Western Reserve University to further develop MR Fingerprinting," comments Dr. Christoph Zindel, head of the business line Magnetic Resonance at Siemens Healthcare. "The most innovative applications can only be brought to life through the collaborative efforts of industry and research," says Zindel. "The goal of MR Fingerprinting is to specifically identify and characterize individual tissues and diseases," states Griswold. "But to try to get there, we’ve had to rethink a lot of what we do in MRI."
Planned for characterizing disease tissue earlier and faster
MRF is an innovative, highly versatile and insightful method of measurement, intended to provide non-invasive, user- and scanner-independent quantification of tissue properties. The MRF method is designed to measure a wide range of parameters simultaneously, quantifying many important tissue properties.
Presently, the evaluation of MR images is generally qualitative. In doing so, the properties of the pathology are determined by observing differences in contrast between tissues, instead of being based on absolute measurements of individual tissue properties. Quantitative approaches exist, involving the measurement of diffusion, fat/iron deposits, perfusion or relaxation times, for example. But these sequences often require significant amounts of scan time, and the results vary depending on the scanner and the user. Given the potential low level of variance across a large number of examinations and its expected reproducibility across scanners and in different institutions, MRF could achieve more accurate monitoring and evaluation of patient treatment.
MR Fingerprinting explained
The MRF technique does not acquire traditional clinical images, but instead is designed to gather tissue information based on the signal evolution from each voxel. Acquisition parameters are varied in a pseudorandom fashion, while the signal evolutions are recorded. These are then compared to a database, or "dictionary," to find the entry that best represents the acquired signal evolution of each voxel.
The signal evolutions equate in many ways to "fingerprints" of tissue properties, which, like the identification of human fingerprints in forensics, can only be analyzed by comparing them with a file containing all known fingerprints. The dictionary is equivalent to the database where all the known fingerprints are stored, together with all the information relative to each person. In the forensic case, each fingerprint points to the feature identification of the associated person such as name, height, weight, eye color, date of birth, etc. In the case of MRF, each fingerprint in the dictionary points to the MR related identification features of the associated tissue (such as T1, T2, relative spin density, B0, diffusion, etc.).
The CWRU research team is driving the expansion of this method for a range of different tissue properties. At the same time, the university is working toward expanding the technology to cover additional fields of application. The research team has successfully performed initial tests with brain and prostate tumor patients as well as breast cancer patients with liver metastases. MRF has also been used in cardiac examinations and with patients with multiple sclerosis.
For Siemens, the focus of this collaboration is to improve reproducibility and possibly to extend the procedure to different MR scanners and field strengths. Case Western Reserve uses numerous systems from Siemens, and employs the Magnetom Skyra 3-tesla system for the purposes of this research project.
Work-in-Progress package users confirm potential benefits of method
An initial result of this collaborative process launched in September 2015 is a "Work-in-Progress" (WIP) package, an imaging package for selected Siemens scanners used in research. These WIP packages have been successfully tested since January 2016 at the University Hospital Essen, Germany, and the Medical University of Vienna, Austria, using further Siemens MRI systems.
"The MR Fingerprint technique lets us see more details than the standard imaging process, and has the potential to redefine MRI," confirms Prof. Siegfried Trattnig, of the Center of Excellence for High Field Magnetic Resonance at the Medical University of Vienna, referring to the initial research studies involving patients with malignant brain tumors and low-grade gliomas. "In this way, MRF could help us, as radiologists, to make the paradigm shift from qualitative to quantitative imaging and to incorporate quantitative data into our daily routine." This has the potential to reduce scan times and in turn, bring considerable cost savings in the future.
Related news articles:
- Siemens Profile
About Siemens AG
Siemens AG (Berlin and Munich) is a global technology powerhouse that has stood for engineering excellence, innovation, quality, reliability and internationality for more than 165 years. The company is active in more than 200 countries, focusing on the areas of electrification, automation and digitalization. One of the world's largest producers of energy-efficient, resource-saving technologies, Siemens is No. 1 in offshore wind turbine construction, a leading supplier of gas and steam turbines for power generation, a major provider of power transmission solutions and a pioneer in infrastructure solutions as well as automation, drive and software solutions for industry. The company is also a leading provider of medical imaging equipment - such as computed tomography and magnetic resonance imaging systems - and a leader in laboratory diagnostics as well as clinical IT. In fiscal 2015, which ended on September 30, 2015, Siemens generated revenue of €75.6 billion and net income of €7.4 billion. At the end of September 2015, the company had around 348,000 employees worldwide.
About Case Western Reserve University
Case Western Reserve University is one of the country's leading private research institutions. Located in Cleveland, we offer a unique combination of forward-thinking educational opportunities in an inspiring cultural setting. Our leading-edge faculty engage in teaching and research in a collaborative, hands-on environment. Our nationally recognized programs include arts and sciences, dental medicine, engineering, law, management, medicine, nursing and social work. About 4,900 undergraduate and 5,900 graduate students comprise our student body.