A new frontier
Magnetic Resonance diagnostics is at the frontier of a paradigm shift. Until now, an MR image has been a mixture of weighted tissue properties, provided by sequential, repetitive data-acquisition with fixed parameters. Diagnostic evaluation has been purely qualitative, and highly dependent on system parameters. Magnetic Resonance Fingerprinting1 (MRF) makes it possible to glean quantitative information from scans that enable decisions based on digital tissue data, not visual impressions. The target anatomy can be described numerically instead of visually.
What is MRF?
Magnetic Resonance Fingerprinting (MRF)1 uses quantitative information to generate a more precise understanding of a patient’s condition. Quantitative MRF offers enormous potential to improve tissue differentiation and enable less invasive diagnostics. Based on reliable, absolute numbers, MRF data could increase objective comparisons in follow-up studies. Ultimately, aided by artificial intelligence (AI), quantitative measurements will lead to more personalized treatments. MR Fingerprinting is at the frontier of a new dimension in quantitative imaging.
MR Fingerprinting in a nutshell
Features & Benefits
MRF Acquisition – it’s robust and rapid
MR Fingerprinting generates reliable, quantitative multi-parametric maps with high reproducibility that can lay the groundwork for more accurate diagnosis.
MRF acquisition employs an innovative, pseudo-random variation of scan parameters, such as flip angle (FA), repetition time (TR), echo-time (TE), or readout trajectory, to extract multiple quantitative tissue parameters from a single scan. By varying these parameters, tissues create unique signal evolutions of data or “fingerprints,” which reflect the composition of the scanned tissue. MRF utilizes a spiral sampling trajectory, which drastically under-samples the acquired data. This results in a fast and efficient acquisition, while preserving spatial and temporal data integrity.
MRF Dictionary – it’s precise and efficient
MR Fingerprinting intends to acquire quantitative maps to accurately measure tissue properties, and describe the target anatomy numerically instead of visually.
Every MRF acquisition sequence has its own Dictionary that is calculated before scanning. The Dictionary is a database of possible unique signal evolutions, or fingerprints. For example, the three properties, T1, T2, and B1, can lead to a Dictionary with over 700,000 entries. A pattern matching process compares the fingerprints with the Dictionary. When there is a match, the properties of this fingerprint are assigned to a map. This process is repeated sequentially until all fingerprints have a corresponding property, creating a 1:1 map.
MRF Analyzer – it’s data, visualized
The objective of MR Fingerprinting is to generate robust, quantitative multi-parametric maps with high reproducibility that are able to measure absolute values.
The Analyzer2 simultaneously analyzes all quantitative data from MRF parameter maps, conventional parameter maps, and anatomical MR data. The dependency between two parameters is visualized by a scatter plot for the analysis of the relationship of measured
quantitative MRF parameters (such as T1 or T2 values), and conventional quantitative data (such as ADC values). The plot displays the values of one parameter over a second parameter across all voxels of the measured volume. This represents distinct areas characterizing different tissue types.
Clinical study: What can MRF contribute to potentially improve therapy planning? What are the relevant regions for targeted biopsy?
LOW GRADE (WHO II) ASTROCYTOMA
Images courtesy Prof. Siegfried Trattnig, AKH Vienna
Clinical study: Lesion characterization, 68 year-old male, headache for more than 10 days
HIGH GRADE (WHO IV) GLIOMA
Images courtesy Prof. Meiyung Wang, Henan Provincial People‘s Hospital, PR China
Clinical study: Evaluation of diffuse lesions in MS
48 year old male patient under treatment for Multiple Sclerosis
Images courtesy Fernanda Rueda-Lopes and Cinthia Chaves, DASA, RJ, Brazil
Articles and Talks
1Magnetic Resonance Fingerprinting is 510(k) pending. It is not commercially available in all countries. Due to regulatory reasons the future availability cannot be guaranteed.
2For research use only. Not for clinical use
37T system mentioned herein is an investigational device. The product is still under development and not commercially available yet. Its future availability cannot be ensured.