Quantitative MRI

A very fast 3D method

We developed an MRI pulse sequence that fairly rapidly gathers a lot of information about the imaged object. It is a multi-pathway multi-echo (MPME) pulse sequence, and an example is shown in Fig. 1. Note how images from different magnetization pathways have very different tissue contrasts, and how this contrast changes with echo time (TE):

 

 

Fig.1

Quantitative MRI

We then use neural networks as 'contrast translators', to convert these information-rich MPME datasets into quantitative contrasts (T1 and T2 maps) as well as well-known traditional contrasts (for example, FLAIR, MPRAGE,  T2-weighted, T1-weighted):

 

 

Fig. 2

3D translated contrasts

The overall goal of this project is to gather enough information in one relatively-short MPME 3D scan (roughly 5-7 min) to possibly replace a whole brain MRI exams.

 

A reasonably-fast, readily available 2D method

Most quantitative imaging methods, including our MPME method above, involve special MRI pulse sequences that are not readily available on clinical scanners and/or that may require long scan times. For convenience, we developed a method based on the readily-available multi-shot spin-echo (SE) echo-planar imaging (EPI) sequence. For example, in Fig. 3, results are shown from three neuroradiology patients (scan time = 4min20s, 192×192 matrix size, 24×24 cm2 FOV, 10 slices, 2 mm thickness and 14 mm gap). Two of the ten acquired slices are displayed here for each patient. If interested, an imaging protocol and associated reconstruction code should become available under the 'Resources' tab before the end of 2022.

 

 

Fig. 3

SE EPI QUANTITATIVE MRI RESULTS

 

Publications

  1. Madore B, Jerosch-Herold M, Chiou J-Y, Cheng C-C, Guenette JP, and Mihai GA. “A relaxometry method that emphasizes practicality and availability.” Accepted for publication in Magn Reson Med.
  2. Cheng C-C, Preiswerk F, and Madore B. 2020. “Multi-pathway multi-echo acquisition and neural contrast translation to generate a variety of quantitative and qualitative image contrasts. Finalist in the 2020 ISMRM Young Investigators Rabi Award Competition.” Magn Reson Med, 83, Pp. 2310-21.
  3. Cheng C-C, Hoge WS, Kuo TH, Preiswerk F, Madore B. Multi-pathway multi-echo (MPME) imaging: all main MR parameters mapped based on a single 3D scan. Magn Reson Med 2019; 81: 1699-1713.
  4. P Aksit Ciris, C-C Cheng, C-S Mei, LP Panych, B Madore. “Dual-Pathway sequences for MR thermometry: When and where to use them.” Mag Reson Med 2017; 77:1193–1200.
  5. C-C Cheng, C-S Mei, J Duryea, H-W Chung, T-C Chao, LP Panych, B Madore. “Dual-pathway multi-echo sequence for simultaneous frequency and T2 mapping.” J Magn Reson 2016; 265:177-87.
  6. C-S Mei, R Chu, WS Hoge, LP Panych, B Madore. “Accurate field mapping in the presence of B0 inhomogeneities, applied to MR thermometry.” Mag Reson Med 2015; 73:2142-51.
  7. B Madore, LP Panych, C-S Mei, J Yuan, R Chu. “Multipathway sequences for MR thermometry.” Magn Reson Med 2011; 66:658-68.

 

Abstracts (last 5 years)

  1. Madore B, Jerosch-Herold M, Chiou Jr-y, Cheng C-C, Mukundan S, Guenette J, and Mihai G. 2022. “Practical and readily-available relaxometry method.” Proceedings of the International Society of Magnetic Resonance in Medicine. London, UK.
  2. Cheng C-C, Guenette J, and Madore B. 2021. “Early results from a patient study aimed at testing a quantitative and synthetic brain MRI method, for abbreviated neuro protocols.” Proceedings of the International Society of Magnetic Resonance in Medicine. Virtual Meeting.
  3. Cheng C-C, Preiswerk F, and Madore B. 2020. “Multi-pathway multi-echo acquisition and contrast translation to generate a variety of quantitative and qualitative image contrasts. Finalist for the YIA Rabi award.” Proceedings of the International Society of Magnetic Resonance in Medicine. Virtual Meeting.
  4. C-C Cheng, F Preiswerk, and B Madore. 2019. “Quantitative and synthetic MRI using a Multi-Pathway Multi-Echo (MPME) acquisition followed by machine-learning contrast translation.” Proceedings of the International Society of Magnetic Resonance in Medicine. Montréal, Québec, Canada.
  5. C-C Cheng, WS Hoge, T-H Kuo, and B Madore. “Quantitative MRI method, a multi-pathway multi-echo approach.” Proceedings of the International Society of Magnetic Resonance in Medicine 2017. Honolulu, USA, p. 5044.