Over the last decade MR diffusion imaging has evolved into an immensely useful tool to assess stroke, tissue fiber architecture, and characteristic tissue water diffusion. Nevertheless, compared with other commonly applied MR image contrasts, state-of-the art MR diffusion imaging exhibits significant deficiencies. The widely used 2D single-shot diffusion imaging techniques tend to produce images of inferior quality, often suffering from distorted image geometry and poor signal-to-noise ratio (SNR). In particular, distorted image geometries preclude direct comparisons with images of different contrast or different imaging modalities. In the quest for better MR diffusion imaging pulse sequences, numerous approaches have been suggested, like reduced field-of-view imaging, line and slab scan diffusion imaging (LSDI and SSDI), single-shot parallel diffusion imaging, and segmented multi-shot diffusion imaging. While all of these methods reduce to some extent the excessive distortions often present in diffusion images, such improvements invariably come at the expense of increased scan time and/or reduced SNR. In the present work, the main incentive is to greatly alleviate the SNR problem by extending the image acquisition to 3D. Until now, this extension to 3D has been hampered by prolonged scan times and proneness for motion artifacts. The proposed research introduces novel methods, which promise to overcome these disadvantages.
The specific aims are: 1) To develop SNR-neutral parallelization in 3D for the typically slower, but very artifact- resistant LSDI and SSDI sequences. 2) To parallelize multi-shot segmented 2D along the third dimension and to develop 3D diffusion imaging with 3D navigator correction of motion-related phase errors. 3) To develop novel acceleration schemes to keep 3D diffusion imaging scan times within practical limits, while also reducing distortion artifacts. 4) To test these developments in phantoms, in normal volunteers, and in neuroepithelial tumor patients, who undergo clinical scans with the purpose of surgical treatment planning.
The capability of magnetic resonance imaging to measure and image molecular diffusion has provided a new source of image contrast and has proven extremely useful in assessing stroke-related damage and the fiber architecture of nerves and muscles. While 3D diffusion imaging would present significant advantages over 2D imaging, it has up to now been impeded by technical problems, such as long acquisition times and motion artifacts. The present application aims at solving these problems, to enable robust and practical 3D diffusion imaging.
| Aksit Ciris, Pelin; Chiou, Jr-Yuan George; Glazer, Daniel I et al. (2018) Accelerated Segmented Diffusion-Weighted Prostate Imaging for Higher Resolution, Higher Geometric Fidelity, and Multi-b Perfusion Estimation. Invest Radiol : |
| Zhang, Shelley HuaLei; Maier, Stephan E; Panych, Lawrence P (2018) Improved spatial localization in magnetic resonance spectroscopic imaging with two-dimensional PSF-Choice encoding. J Magn Reson 290:18-28 |
| Chao, Tzu-Cheng; Chiou, Jr-Yuan George; Maier, Stephan E et al. (2017) Fast diffusion imaging with high angular resolution. Magn Reson Med 77:696-706 |
| Mulkern, Robert V; Balasubramanian, Mukund; Maier, Stephan E (2017) On the perils of multiexponential fitting of diffusion MR data. J Magn Reson Imaging 45:1545-1547 |
| Preiswerk, Frank; Toews, Matthew; Cheng, Cheng-Chieh et al. (2017) Hybrid MRI-Ultrasound acquisitions, and scannerless real-time imaging. Magn Reson Med 78:897-908 |
| Ciris, Pelin Aksit; Cheng, Cheng-Chieh; Mei, Chang-Sheng et al. (2017) Dual-Pathway sequences for MR thermometry: When and where to use them. Magn Reson Med 77:1193-1200 |
| Mitsouras, Dimitris; Lee, Thomas C; Liacouras, Peter et al. (2017) Three-dimensional printing of MRI-visible phantoms and MR image-guided therapy simulation. Magn Reson Med 77:613-622 |
| Mitsouras, Dimitris; Mulkern, Robert V; Maier, Stephan E (2016) Multicomponent T2 relaxation studies of the avian egg. Magn Reson Med 75:2156-64 |
| Fedorov, Andriy; Tuncali, Kemal; Panych, Lawrence P et al. (2016) Segmented diffusion-weighted imaging of the prostate: Application to transperineal in-bore 3T MR image-guided targeted biopsy. Magn Reson Imaging 34:1146-54 |
| Cheng, Cheng-Chieh; Mei, Chang-Sheng; Duryea, Jeffrey et al. (2016) Dual-pathway multi-echo sequence for simultaneous frequency and T2 mapping. J Magn Reson 265:177-87 |
Showing the most recent 10 out of 19 publications
