Corbin Nadège, Breton Elodie, de Mathelin Michel, Vappou Jonathan
ICube, University of Strasbourg, CNRS, IHU Strasbourg, ICUBE sc IRCAD,1 place de l'hôpital, 67091, Strasbourg Cedex, France.
MAGMA. 2017 Apr;30(2):203-213. doi: 10.1007/s10334-016-0594-8. Epub 2016 Nov 7.
Magnetic resonance elastography (MRE) requires substantial data processing based on phase image reconstruction, wave enhancement, and inverse problem solving. The objective of this study is to propose a new, fast MRE method based on MR raw data processing, particularly adapted to applications requiring fast MRE measurement or high elastogram update rate.
The proposed method allows measuring tissue elasticity directly from raw data without prior phase image reconstruction and without phase unwrapping. Experimental feasibility is assessed both in a gelatin phantom and in the liver of a porcine model in vivo. Elastograms are reconstructed with the raw MRE method and compared to those obtained using conventional MRE. In a third experiment, changes in elasticity are monitored in real-time in a gelatin phantom during its solidification by using both conventional MRE and raw MRE.
The raw MRE method shows promising results by providing similar elasticity values to the ones obtained with conventional MRE methods while decreasing the number of processing steps and circumventing the delicate step of phase unwrapping. Limitations of the proposed method are the influence of the magnitude on the elastogram and the requirement for a minimum number of phase offsets.
This study demonstrates the feasibility of directly reconstructing elastograms from raw data.
磁共振弹性成像(MRE)需要基于相位图像重建、波增强和反问题求解进行大量数据处理。本研究的目的是提出一种基于磁共振原始数据处理的新型快速MRE方法,特别适用于需要快速MRE测量或高弹性图更新率的应用。
所提出的方法允许直接从原始数据测量组织弹性,无需事先进行相位图像重建和相位展开。在明胶模型和猪模型肝脏体内评估实验可行性。用原始MRE方法重建弹性图,并与使用传统MRE获得的弹性图进行比较。在第三个实验中,通过使用传统MRE和原始MRE实时监测明胶模型凝固过程中的弹性变化。
原始MRE方法通过提供与传统MRE方法获得的弹性值相似的结果,同时减少处理步骤数量并规避相位展开这一棘手步骤,显示出有前景的结果。所提出方法的局限性是幅值对弹性图的影响以及对最小相位偏移数量的要求。
本研究证明了直接从原始数据重建弹性图的可行性。