An optimised framework for reconstructing and processing MR phase images

作者：Chen Zhaolin^*; Johnston Leigh A; Kwon Dae Hyuk; Oh Se Hong; Cho Zang Hee; Egan Gary F

来源：NeuroImage, 2010, 49(2): 1289-1300.

DOI：10.1016/j.neuroimage.2009.09.071

• MR phase image
• Tissue susceptibility
• Accelerated parallel MRI
• Phase optimised image reconstruction
• Background phase removal
• 7T MRI

Phase contrast imaging holds great potential for in vivo biodistribution studies of paramagnetic molecules and materials. However, in Vivo quantification of iron storage and other paramagnetic materials requires improvements in reconstruction and processing of MR complex images. To achieve this, we have developed a framework including (i) an optimal coil sensitivity smoothing filter for phase imaging determined at the maximal signal to noise ratio, (ii) a phase optimised and a complex image optimised reconstruction approach, and (iii) a magnitude and phase correlation test criterion to determine the low pass filter parameter for background phase removal. The method has been evaluated using 3T and 7T MRI data containing cortical regions, the basal ganglia including the caudate, and the midbrain including the substantia nigra. The optimised reconstruction improves phase image contrast and noise Suppression compared with conventional reconstruction approaches, and the correlation test criterion provides an objective method for separation of the local phase signal from the background phase measurements. Phase values of several brain regions of interest have been calculated, including gray matter (-1.23 Hz at 7T and -0.55 Hz at 3T), caudate (-3.8 Hz at 7T), and the substantia nigra (-6.2 Hz at 7T).

• 出版日期2010-1-15