Dynamic shim updating (DSU) for multislice signal acquisition Export

@article{citeulike:5911248, abstract = {Dynamic shim updating (DSU) is a technique for achieving optimal magnetic field homogeneity over extended volumes by dynamically updating an optimal shim setting for each individual slice in a multislice acquisition protocol. Here the practical implementation of DSU using all first- and second-order shims is described. In particular, the hardware modifications and software requirements are demonstrated. Furthermore, the temporal effects of dynamically switching shim currents are investigated and a Z2-to-Z0 compensation unit is described and implemented to counteract the temporal Z0 variations following a change in the Z2 shim current. The optimal shim settings for all slices are determined with a quantitative and user-independent, multislice phase-mapping sequence. The performance of DSU is evaluated from multislice phase maps and spectroscopic images acquired on rat brain in vivo. DSU improved the magnetic field homogeneity over all spatial slices, with a more pronounced effect on the slices positioned away from the magnet isocenter, thereby making the magnetic field homogeneity highly uniform over an extended volume. Magn Reson Med 49:409-416, 2003. {\copyright} 2003 Wiley-Liss, Inc.}, address = {Magnetic Resonance Center, Departments of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut}, author = {de Graaf, Robin A. and Brown, Peter B. and McIntyre, Scott and Rothman, Douglas L. and Nixon, Terence W.}, citeulike-article-id = {5911248}, citeulike-linkout-0 = {http://dx.doi.org/10.1002/mrm.10404}, citeulike-linkout-1 = {http://www3.interscience.wiley.com/cgi-bin/abstract/102531100/ABSTRACT}, doi = {10.1002/mrm.10404}, issn = {1522-2594}, journal = {Magnetic Resonance in Medicine}, keywords = {dynamic-shimming, engineering, georgios, mrm}, number = {3}, pages = {409--416}, posted-at = {2009-10-08 20:41:05}, priority = {2}, title = {Dynamic shim updating (DSU) for multislice signal acquisition}, url = {http://dx.doi.org/10.1002/mrm.10404}, volume = {49}, year = {2003} }

TY - JOUR ID - citeulike:5911248 L3 - citeulike-article-id:5911248 N2 - Dynamic shim updating (DSU) is a technique for achieving optimal magnetic field homogeneity over extended volumes by dynamically updating an optimal shim setting for each individual slice in a multislice acquisition protocol. Here the practical implementation of DSU using all first- and second-order shims is described. In particular, the hardware modifications and software requirements are demonstrated. Furthermore, the temporal effects of dynamically switching shim currents are investigated and a Z2-to-Z0 compensation unit is described and implemented to counteract the temporal Z0 variations following a change in the Z2 shim current. The optimal shim settings for all slices are determined with a quantitative and user-independent, multislice phase-mapping sequence. The performance of DSU is evaluated from multislice phase maps and spectroscopic images acquired on rat brain in vivo. DSU improved the magnetic field homogeneity over all spatial slices, with a more pronounced effect on the slices positioned away from the magnet isocenter, thereby making the magnetic field homogeneity highly uniform over an extended volume. Magn Reson Med 49:409-416, 2003. © 2003 Wiley-Liss, Inc. IS - 3 JF - Magnetic Resonance in Medicine SN - 1522-2594 AD - Magnetic Resonance Center, Departments of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut EP - 416 TI - Dynamic shim updating (DSU) for multislice signal acquisition VL - 49 SP - 409 KW - dynamic-shimming KW - engineering KW - georgios KW - mrm AU - de Graaf, Robin AU - Brown, Peter AU - McIntyre, Scott AU - Rothman, Douglas AU - Nixon, Terence PY - 2003/// UR - http://dx.doi.org/10.1002/mrm.10404 ER -