Accurate flip-angle calibration for 13C MRI. Export

@article{citeulike:1784702, abstract = {(13)C imaging and spectroscopy in the presence of injected labeled compounds can vastly extend the capability of MRI to perform metabolic imaging. The details of imaging in the presence of injected compounds, however, pose new technological challenges. Pulse sequences, in general, rely on precise flip-angle (FA) calibration to create high signal-to-noise ratio (SNR), artifact-free images. Signal quantification also requires precise knowledge of the excitation FA. In MRI scans that rely on signal acquisitions from injected compounds, however, such FA calibration is challenged by low natural-abundance (13)C signal levels before injection, and by time-varying signal following injection. A method to precisely set the FA at the (13)C frequency based on FA calibration at the (23)Na frequency is presented here. A practical implementation of a coil (a dual-tuned, (23)Na/(13)C low-pass birdcage coil) suitable for this calibration in vivo is also documented. Accurate FA calibration is demonstrated at the (13)C frequency for in vivo rat experiments using this approach.}, address = {GE Global Research Center, Niskayuna, New York 12309, USA. hancu@crd.ge.com}, author = {Hancu, I. and Watkins, R. and Kohler, S. J. and Mallozzi, R. P.}, citeulike-article-id = {1784702}, citeulike-linkout-0 = {http://dx.doi.org/10.1002/mrm.21252}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/17659619}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=17659619}, doi = {10.1002/mrm.21252}, issn = {0740-3194}, journal = {Magn Reson Med}, keywords = {13c, flip\_angle, hyperpolarised}, month = {July}, number = {1}, pages = {128--133}, posted-at = {2007-10-18 15:09:47}, priority = {2}, title = {Accurate flip-angle calibration for 13C MRI.}, url = {http://dx.doi.org/10.1002/mrm.21252}, volume = {58}, year = {2007} }

TY - JOUR ID - citeulike:1784702 L3 - citeulike-article-id:1784702 N2 - (13)C imaging and spectroscopy in the presence of injected labeled compounds can vastly extend the capability of MRI to perform metabolic imaging. The details of imaging in the presence of injected compounds, however, pose new technological challenges. Pulse sequences, in general, rely on precise flip-angle (FA) calibration to create high signal-to-noise ratio (SNR), artifact-free images. Signal quantification also requires precise knowledge of the excitation FA. In MRI scans that rely on signal acquisitions from injected compounds, however, such FA calibration is challenged by low natural-abundance (13)C signal levels before injection, and by time-varying signal following injection. A method to precisely set the FA at the (13)C frequency based on FA calibration at the (23)Na frequency is presented here. A practical implementation of a coil (a dual-tuned, (23)Na/(13)C low-pass birdcage coil) suitable for this calibration in vivo is also documented. Accurate FA calibration is demonstrated at the (13)C frequency for in vivo rat experiments using this approach. IS - 1 JF - Magn Reson Med SN - 0740-3194 AD - GE Global Research Center, Niskayuna, New York 12309, USA. hancu@crd.ge.com EP - 133 TI - Accurate flip-angle calibration for 13C MRI. VL - 58 SP - 128 KW - 13c KW - flip_angle KW - hyperpolarised AU - Hancu, I AU - Watkins, R AU - Kohler, SJ AU - Mallozzi, RP PY - 2007/07// UR - http://dx.doi.org/10.1002/mrm.21252 ER -