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Abstract #2497

Selective TOF MRA Using Beam Saturation Pulse

Takashi Nishihara1, Hiroyuki Itagaki1, Chikako Moriwake2, David A. Lampman3, Tetsuhiko Takahashi1, Yosuke Hirata4, Kohsuke Kudo5, Makoto Sasaki5

1MRI System Division, Hitachi Medical Corporation, Kashiwa, Chiba, Japan; 2Marketing Division, Hitachi Medical Corporation, Tokyo, Japan; 3Development Center of America, Hitachi Medical Systems America, Inc., Twinsburg, OH, United States; 4Center for Radiological Sciences, Iwate Medical University Hospital, Morioka, Iwate, Japan; 5Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Iwate, Japan

We investigated use of a 2D beam excitation pulse (Beam Sat pulse) to saturate the ICA, to realize selective TOF MRA. Beam shape stability was evaluated for B0 inhomogeneity. When B0 inhomogeneity was less than 50Hz, an expansion of FWHM from specification was less than 10%. The position and direction of the Beam Sat pulse were evaluated. As the results, one side ICA was saturated selectively. Saturation effect of signal intensity in the artery was evaluated. For 7 volunteers, the signal intensity from ICA to MCA-M4 was saturated. The Beam Sat pulse is able to saturate the ICA selectively.

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