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Abstract #0219

Novel Automatic Off-Resonance Correction Without Field Maps in Spiral Imaging Using L1 Minimization

Hisamoto Moriguchi1, Kohki Yoshikawa2, Morio Shimada2, Shin-ichi Urayama3, Yutaka Imai1, Manabu Honda4, Takashi Hanakawa4

1Radiology, Tokai University, Isehara, Kanagawa, Japan; 2Radiological Sciences, Komazawa University, Tokyo, Japan; 3Human Brain Research Center, Kyoto University, Kyoto, Japan; 4Functional Brain Research, National Center of Neurology and Psychiatry, Tokyo, Japan

A primary disadvantage of spiral imaging is blurring artifacts due to off-resonance effects. Most spiral off-resonance correction methods require a frequency field map. However, to acquire a field map increases the scan time. In this study, a novel spiral automatic off-resonance correction method without field maps has been demonstrated. In the newly proposed method, L1 minimization is used as a new criterion to determine the correct off-resonance frequencies. Frequency estimation process of the L1 min off-resonance correction is robust and the estimated field map shows reduced errors. The L1 min off-resonance correction has significant potential for faster spiral acquisition.

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Keywords

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