https://scholars.lib.ntu.edu.tw/handle/123456789/341047
標題: | Accelerated proton echo planar spectroscopic imaging (PEPSI) using GRAPPA with a 32-channel phased-array coil | 作者: | Tsai, S.-Y. Otazo, R. Posse, S. Lin, Y.-R. Wald, L.L. Wiggins, G.C. Lin, F.-H. HSIAO-WEN CHUNG |
關鍵字: | 32-channel phase array; GRAPPA; MR spectroscopic imaging; Parallel MRI; PEPSI; Proton echo planar spectroscopic imaging | 公開日期: | 2008 | 卷: | 59 | 期: | 5 | 起(迄)頁: | 989-998 | 來源出版物: | Magnetic Resonance in Medicine | 摘要: | Parallel imaging has been demonstrated to reduce the encoding time of MR spectroscopic imaging (MRSI). Here we investigate up to 5-fold acceleration of 2D proton echo planar spectroscopic imaging (PEPSI) at 3T using generalized autocalibrating partial parallel acquisition (GRAPPA) with a 32-channel coil array, 1.5 cm3 voxel size, TR/TE of 15/2000 ms, and 2.1 Hz spectral resolution. Compared to an 8-channel array, the smaller RF coil elements in this 32-channel array provided a 3.1-fold and 2.8-fold increase in signal-to-noise ratio (SNR) in the peripheral region and the central region, respectively, and more spatial modulated information. Comparison of sensitivity-encoding (SENSE) and GRAPPA reconstruction using an 8-channel array showed that both methods yielded similar quantitative metabolite measures (P > 0.1). Concentration values of N-acetyl-aspartate (NAA), total creatine (tCr), choline (Cho), myo-inositol (ml), and the sum of glutamate and glutamine (Glx) for both methods were consistent with previous studies. Using the 32-channel array coil the mean Cramer-Rao lower bounds (CRLB) were less than 8% for NAA, tCr, and Cho and less than 15% for ml and Glx at 2-fold acceleration. At 4-fold acceleration the mean CRLB for NAA, tCr, and Cho was less than 11%. In conclusion, the use of a 32-channel coil array and GRAPPA reconstruction can significantly reduce the measurement time for mapping brain metabolites. © 2008 Wiley-Liss, Inc. |
URI: | http://www.scopus.com/inward/record.url?eid=2-s2.0-42549158041&partnerID=MN8TOARS http://scholars.lib.ntu.edu.tw/handle/123456789/341047 |
DOI: | 10.1002/mrm.21545 | SDG/關鍵字: | Amino acids; Brain mapping; Cramer-Rao bounds; Encoding (symbols); Magnetic resonance imaging; Metabolites; Signal encoding; Echo-planar spectroscopic imaging; GRAPPA; Mr spectroscopic imaging; Parallel MRI; PEPSI; Phase array; Signal to noise ratio; choline; creatine; glutamic acid; glutamine; inositol; n acetylaspartic acid; 32 channel phased array coil; article; brain mapping; calibration; device; diagnostic imaging; echo planar imaging; generalized autocalibrating partial parallel acquisition; human; image processing; image reconstruction; nonhuman; parallel imaging; proton echo planar spectroscopic imaging; sensitivity analysis; signal noise ratio |
顯示於: | 生醫電子與資訊學研究所 |
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