并行采集技术与相控阵线圈的品质对图像质量的影响

目的:探讨并验证并行采集技术与相控阵线圈品质对于图像质量的影响.方法:实验分两步进行,以标准水模(2%的硫酸铜溶液)作为实验对象,分别用通道正常和通道部分损坏的头颈联合线圈进行对比扫描.先采用Axial FSET1 WI序列扫描,将所得图像用GE的NEMA软件计算各个通道信噪比,并记录结果以评定不同通道与信噪比的关系;然后用ASSET序列采集Sagittal FSE T1 WI,依次取加速因子为1、1.25、1.5、1.75和2,所得数据同样使用NEMA软件计算图像信噪比,并与前部分数据结合,描点于平面直角坐标系上,以检测加速因子与信噪比的关系.结果:在常规FSE序列中,相控阵线圈能够很好的消除单个接收通道性能下降所造成的影响;在并行采集中,随着加速因子的增大,接收通道的损坏会造成重建图像质量的显著性下降.结论:并行采集技术能有效的提高成像速度,最大程度的发挥多通道相控阵线圈的能力,但当线圈通道部分损坏时,将直接导致图像质量的下降.

Impact of Phase Array Performance and Parallel Acquisition on Imaging Quality

Objective:To explore the effect of coil element performance using parallel acquisition on imaging quality.Methods:A good and a partially damaged neurovascular phase array were chosen to scan the same phantom of 2% CuSO4 solution respectively.There were two groups for scanning,the first group was scanned on axial plane with T1 weighted using fast spin echo protocol,the second group was scanned on sagitta plane with the same parameters but using a different array spatial sensitivity encoding technique(ASSET) accelerated factors of 1,1.25,1.5,1.75 and 2 each time.All the above results were calculated by NEMA software and combined into diagram to investigate the relationship between accelerated factor and SNR.Results:In routine spin echo scanning,the phase array could reduce the bad effects caused by injured recei-ving coil element.But in parallel acquisition,the damaged receiving coil would decrease the image quality obviously.Conclusion:The parallel acquisition can reduce the scanning time effectively and make full use of the potential of phase array,but the receiving coil element performance decay can result in a decrease of the image quality immediately.