多中心扩散MRI的质量控制

Quality control of multicenter diffusion MRI

目的探讨多中心扩散MRI的质量控制方法。方法针对全国各地共8个中心相同MR机型开展多中心质量控制研究,采用相同类型水模,扫描序列和参数完全一致,分析各中心的磁场不均匀性、SNR、奈奎斯特鬼影、畸变以及FA。结果 8个中心的MR设备性能稳定性较好。所有质控参数中,奈奎斯特鬼影的波动相对较大(变异系数>15%)。同一中心各参数差异无统计学意义(P均>0.05),而不同中心各参数差异有统计学意义(P<0.001)。主成分分析表明,中心D与中心F各参数与其他中心的差异相对较大。结论同机型MR设备的多中心数据质量存在异质性。质量控制分析有助于保障扩散MRI的数据质量,为多中心大样本实验数据提供保障。

Objective To investigate the quality control method of multicenter diffusion MRI study.Methods Quality control experiments were conducted in 8 centers with the same software version.A phantom of the same design was scanned with the same pulse sequences and parameters.B0 field inhomogeneity,SNR,ghost ratio,distortion and FA were computed and compared for each scanner.Results The performance of all 8 scanners was quite stable.Among all quality parameters,field inhomogeneity was found with a slightly larger variation(coefficient of variation>15%).Inter-scanner difference existed in all measured parameters(P<0.001),whereas intra-scanner difference was not significant(all P>0.05).Parameters of center D and F differed greatly from those of other centers.Conclusion Significant heterogeneity in data quality existes among scanners of the same vendor,type and model in different centers.Quality control is necessary for multi-center diffusion MRI to improve the data quality for multi-center and large-sample studies.