3.0TMR颈段脊髓DWI优化b值的初步研究

The Preliminary Study of the Suitable B Value in Diffusion Weighted Imaging of Cervical Spinal Cord with 3.0T MR

目的应用3.0 T磁共振采用不同扩散敏感系数(b值)对颈段脊髓行扩散加权成像(DWI)检查,优选最佳b值。方法 49例行颈段脊髓DWI检查,采用单次激发自旋回波平面成像序列,b值分别取400、600、800、1000s/mm2,测量颈段脊髓表观扩散系数(ADC)值并分析各组DWI图像及ADC图像质量,对比不同b值对成像效果的影响。结果 49例受检者均获得较满意的DWI和ADC图像。随着b值由400 s/mm2升高至1000 s/mm2,脊髓与脑脊液信噪比逐渐降低,脊髓脑脊液对比噪声比b值为600 s/mm2时最高,此后逐渐降低,且ADC参考范围较稳定。结论 b值为600 s/mm2时,颈段脊髓DWI图像质量最好,可以获得较满意的DWI及ADC图像。

Objective To determine reasonable b values in diffusion weighted imaging of cervical spinal cord with 3.0 T MR.Methods 49 normal persons received DWI of cervical spinal cord using a single shot EPI SE pulse sequence with different b values（400 s/mm2,600 s/mm2,800 s/mm2,1000 s/mm2）.ADC values of the normal cervical spinal were measured.The image quality of each group of DWI and ADC were analyzed and compared.Results The images of DWI and ADC of 49 subjects were all acquired well,and ADC values of the normal cervical spinal cord were measured.As b values increasing from 400 s/mm2 to 1000 s/mm2,SNR of spinal cord and CSF decreased gradually.When b value was 600 s/mm2,the reference range of ADC values was stable,and the SNR was the highest,and then decreased gradually.Conclusion When b values is 600 s/mm2,the image quality of DWI and ADC map of cervical spinal cord is satisfying.