摘要
目的：通过比较健康志愿者骶髂关节MRI在不同b值时弥散加权成像（ DWI）表现及表观扩散系数（ADC）值的差异，探寻3.0T MRI弥散加权成像显示骶髂关节的最适宜b值。方法选择23名健康志愿者，年龄18～37岁，采用3.0 T超导磁共振扫描仪，行骶髂关节斜冠状T1 WI、抑脂T2WI及多b值（0、400、600、800 s／mm2）DWI扫描，观察不同b值时双侧骶髂关节的显示情况；测量双侧骶髂关节的骶侧、髂侧关节旁骨髓不同b值时的ADC值并进行统计学分析。结果 b值为400、600 s／mm2时，DWI图像清晰，无变形，无明显伪影产生，对比度良好；b值为800 s／mm2时，图像伪影稍大，并可见轻度变形，对比度略差。双侧骶髂关节旁骨髓ADC值随b值增加逐渐变小；方差分析显示，4个部位的3组骨髓ADC值间差异均有统计学意义。 b值为600 s／mm2时，双侧髂骨及骶骨骨髓ADC值间差异无统计学意义；b值为600 s／mm2和800s ／mm2时，双侧骶髂关节旁骨髓ADC值离散度小；b值为400 s／mm2时，ADC值离散度大。结论 b值为600 s／mm2时，骶髂关节的ADC值稳定可靠、图像质量好，为DWI扫描的适宜b值。
Objective To compare diffusion weighted imaging （ DWI） results in different b values and apparent diffusion coefficient （ ADC） values of sacroiliac joint in healthy volunteers , for searching the optimal b value of sacroiliac joint displayed by 3.0T MRI DWI.Methods Twenty-three healthy volunteers were enrolled randomly in this study .Oblique coronal plane T1WI and fat suppression T2WI as well as multi-b value（0,400,600,800 s/mm2）DWI were performed by 3.0T superconducting MRI scanner.The displayed results were observed on bilateral sacroiliac joint and ADC values of bone marrow besides the sacroiliac joint were measured with different b values .Statistical analysis was performed .Results Clear images with high contrast ratio of 23 healthy volunteers could clearly show the sacroiliac joints when the b values were 400 s/mm2 and 600 s/mm2 .When the b value was 800 s/mm2 , the images had larger image artifacts , fuzzy image quality and poor contrast ration .The ADC values of bone marrow besides bilateral sacroiliac joint decreased gradually with the increase of the b values .The differences on ADC values of bone marrow of right ilium ,right sacrum and besides left sacroiliac joint were statistically significant .When the b value was 600 s/mm2 ,there was no statistical significance on the ADC value of bone marrow of bilateral ilium and sacrum .When the b value was 600 s/mm2 and 800 s/mm2 ,the dispersion of ADC of sacroiliac joint surrounding bone marrow was small , while the b value was 400 s/mm2 ,the dispersion of ADC of sacroiliac joint was large .Conclusion When the b value is 600 s/mm2 ,the ADC value of the sacroiliac joint is stable and reliable ,has good image quality .The optimal b value for sacroiliac joint DWI scanning is 600 s/mm2 .
出处
《中华消化病与影像杂志（电子版）》
2015年第5期4-7,共4页
Chinese Journal of Digestion and Medical Imageology(Electronic Edition)
关键词
脊柱炎
强直性
骶髂关节
磁共振成像
弥散加权成像
表观扩散系数
Spondylitis, ankylosing
Sacroiliac joint
Magnetic resonance imaging
Diffusionweighted imaging
Apparent diffusion coefficient
