MR弥散加权成像诊断股骨头坏死

目的探讨MR DWI在股骨头坏死诊断及分期中的价值。方法应用MR SE-EPI-DWI序列对34例股骨头坏死患者共40个髋关节根据Steinberg分期分为I～Ⅱ期(第1组)、Ⅲ～Ⅳ期(第2组)、Ⅴ～Ⅵ期(第3组)]及90名健康志愿者共180个髋关节进行图像采集,b值分别选取300、500、700s/mm2。应用Functool软件进行分析,得到ADC图。选取ROI为100mm2,测量双侧股骨头的ADC值,并进行统计学分析。结果 b值为300、500、700s/mm2时,股骨头坏死患者股骨头的ADC均值分别为(13.00±2.54)×10-4 mm2/s、(10.73±3.10)×10-4 mm2/s、(8.77±1.55)×10-4 mm2/s,正常股骨头的ADC均值分别为(3.63±1.34)×10-4 mm2/s、(1.87±0.76)×10-4 mm2/s、(1.49±0.53)×10-4 mm2/s,差异均有统计学意义(P均<0.05)。第1组股骨头坏死区ADC值最小,第2组ADC值最大,而第3组ADC值又减小,差异有统计学意义(P<0.05)。结论 MR DWI可以清晰显示股骨头坏死的病变区域,ADC值对于区分正常及病变区域、指导股骨头坏死分期有一定价值。

MR diffusion imaging in diagnosis of femoral head necrosis

Objective To assess the value of MR DWI in diagnosis and staging of femoral head necrosis.Methods Thirty-four patients with femoral head necrosis(40 hip joints) and 90 healthy volunteers(180 hip joints) were included.The patients were divided into 3 groups according to Steinberg stage(Ⅰ—Ⅱ of group 1,Ⅲ—Ⅳ of group 2,Ⅴ—Ⅵ of group 3).SE-EPI-DWI was performed to obtain images with b values of 300,500 and 700 s/mm2,respectively.ADC maps were obtained with Functool software.ADC values of femoral head were measured using 100 mm2 ROIs,and then were statistically analyzed.Results With b value of 300,500 and 700 s/mm2,the mean ADC value of femoral head necrosis was(13.00±2.54)×10-4 mm2/s,(10.73±3.10)×10-4 mm2/s and(8.77±1.55)×10-4 mm2/s,respectively,while the mean ADC value of healthy femoral heads was(3.63±1.34)×10-4 mm2/s,(1.87±0.76)×10-4 mm2/s,(1.49±0.53)×10-4 mm2/s.There were significant statistical differences in ADC values of normal femoral head and femoral head necrosis(all P<0.05).ADC values of femoral head necrosis in group 1 were minimum,and were maximum in group 2,then reduced in group 3(P<0.05).Conclusion DWI can display the femoral head necrosis clearly.ADC values contribute to distinguishing the normal and pathological regions of femoral head,as well as staging necrosis of the femoral head.