3D-WATS序列与T_2 mapping测量正常成年男性膝关节软骨厚度的研究

The Value of 3DWATS and T_2 mapping on the Measurement of Normal Adult Male Knee Joint Cartilage Thickness

目的探讨1．5TMRI三维扰相脂肪抑制梯度回波（3D—WATS）序列与T2弛豫时间图（T2mapping）原始图像序列测量正常成年人膝关节关节软骨厚度差异性，评价T2mapping原始图像的临床应用价值。方法选取95名正常20～35岁成年男性膝关节，行矢状位扫描，用3D—WATS和T2mapping原始图像，分别选取胫骨内外侧髁连线外1／4图像作为测量层面，每个膝关节测量平面选取3个测量点，测量结果用同源配对样本均数t检验比较测量值。结果正常成年男性膝关节软骨胫骨内外侧髁连线外侧1／4前后相同层面，相同测量点上3DWATS与T：mapping原始序列测量结果之间差异无统计学意义（t1=0．025，t2=1．868，P值均〉0．05）。在同层面胫骨软骨中点相同的测量点之间差异具有统计学意义（t=9．20，P〈0．05），3D—WATS较T2mapping序列测量软骨厚度大。结论正常成年人膝关节软骨厚度测量T2mapping原始图像可代替3D—WATS序列，且T2mapping序列原始灰阶图还可观察关节积液及半月板形态，T2mapping虽然测量胫骨软骨厚度不如3D—WATS序列，但仍可以观察软骨的连续是否完整。

Objective To explore the difference of observed value about normal adult knee articular cartilage thickness measured by 3D WATS and T2 mapping original image with 1.5T MR. Methods 95 normal adult male（age ranged from 20 to 35 years） knee underwent sagittal 3D WATS and T2 mapping sequence. We selected measurement level as a quarter of the lateral about the distance between tibial medial condyle and lateral condyle. 3 points was selected in each knee meas urement plane. Homologous pairs sample mean t test was used to compare the measurements. Results In the same level and same measurement point of normal adult male knee joint cartilage, there was no statistical significant difference between the measurements in a quarter of the lateral about the distance between tibial medial condyle and lateral condyle in 3DWATS and T2 mappingoriginalimage （ t1 = 0. 025 ,t2 = 1. 868 ,P 〉 0.05 ）. There was statistical significant difference be tween 3DWATS and T2 mapping original image in the same survey points with the middle level of tibial cartilage（ t = 9. 20, P 〈 0.05 ）. The measurement of the cartilage thickness in 3D WATS was more thick than that in T2 mapping. Conclusion T2 mapping original image can replace the 3DWATS sequence in measurement of normal adult knee joint cartilage thick ness. In addition, the joint effusion and meniscus shape is observed in T2 mapping original image. 3DWATS is superior to T2 mapping for measurement of tibial cartilage thickness,however, the integrity of the cartilage can be observed in T2 map ping.