【作者】 富丽萍；

【导师】 王绍武；

【作者基本信息】 大连医科大学 ， 影像医学与核医学， 2005， 硕士

【摘要】 目的:评价人体软骨的 MRI 序列,寻找其敏感序列并探讨其在关节软骨急性创伤及软骨类肿瘤病变中的应用价值。 材料与方法:前瞻性研究 2004 年 3 月至 2005 年 1 月间有明确膝关节外伤者 76 例,高度怀疑软骨类肿瘤者 7 例,行 MRI 检查。所用设备、序列、影像分析方法及统计学方法如下: (一)MR 扫描技术: 1.检查方法:应用 GE 公司 Signa 1.5TMR/i 进行检查。依据病变部位选用膝关节线圈或表面线圈,常规行矢状面、冠状面和横断面扫描。 2.MRI 序列:所有膝关节外伤病例均采用矢状面快速自旋回波T1 加权像(FSE-T1WI)、抑制脂肪的快速自旋双回波质子和 T2 加权像 ( FS-FSE-T2WI/PD )、 抑 制 脂 肪 的 三 维 快 速 扰 相 梯 度 回 波(FS-3D-T1*-FSPGR)、反相位 T1 加权三维快速扰相梯度回波(UnilateralT1-Special-3D- FSPGR)、T2*梯度回波(GR)以及横断面抑制脂肪的快速自旋回波质子密度加权像(FS-FSE-PD)。对软骨类肿瘤病变,加用快速自旋回波 T2 加权像(FSE-T2WI)和弥散加权成像(DWI),b 值取 300 s/mm3进行扫描。 (二)影像分析方法: 1.对急性膝关节创伤的 MR 各序列图像做出病变分级诊断,分析软骨及软骨下骨损伤的 MR 征象,所有 MR 诊断与关节镜检查结果相对照。 ·2·2.对软骨类肿瘤病变在 MR 各序列上的信号特点进行分析,对外生软骨瘤软骨帽的厚度作 MR 测量并与大体标本测量值相对照。(三)统计学方法:采用双盲法计算出各序列的信噪比(signal noise ratio, SNR),对比噪声比(contrast noise ratio, CNR)以及诊断软骨缺损的敏感度、特异度、准确度、阴性预测值、阳性预测值和 Kappa 值。采用 SPSS11.5 软件分别进行单因素方差分析(ANOVA)及 u 检验。CNR 的绝对值小于5 为“差,”5～10 为“一般,”10～20 为“良好,”20 以上为“极佳” 。 Kappa值≤0.4 为一致度较差,0.4~0.75 之间为一致度良好,Kappa 值≥0.75为一致度极佳。结果:76 例中 MRI 诊断软骨损伤 45 例,其中 31 人 32 例次做了关节镜检查,7 例软骨类肿瘤均用 MRI 敏感序列作出正确诊断并经病理证实。(一)MR 敏感序列:1.FS-FSE-T2WI、FS-FSE-PD、FS-3D-T1*-FSPGR 及 UnilateralT1-Special-3D-FSPGR 序列的 SNR 分别为 5.75±0.47、51.57±2.28、43.96±5.23 和 45.00±10.18。FS-FSE-T2WI 与其他三者 SNR 比较差异有显著性(P<0.05),而后三个序列之间的差异无显著性(P> 0.05)。2.将矢状面和横断面的 FS-FSE-T2WI/PD 结合分析,其诊断的敏感度为 91%、特异度为 99%、准确度为 97%、阳性预测值为 98%、阴性预 测 值 为 94% , Kappa 值 为 0.80 ; FS-3D-T1*-FSPGR 和UnilateralT1-Special-3D-FSPGR 诊断的敏感度为 81%、特异度为 97%、准确度为 95%、阳性预测值为 96%、阴性预测值为 87%, Kappa 值为0.71。两组 Kappa 值之间的差异有显著性(u=9.46,p<0.05)。(二)软骨损伤的MR征象:1.急性软骨损伤的 MR 征象:(1)软骨局限性轻度增厚,其内信号异常;(2)压缩性骨软骨骨折,表现为软骨及软骨下低信号线的局限性内陷,软骨下斑片状 T1WI 低信号 T2WI 高信号影;(3)软骨表面部分缺失,凸凹不平或软骨全层缺失,边缘锐利,伴有软骨下低信号线模糊;(4)软骨连续性中断,游离端呈瓣样掀起,软骨与软骨下骨之间被线样更多还原

【Abstract】 PURPOSE: To evaluate MR sequences of human cartilage and search for the most valuable sequence and explore its clinical application in the acute chondral trauma and cartilaginous tumors. MATERIAL AND METHODS: 31 patients with acute injury history and the results of arthroscopies and 7 patients with cartilaginous tumors were studied in MRI. The methods are as follows: 1. All MR images were performed from GE Signa 1.5 TMR/i scanner. The sequences included: Sagittal T1 weighted fast spin-echo (FSE-T1WI), T2 weighted fast spin-echo (FSE-T2WI),dual-echo fast spin-echo with fat-suppressed(FS-FSE-T2WI/PD),fat-saturation three-dimensional fast spoiled gradient echo ( FS-3D-T1*-FSPGR ) ,out phase T1 weighed three-dimensional fast spoiled gradient echo(UnilateralT1-Special-3D- FSPGR),T2 weighted gradient echo(GR),diffusion weighted imaging(DWI, b=300s/mm3)and Axial fat- suppressed fast spin-echo proton density(FS-FSE-PD)。 2. Given the staging diagnosis of chondral lesions , analyzed the MR appearance of injuried cartilage and subcartilaginous bone and the signal characters of cartilaginous tumors, measured the width of cartilage cap. All MR diagnosis compared with the results of arthroscopies and gross specimens. 3. The statistic methods: using SPSS 11.5 software. RESULTS: 1. The SNR of FS-FSE-T2WI,FS-FSE-PD, FS-3D-T1*-FSPGR, UnilateralT1-Special-3D- FSPGR were 5.75±0.47,51.57±2.28,43.96±5.23 and 45.00 ± 10.18. There was statistic significance between FS-FSE-T2WI and other 3 sequences. Among the latter 3 sequences, there were no statistic significance. 2. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and Kappa value of combined Sagittal and Axial FS-FSE-T2WI/PD were 91%, 99%, 97%, 98%, 94%, 0.80,respectively; 81%, 97%, 95%, 96% ,87% ,0.71 with FS-3D-T1*-FSPGR and UnilateralT1-Special-3D- FSPGR. There was significance of Kappa value between the FS-FSE-T2WI/PD and FS-3D-T1*-FSPGR. 3. The MR appearance of chondral lesions included:① cartilage thicken with abnormal signal;② osteochondral compression fracture;③ partial or full-thick defection of cartilage with or without subcartilaginous bone abnormal signal;④ abruption of chondral surface, flap-like free segment and fluid-like signal at the cartilage-bone junction; ⑤ osteochondral delamination ,broken, in situ or out of place. 4. 6 of 7 cartilaginous tumors had similar signal characters: low signal on T1WI, slightly bright signal on T2WI, brilliant high signal on FS-FSE-T2WI/PD and GR, slightly high signal on FS-3D-T1*-FSPGR and UnilateralT1-Special-3D-FSPGR, homogeneous high signal on DWI. The measurements of cartilage cap in GR sequence were closest to the gross specimens. CONCLUSION: 1. FS-FSE-T2WI/PD is the most sensitive sequence of articular cartilage lesions. 2. UnilateralT1-Special-3D-FSPGR sequence has the same diagnostic capability with FS-3D-T1*-FSPGR, higher SNR and fewer acquisition timethan FS-3D-T1*-FSPGR sequence. So UnilateralT1-Special-3D- FSPGR can take the place of FS-3D-T1*-FSPGR used in clinic completely. 3. MR can reflect the random and degree of acute cartilage trauma accurately and help clinic therapy choosing and following observation. 4. Cartilaginous tumors had specific MR appearance. Among the cartilage sensitive sequences of FS-FSE-T2WI/PD, FS-3D-T1*-FSPGR , UnilateralT1-Special-3D-FSPGR and Heavy T2 weighted GR ,the Heavy T2 weighted GR sequence is the most valuable MR sequence of diagnosis in cartilaginous tumors.更多还原