目的 探究核磁共振 ( M R I ) T 2 mapping 成像对膝关节前交叉韧带重建术 后股骨髁软骨对吻损伤临床转归的评估 价值。方法 选取2013年7月至2015年6月 在我院接受前交叉韧带(ACL)重建，且在 术后3个月、半年、1年规律复查膝关节 MRI患者共计39例。成像序列包括冠状位 TSE-T2WI、矢状位TSE-T1WI、TSE-PDWI 及TSE-3D-SPC-FS。完成扫描后基于梯度 回波序列进行T2 Mapping扫描。测量项 目包括：评估股骨髁对吻损伤的ICRS(国 际软骨修复协会)分级，局部软骨厚度及 T2 Mapping下的T2值。结果 与术前相 比，术后三个月时软骨损伤分级明显降 低(χ2 =6.317，P=0.042)。而术后三个月 与半年(χ2 =4.452，P=0.108)，术后半年 与一年(χ2 =5.638，P=0.058)相比无显著 性差异。在术后不同随访期测量对吻损 伤部位软骨厚度中，术前术后在矢状面 前(F=0.067，P=0.797)、中(F=0.086， P=0.832)、后部(F=0.073，P=0.688)的比 较均无显著性差异。在T2 Mapping测量 中。对吻损伤部位的软骨T2 Mapping图像 显示关节软骨连续但不完整，局部信号 混杂不均，色阶部分呈橘红色或红色， T2值明显增高。但对损伤局部的T2值进 行术前术后比较，结果亦无统计学差异 (F=0.375，P=0.093)。结论 T2 Mapping 技术可以有效地评估前交叉韧带重建术后 软骨损伤的变化情况：在术后一年的观察 期中，术后3个月对吻损伤的骨髓水肿逐 渐消失，但软骨厚度和T2值无明显变化。

Objective To analyze radiological changes of femoral condylar cartilage kissing lesion after anterior cruciate ligament (ACL) reconstruction using magnetic resonance(MRI) T2 Mapping technique. Methods From June 2013 to July 2015, 39 cases(37 male, 2 female) who accept ACL reconstruction were included. All the patients accept MR scan before operation and at 3 months, six months, 1 year after surgery. The technique of MR scan were: Routine 2D-MRI (coronal TSE-T2WI, sagittal TSE-T1WI, sagittal TSE-PDWI sequence) and 3D-MRI (sagittal TSE-3D-SPCFS sequence) scan. Mapping T2 scan is performed based on gradient echo sequence after complete scanning.Measurement items included: assessment of the ICRS(International cartilage repaire sociaty) Grading, cartilage thickness and T2 value of the kissing lesion site femoral condyle. Results The ICRS Grading was significantly reduced (χ2=6.317, P=0.042) at three months postoperatively compaired with initial injury. However, the grading of three months and six months comparison(χ2=4.452, P=0.108),and six months to one year comparison(χ2=5.638, P=0.058) had no significant difference.In the followup time,cartilage thickness of the kissing lesion site had no significant change among all periods(front: F=0.067 P=0.797, middle: F=0.086 P=0.832, back:F=0.073 P=0.688 ).In T2 Mapping measurement: Kissing lesion revealed continuous articulation but imcomplete cartilage.In T2 mapping image the local signal mixed uneven and gradations of color is orange or red, T2 value increased significantly. However, there was no significant difference in the preoperative and postoperative values of T2 Mapping (F=0.375, P=0.093). Conclusion Mapping T2 technique can effectively evaluate the changes of cartilage injury combined with anterior cruciate ligament injury. 3 months after surgery, the edema of the bone marrow was gradually disappeared, but there was no significant change in cartilage thickness and T2 value.