对软骨的定量MRI T1和T2弛豫时间进行聚类分析，可识别出3T条件下健康个体与前交叉韧带损伤个体之间的差异。

Cluster analysis of quantitative MRI T and T relaxation times of cartilage identifies differences between healthy and ACL-injured individuals at 3T.

作者信息

Monu U D, Jordan C D, Samuelson B L, Hargreaves B A, Gold G E, McWalter E J

机构信息

Department of Radiology, Stanford University, Stanford, CA, USA; Department of Electrical Engineering, Stanford University, Stanford, CA, USA.

Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA.

出版信息

Osteoarthritis Cartilage. 2017 Apr;25(4):513-520. doi: 10.1016/j.joca.2016.09.015. Epub 2016 Oct 5.

DOI:10.1016/j.joca.2016.09.015

PMID:27720806

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5359021/

Abstract

PURPOSE

To identify focal lesions of elevated MRI T and T relaxation times in articular cartilage of an ACL-injured group using a novel cluster analysis technique.

MATERIALS AND METHODS

Eighteen ACL-injured patients underwent 3T MRI T and T relaxometry at baseline, 6 months and 1 year and six healthy volunteers at baseline, 1 day and 1 year. Clusters of contiguous pixels above or below T and T intensity and area thresholds were identified on a projection map of the 3D femoral cartilage surface. The total area of femoral cartilage plate covered by clusters (%CA) was split into areas above (%CA+) and below (%CA-) the thresholds and the differences in %CA(+ or -) over time in the ACL-injured group were determined using the Wilcoxon signed rank test.

RESULTS

%CA+ was greater in the ACL-injured patients than the healthy volunteers at 6 months and 1 year with average %CA+ of 5.2 ± 4.0% (p = 0.0054) and 6.6 ± 3.7% (p = 0.0041) for T and 6.2 ± 7.1% (p = 0.063) and 8.2 ± 6.9% (p = 0.042) for T, respectively. %CA- at 6 months and 1 year was 3.0 ± 1.8% (p > 0.1) and 5.9 ± 5.0% (p > 0.1) for T and 4.4 ± 4.9% (p > 0.1) and 4.5 ± 4.6% (p > 0.1) for T, respectively.

CONCLUSION

With the proposed cluster analysis technique, we have quantified cartilage lesion coverage and demonstrated that the ACL-injured group had greater areas of elevated T and T relaxation times as compared to healthy volunteers.

摘要

目的

使用一种新型聚类分析技术，识别前交叉韧带损伤组关节软骨中磁共振成像（MRI）T1和T2弛豫时间升高的局灶性病变。

材料与方法

18例前交叉韧带损伤患者在基线、6个月和1年时接受了3T MRI T1和T2弛豫测量，6名健康志愿者在基线、1天和1年时接受了测量。在三维股骨软骨表面的投影图上，识别出高于或低于T1和T2强度及面积阈值的连续像素簇。将股骨软骨板被簇覆盖的总面积（%CA）分为高于（%CA+）和低于（%CA-）阈值的区域，并使用Wilcoxon符号秩检验确定前交叉韧带损伤组中%CA（+或-）随时间的差异。

结果

前交叉韧带损伤患者在6个月和1年时的%CA+高于健康志愿者，T1的平均%CA+分别为5.2±4.0%（p = 0.0054）和6.6±3.7%（p = 0.0041），T2的平均%CA+分别为6.2±7.1%（p = 0.063）和8.2±6.9%（p = 0.042）。T1在6个月和1年时的%CA-分别为3.0±1.8%（p>0.1）和5.9±5.0%（p>0.1），T2在6个月和1年时的%CA-分别为4.4±4.9%（p>0.1）和4.5±4.6%（p>0.1）。