合成磁共振成像评估前交叉韧带早期退变的价值

The value of synthetic MRI in assessing early degeneration injury of anterior cruciate ligament

目的:探讨合成磁共振成像(SyMRI)评估前交叉韧带(ACL)早期退变的临床价值。方法:搜集80例患者的单侧膝关节合成磁共振成像数据。根据关节镜结果将所有患者分为3组:正常组(30例)、早期轻微退变组(28例)和早期明显退变组(22例)。采用单因素方差分析比较各组患者ACL的T_(1)值、T_(2)值及质子密度(PD)值的总体差异性,并采用LSD-t检验对各参数进行组间两两比较。采用受试者工作特征(ROC)曲线评估各项参数值对ACL早期退变的诊断效能。结果:单因素方差分析结果显示,T_(1)值、T_(2)值和PD值在3组间总体分布的差异均具有统计学意义(F=11.248、11.991和118.162,P均<0.001)。LSD-t检验结果显示,正常组的PD值低于轻微退变组,轻微退变组的PD值低于明显退变组,差异均具有统计学意义(P均<0.05)。T_(1)值及T_(2)值在正常组与轻微退变组之间的差异无统计学意义(P均>0.05),而正常组和轻微退变组的T_(1)值及T_(2)值均低于明显退变组(P均<0.05)。ROC曲线分析结果显示T_(1)值对ACL早期退变的敏感度、特异度、约登指数及曲线下面积分别为58%、80%、0.38和0.706,T_(2)值的相应指标值分别为88%、40%、0.28和0.677,PD值的相应指标值为92%、90%、0.82和0.957。结论:合成磁共振成像质子密度值可定量评估前交叉韧带早期退变性损伤。

Objective:To investigate the clinical value of synthetic magnetic resonance imaging(SyMRI)in assessing early degeneration injury of anterior cruciate ligament(ACL).Methods:80 unilateral knees of patients underwent SyMRI scan were collected and divided into normal group(30 cases),early mild degeneration group(28 cases)and early manifest degeneration group(22 cases)based on the results of arthroscopy.The population distribution of T_(1),T_(2) and proton density(PD)values among three groups were compared by One-way ANOVA,and LSD-t test was used to compare these parameters between each two groups.Mild and manifest degeneration were defined as early degeneration,and the diagnostic efficacy of each parameter for ACL early degeneration were assessed by recei-ver operating characteristic(ROC)curve.Results:The results of One-way ANOVA analysis showed that the population distribution of T_(1),T_(2)and PD values among the three groups were all statistically different(F=11.248,11.991 and 118.162;all P<0.001).LSD-t test showed that the PD values in normal group were lower than that in mild degeneration group,while the PD values in mild degeneration group were lower than that in manifest degeneration group(all P<0.05).There were no significant difference in T_(1)and T_(2) values between normal group and mild degeneration group(all P>0.05),while the T_(1)and T_(2) values in normal group and mild degeneration group were lower than those in manifest degeneration group(all P<0.05).The results of the ROC analysis revealed that the sensiti-vity,specificity,Youden index and area under the ROC curve of T_(1)-value were 58%,80%,0.38 and 0.706,those of T_(2)-value were 88%,40%,0.28,and 0.677,respectively;and those of PD value were 92%,90%,0.82 and 0.957,respectively.Conclusion:The PD values in SyMRI can quantitatively evaluate the early degeneration injury of ACL.