动态增强MRI定量灌注直方图参数对富细胞型子宫肌瘤的诊断价值

Quantitative perfusion histogram parameters of dynamic contrast-enhanced MRI to identify cellular leiomyoma

目的探讨动态对比增强MRI（DCE-MRI）定量灌注直方图参数鉴别富细胞型子宫肌瘤的价值。方法回顾性分析2015年10月至2017年9月在绍兴市人民医院就诊且手术病理证实为子宫肌瘤的71例患者，术前行盆腔DCE-MRI检查并测量各定量灌注参数[包括容量转运常数（Ktrans）、速率常数（Kep）、血管外细胞外间隙容积分数（Ve）、血管间隙容积分数（Vp）]的直方图参数（中位数、平均值、偏度、峰度、能量、熵）。子宫肌瘤按病理分为退变型、普通型、富细胞型。3种病理类型组间资料采用单因素ANOVA方法（方差齐）或多个独立样本Kruskal-Walls检验（方差不齐）比较，两两比较采用LSD法（方差齐）或Mann-Whitney检验（方差不齐）法。筛选有统计学意义的参数绘制ROC曲线，评价各参数的诊断效能。结果3种不同病理类型子宫肌瘤的Ktrans（中位数、平均值、峰度、能量、熵），Kep（中位数、平均值、偏度、峰度、熵），Ve（中位数、平均值、偏度、峰度），Vp（中位数、平均值、偏度、峰度、能量、熵）差异均有统计学意义（P均〈0.05）。其中，富细胞组Ktrans、Kep、Vp的（中位数、平均值）与Ktrans（熵）高于退变组和普通组，Ktrans（峰度、能量）、Kep（偏度）低于退变组和普通组；Kep（峰度）低于普通组、而Kep（熵）高于普通组；Ve（中位数、平均值、峰度）、Vp（熵）高于退变组，Ve（偏度）、Vp（偏度、峰度、能量）低于退变组。当Ktrans中位数为0.994/min时，其敏感度为100.0%，特异度73.8%，ROC下面积为0.905；当Ktrans平均值为1.170/min时，其敏感度为90.0%，特异度为85.2%，ROC下面积为0.921；Ktrans（峰度、能量、熵）、Kep（中位数、平均值、偏度、峰度、熵）、Ve（中位数、平均值、偏度）、Vp（中位数、平均值、偏度）ROC下面积较高（0.711～0.872）。结论DCE-MRI定量灌注直方图参数鉴别富细胞型子宫肌瘤具有较高价值。

ObjectiveTo evaluate the value of histogram parameters of dynamic contrast-enhanced MRI （DCE-MRI） in the diagnosis of cellular leiomyoma. MethodsSeventy one patients with leiomyomas confirmed by pathology who underwent preoperative DCE-MRI were enrolled in this retrospective study. Quantitative perfusion histogram parameters （including median, mean, skewness, kurtosis, energy, entropy） were measured for each patient. Leiomyoma was divided into degeneration, ordinary and cellular types according to pathology. One-way analysis of variance and Least significant difference were used to compare the differences among the parameters of the three groups which were normal distribution and equal variances, while Kruskal-Walls test and Mann-Whitney U test were used to compare the parameters that did not conform to normal distribution or variance. ROC curves were drawn to evaluate the diagnostic efficiency of different parameters. ResultsAmong the three groups, the values of Ktrans （median, mean, kurtosis, energy, entropy） , Kep （median, mean, skewness, kurtosis, entropy）, Ve （median, mean, skewness, kurtosis） and Vp （median, mean, skewness, kurtosis, energy, entropy） had statistical difference （all P〈0.05）. The values of Ktrans, Kep, Vp （median, mean） and Ktrans （entropy） of the cellular group were higher than those of the degeneration and ordinary groups. While the values of Ktrans （kurtosis, energy） and Kep （skewness） of the cellular group were lower than the other two groups; then the value of Kep （kurtosis） of the cellular group was lower than the ordinary group and the value of Kep （entropy） of the cellular group was higher than the ordinary group; and the values of Ve （median, mean, kurtosis） and Vp （entropy） of the cellular group were higher than those of the ordinary group. The values of Ve （skewness） and Vp （skewness, kurtosis and energy） of the cellular group were lower than those of degeneration group. ROC curves found that when Ktrans （median） was 0.994/min, its sensitivity was 100.0%, the specificity was 73.8%, and the area under ROC was 0.905; when Ktrans （mean） was 1.170/min, its sensitivity was 90.0%, the specificity was 85.2%, the area under ROC was 0.921. And the areas under ROC of Ktrans （kurtosis, energy, entropy）, Kep （median, mean, skewness, kurtosis, entropy）, Ve （median, mean, skewness）, Vp （median, mean, skewness） were also high （ranging from 0.711 to 0.872）.ConclusionHistogram analysis of DCE-MRI quantitative perfusion is applicable for identification of cellular leiomyoma.