DCE-MRI定量分析对垂体腺瘤诊断价值的分析

Diagnose pituitary adenoma using dynamic enhanced MRI： a quantitative approach

目的 探讨动态增强磁共振成像（DCE-MRI）定量分析对垂体腺瘤的诊断价值.方法 收集皖南医学院第一附属医院2013年6月至2014年12月以病理及随访等结果作为金标准判定67例微腺瘤、20例大腺瘤和15例正常垂体,对其行常规扫描和动态增强扫描,观察病灶图像特征并测量正常垂体、微腺瘤以及大腺瘤的定量参数：容量转移常数（Ktrans）、速率常数（Kep）、血管外细胞外间隙容积比（Ve）数值大小.对微腺瘤、大腺瘤和正常垂体间及微腺瘤中的泌乳素瘤和生长激素瘤间各定量参数值进行比较,并绘制ROC曲线.结果 67例微腺瘤通过常规检查可诊断61例,诊断准确率为91.1％.正常垂体的Ktrans、Kep、Ve均值分别为（0.90±0.23）/min,（1.14±0.58）/min,1.02±0.51;垂体微腺瘤分别为（0.46±0.23）/min,（0.80 ±0.27）/min,0.73 ±0.32;垂体大腺瘤分别为（0.41 ±0.25）/min,（0.71 ±0.48）/min,0.66±0.40.正常垂体Ktrans值分别高于微腺瘤和大腺瘤,差异均有统计学意义（均P ＜0.05）;正常垂体Kep值也分别高于微腺瘤和大腺瘤,差异均有统计学意义（均P＜0.05）;三组间Ve值差异无统计学意义.泌乳素瘤Ktrans值高于生长激素瘤,差异有统计学意义（P＜0.05）,两者间Kep和Ve差异无统计学意义.在检出微腺瘤时Ktrans、Kep的ROC曲线下面积分别为0.915、0.738,二者诊断垂体微腺瘤的敏感性分别为92.3％、53.8％,特异性分别为85％、100％.结论 DCE-MRI定量参数Ktrans、Kep有助于垂体腺瘤的检出,且Ktrans诊断效能更高,Ktrans的诊断价值高于MRI常规方法;同时Ktrans对不同分泌类型的垂体微腺瘤有一定的鉴别诊断价值.

Objective To evaluate the diagnostic value of quantitative Dynamic Contrast Enhanced MRI analysis on pituitary adenoma.Methods With the standard of pathology and follow-up results,67 cases of microadenoma,20 cases of macroadenoma and 15 cases of normal pituitary were selected and taken routine scanning,meanwhile the dynamic contrast-enhanced scanning was performed,then the characteristics of lesions on conventional images were analyzed,and the mean permeability parameters were measured,including transfer rate （Ktrans）,back flux rate （Kep）,fractional EES volume （Ve） using Tofts model,which were compared with each other among those three groups and between prolactinoma and somatotroph adenoma;finally,the areas under the ROC curve of permeability parameters were compared.Results 61 cases of 67 cases of pituitary adenoma could be diagnosed by conventional methods,therefore the diagnostic accuracy was 91.1%.The Ktrans,Kep and Ve values were（0.90 ±0.23）/min,（1.14 ±0.58）/min,1.02 ± 0.51 respectively in normal pituitary,and （0.46 ± 0.23）/min,（0.80 ± 0.27）/min,0.73 ± 0.32 in microadenoma and （0.41 ±0.25）/min,（0.71 ±0.48）/min,0.66 ±0.40 in macroadenoma.The Ktrans and Kep in normal adenoma were respectively higher than in microadenoma and macroadenoma,and the difference had statistical significance （P 〈 0.05）,while the Ve value among these three groups had no statistical significance;the Ktrans in prolactinoma was higher than in somatotroph adenoma,and the difference had statistical significance （P 〈 0.05）,while the difference of Kep and Ve between prolactinoma and somatotroph adenoma had no statistical significance.The area under the ROC curve in finding the microadenoma,Ktrans,Kep were 0.915 and 0.738,and the sensitivity of Ktrans and Kep were 92.3% and 53.8%,and the specificity of Ktrans and Kep were 85% and 100%.Conclusion Dynamic contrast-enhanced quantitative parameters,Ktrans and Kep are help to the diagnosis of pituitary adenoma,and K exhibits a relatively high diagnostic efficacy,and the value of diagnosis in Kt is higher than which in MRI conventional method;while Ktrans can differentiate certain secreting type of pituitary microadenoma.