DCE-MRI定量参数预测高强度超声消融术治疗症状性子宫肌瘤首次体积消融率价值

Research on DCE-MRI Quantitative Analysis Predicts Immediate Therapeutic Response of High-Intensity Focused Ultrasound Ablation of Symptomatic Uterine Fibroids

目的探讨DCE-MRI定量渗透性与T1灌注分析预测高强度超声消融术(HIFU)治疗子宫肌瘤首次体积消融率价值。方法搜集本院29例症状性子宫肌瘤行HIFU消融治疗患者(36个肌瘤,直径3.1~9.2 cm),治疗前、后3天内分别行DCE-MRI和常规MRI检查,术前测量子宫肌瘤DCE-MRI定量参数值(K^(trans)、K_(ep)、V_e、Vp、BF、BV),术后测量肌瘤首次体积消融率,根据体积消融率划分为消融70%以上组(H组)和70%以下组(L组),回顾性分析这两组病例术前渗透性与T_1灌注定量参数值有无差别及其与体积消融率的相关性,然后采用ROC曲线评价各参数值的预测价值,寻找术前预测首次体积消融率的最佳临界值。结果 (1)H组(n=20)K^(trans)、K_(ep)、V_e、BF低于L组(n=16),差异有统计学意义(P值均<0.05),余两组各参数间无统计学差异。(2)K^(trans)、BF、BV与首次体积消融率呈负相关(r分别为-0.471、-0.452、-0.396,P值均<0.05)。(3)K^(trans)、BF、BV值预测首次体积消融率ROC曲线下面积(AUC)分别为0.803、0.809、0.750(P值均<0.05)。以体积消融率70%分界,均获得较高的敏感性和特异性。结论不同消融率组之间术前K^(trans)、K_(ep)、V_e、BF存在差异,K^(trans)、BF、BV与首次体积消融率呈负相关,即术前K^(trans)、BF、BV值越高,首次体积消融率越低,这三种参数中BF预测效能最好,K^(trans)次之。术前DCEMRI定量参数值可用于预测瘤灶的首次体积消融率,为HIFU消融治疗子宫肌瘤病例筛选和初步判断疗效提供依据。

Objective To evaluate dynamic contrastenhanced magnetic resonance imaging（ DCE-MRI） parameters in the prediction of the immediate therapeutic response of high-intensity focused ultrasound（ HIFU） therapy in the treatment of symptomatic uterine fibroids. Methods A total of 36 symptomatic uterine Fibroids（ diameter： 3. 1- 9. 2 cm） in 29 female patients were treated with MR-HIFU therapy. All patients underwent DCE-MRI and conventional MR scan in 3 days before and after HIFU treatment. The pretreatment DCE-MRI parameters（ Ktrans,Kep,Ve,Vp,BF,BV） and the post-treatment immediate non-perfused volume ratio（ NPVR） were obtained respectively. We assigned the datas to NPVR 〉 70 %and NPVR 〈 70 % group,Then analyzed the differences of DCE-MRI parameters between the previous group and the correlations between the DCE-MRI parameters and NPVR retrospectively. Receiver operating characteristic（ ROC） curve analyses were performed to determine which parameters were significant predictors for ablation efficacy and to seek for the optimal cutoff value. Results（ 1） Ktrans,Kep,Ve,BF values of the NPVR 〉 70 % group was significantly lower than the NPVR 〈70 % group（ P 〈 0. 05）,No significant correlations were found between any other parameters.（ 2） The immediate NPVR was negatively correlated with the Ktrans,BF,BV values（ r =- 0. 471,- 0. 452 and- 0. 396 respectively; P 〈 0. 05 for all）.（ 3） The area under ROC curve（ AUC） of the baseline Ktrans,BF,BV values used to predict the immediate NPVR were 0. 803,0. 809,0. 750 respectively（ P 〈 0. 05 for all）,The cutoff value of Ktrans,BF,BV provided a higher sensitivity and specificity in predicting for the ablation efficacy. Conclusion A higher Ktrans,BF,BV value deriving from pretreatment DCE-MRI suggested a poor ablation efficacy of HIFU therapy for symptomatic uterine fibroids. The BF values had the best predictive value,the Ktransvalues took second place,and the BV value was the worst. The pretreatment DCE-MRI parameters may be useful for prediction the ablation efficacy in selecting cases and evaluating the early efficacy.