ADC值及ADC比值在Ia期子宫内膜癌与子宫黏膜下肌瘤鉴别诊断中的应用价值

Value of ADC and ADC ratio in differential diagnosis of stage Ia endometrial carcinomas and submucous myomas

目的探讨MRI弥散加权成像(DWI)的表观扩散系数(ADC)、ADC比值(rADC)及ADC值的离散系数(CV)在Ia期子宫内膜癌与子宫黏膜下肌瘤鉴别诊断中的应用价值。方法选取西南医科大学附属医院68例行MRI平扫、动态增强扫描及DWI成像的Ia期子宫内膜癌与子宫黏膜下肌瘤患者,分别对病灶及正常子宫肌层、臀大肌、闭孔内肌进行ADC值的测定(b=800 s/mm2),并计算相应的rADC值。再计算CVADC值。比较Ia期子宫内膜癌与子宫黏膜下肌瘤的ADC值、rADC值及CVADC值,采用独立样本t检验和受试者操作特征(ROC)曲线评估其诊断效能。结果 Ia期子宫内膜癌组ADC值、rADC值低于子宫黏膜下肌瘤组(P <0.05),而CVADC值高于子宫黏膜下肌瘤组(P <0.05)。单项指标ROC曲线分析结果显示,ADC值曲线下面积为0.933,rADC值曲线下面积为0.878、0.882和0.913,均大于CV值曲线下面积0.665,联合指标ROC曲线分析结果显示,各联合指标曲线下面积均大于各单项指标。结论 ADC值和rADC值在鉴别Ia期子宫内膜癌与子宫黏膜下肌瘤中具有较高的诊断价值,但rADC值的诊断效能并未优于ADC值,CVADC值在鉴别Ia期子宫内膜癌与子宫黏膜下肌瘤中诊断效能较低,ADC值联合rADC臀大肌值对鉴别这2种疾病具有更高的价值。

Objective To evaluate the value of apparent diffusion coefficient(ADC),ratio of ADC(rADC)and coefficient variance(CV)of ADC value in differential diagnosis of stage Ia endometrial carcinomas and submucous myomas.Methods Sixty eight patients with stage Ia endometrial carcinoma and submucous myoma underwent MRI plain scan,dynamic contrast-enhanced scan and DWI.The ADC values of lesions and normal uterine myometrium,gluteus maximus and musculi obturator internus were measured respectively,and the corresponding rADC value and CVADC were calculated.The ADC value,rADC value and CVADC value of stage Ia endometrial carcinomas and submucosal myomas were compared.The efficiencies of ADC value and rADC value and CVADC value were assessed by independent sample t test and receiver operating characteristic(ROC)curve.Results The ADC value and rADC value in stage Ia endometrial carcinomas group were significantly lower than those in submucous myoms group(P<0.05),while the CVADC value was higher than that in submucous myomas group(P<0.05).The results of single index ROC curve analysis showed that the area under ADC value curve (0.933) and rADC value curve (0.878, 0.882, 0.913)were significantly larger than that under CVADC value curve (0.665). The results of combined index ROC curveanalysis showed that the area under each combined index curve was larger than that under each single index.Conclusions ADC value and rADC value have high diagnostic value in differentiating stage Ia endometrialcancer from submucosal myoma, but the diagnostic efficiency of rADC value is not better than that of ADCvalue. CVADC value is less effective on differentiating stage Ia endometrial cancer from submucosal myoma. ADCvalue combined with rADC gluteal muscle value have higher value in identifying these two diseases.