3.0T MR扩散加权成像在宫颈癌诊断中的应用价值

目的探讨正常宫颈、宫颈癌DWI的表现特征和表观扩散系数(ADC)值,评估DWI在宫颈癌诊断中的应用价值。方法对44例宫颈癌患者术前行常规MRI、增强及扩散加权成像,测量宫颈癌癌灶ADC值,并以20例成年健康女性志愿者宫颈扩散加权成像做为对照组,测量正常宫颈三层结构的弥散信号强度,分别计算ADC值,并与宫颈癌组进行比较;绘制ROC曲线,寻找鉴别宫颈癌和正常宫颈的最佳ADC值截断点。结果正常子宫颈三层结构的弥散图像信号强度有显著性差异,内膜信号最高,肌层次之,结合带最低,两两比较,差异有统计学意义(P0.05);正常宫颈各层ADC值:肌层(1.911±0.305)×10-3mm2/s内膜(1.590±0.311)×10-3mm2/s结合带(1.361±0.203)×10-3mm2/s,两两比较,有显著性差异(P0.05)。宫颈癌ADC值为(0.924±0.110)×10-3mm2/s,低于正常宫颈内膜、结合带、肌层ADC值(t值分别为-7.438,-7.140,-11.221,P=0.000)。以1.120×10-3mm2/s为最佳截断点,鉴别宫颈癌与正常宫颈内膜,敏感性和特异性分别为100%和95.5%。结论宫颈癌与正常子宫颈三层结构DWI和ADC值存在差异,扩散加权成像有助于鉴别正常宫颈和宫颈癌组织。

The Application of Diffusion-weighted Imaging at 3.0T MR in Cervical Cancer

Objective To compare the difference of ADC values between cervical cancer and normal cervical tissue, and to evaluate the value of DWI in diagnosis of cervical cancer. Methods 44 patients with cervical cancer and 20 adult female healthy volunteers were included in this study. MRI examinations were performed preoperatively at a GE 3.0T MR scanner. ADC values of different zones of the normal cervical tissue, as well as diffusion signal intensity in DWI, were compared. The ADC values of tumor were compared with those of the normal cervical tissue.ROC were drawn to analyze the criteria value of ADC, and the sensitivity and specificity were calculated. Results The ADC values of cervical endometrium, conjunctive zone and muscular layer were (1.590±0.311)×10-3mm2/s,(1.361±0.203)×10-3mm2/s and (1.911±0.305)×10-3mm2/s respectively, there were significant differences statistically between the three pairwise(P<0.05). The diffusion signal intensity in DWI of cervical endometrium, conjunctive zone and muscular layer was (268.000±32.901), (148.461±45.051) and (193.846±41.910) respectively, there were significant differences between the three pairwise(P<0.05). Cervical cancer lesion demonstrated obviously hyperintensity on DWI images. The mean ADC value of tumor (0.924±0.110)×10-3mm2/s was statistically lower than that of endometrium, conjunctive zone and muscular layer (P<0.05). A cut-off value of 1.120×10-3mm2/s were used for diagnosis of cervical cancer with a sensitivity of 100%, specificity of 95.5%. Conclusion Both the MR diffusion signal intensity and the ADC values of the normal cervix and tumor were different. MR diffusion weighted imaging may be a useful tool for diagnosis and differential diagnosis of cervical cancer.