DWI在HIFU消融治疗子宫肌瘤术后评价中的应用

Application of DWI in assessing effect of high intensity focused ultrasound ablation for uterine fibroids

目的探讨DWI在高强度聚焦超声（HIFU）消融治疗子宫肌瘤术后评价中的应用价值。方法对270例患者（共270个子宫肌瘤）行HIFU消融治疗,于术前及术后分别行增强磁共振成像（CE-MRI）及DWI检查,其中A组98例术后MRI于消融当日（术后6h内）完成,B组172例术后MRI于消融后1-2天（24-48h）完成。分析病灶ADC值变化,观察DWI特征。并测量DWI信号改变区体积及CE-MRI无灌注区体积（NPV）,分析二者间的相关性。结果 DWI示HIFU消融后子宫肌瘤呈靶环样改变。两组患者消融前子宫肌瘤ADC值差异无统计学意义（t=-0.322,P=0.748）,消融后ADC值差异有统计学意义（t=8.874,P〈0.001）。A组术后ADC值较术前减低（t=3.500,P=0.001）,B组术后ADC值较术前增高（t=-16.842,P〈0.001）。HIFU消融后DWI信号改变区中位体积为50.78cm3（四分位间距30.03-89.60cm3）,CE-MRI的NPV为52.65cm3（四分位间距30.03-89.60cm3）,差异无统计学意义（z=-1.357,P=0.175）,且二者呈正相关关系（r=0.989,P〈0.001）。结论 DWI可用于HIFU消融治疗子宫肌瘤术后短期疗效的评价。

Objective To investigate the application value of DWI in assessing the treatment effect of uterine fibroids after high intensity focused ultrasound（HIFU）ablation.Methods A total of 270 patients with uterine fibroids（270lesions）underwent HIFU ablation were divided into two groups.Pre-treatment and post-treatment imaging data were obtained using contrast-enhanced MRI（CE-MRI）and DWI.There were 98 cases in group A,who underwent MR examinations within 6hours after ablation,and 172 cases in group B,who underwent MR examinations within 24—48 hours after ablation.The features of DWI and the changes of apparent diffusion coefficient（ADC）value were observed and analyzed.The volume of DWI signal intensity transform and CE-MRI non-perfused volume（NPV）were measured and compared.And the correlation between NPV and the volume of DWI signal intensity transform was studied.Results DWI signal of ROI after HIFU ablation liked a target.No statistical difference of ADC value was found before HIFU ablation between the two groups（t=-0.322,P=0.748）.While there was significant difference of ADC value after HIFU ablation（t=8.874,P〈0.001）.In group A,the ADC value was decreased after HIFU ablation than before（t=3.500,P=0.001）.While the ADC value was increased after HIFU ablation than before in group B（t=-16.842,P〈0.001）.The middle volume of DWI signal intensity transform was 50.78 cm3（interquartile range 30.03—89.60 cm3）.And the middle NPV was 52.65cm3（interquartile range 30.03—89.60cm3）.No statistical difference was found between the volumes measured by DWI and CE-MRI（Z=-1.357,P=0.157）.Moreover,the volume of DWI signal intensity transform correlated positively with NPV（r=0.989,P〈0.001）.High correlation was observed in volume of the ablation area between DWI and CEMRI with Spearmananalysis.Conclusion DWI can be used to assess the effect of HIFU ablation for uterine fibroids.