3.0T MRI结合不同b值的DWI对HIFU治疗子宫肌瘤的疗效评估

Evaluation of the Efficacy of 3.0T MRI Combined with DWI with Different b Values on HIFU Treatment of Uterine Fibroids

目的研究3.0T磁共振成像(magnetic resonance imaging,MRI)结合不同b值的扩散加权成像(diffusion weighted imaging,DWI)对子宫肌瘤患者HIFU治疗后疗效评估价值。方法选取72例子宫肌瘤患者,均接受高强度聚焦超声(high intensity focused ultrasound,HIFU)治疗,且于治疗前、治疗后行3.0T MRI检查。观察子宫周围组织MRI信号的变化,分析各b值(150 s/mm^(2)、500 s/mm^(2)、1000 s/mm^(2))时DWI成像下未消融和消融区域表观扩散系数(apparent diffusion coefficient,ADC)的差异,评价ADC值对消融、未消融区域的诊断效能。结果耻骨联合、腹壁术后定量信号值明显高于术前,而骶骨术后定量信号值明显低于术前(P<0.05)。随着b值的增加,子宫邻近组织(腹壁、耻骨联合、骶骨)损伤区HIFU术后的ADC值明显降低(P<0.05)。消融处的ADC值均明显低于术前肌瘤、未消融处的ADC值,且随着b值的增加,术前肌瘤、未消融处以及消融处的ADC值均明显降低(P<0.05)。b=150 s/mm^(2)时,诊断消融部位的ADC值截断值为1.66×10^(-3) mm^(2)/s,AUC为0.883(95%CI 0.846~0.927),其中AUC值高于500 s/mm^(2)、1000 s/mm^(2)。结论3.0T MRI结合不同b值的DWI可有效评估HIFU术对子宫肌瘤的消融效果以及对周围邻近组织的影响,其中较低的b值(b=150 s/mm^(2))具有更高的应用价值。

Objective To study the evaluation value of 3.0T MRI combined with DWI with different b values in the treatment of patients with uterine fibroids.Methods 72 patients with uterine fibroids were treated with high intensity focused ultrasound(HIFU)and underwent 3.0T MRI examination before and after treatment The changes of MRI signals in periuterine tissues were observed,and the differences of ADC values between ablated and non ablated regions in DWI were analyzed when b values were 150,500 and 1000 s/mm^(2).The diagnostic efficacy of ADC value in ablation and non ablation areas were evaluated.Results The quantitative signal value of pubic symphysis and abdominal wall after operation was significantly higher than that before operation,while that of sacrum was significantly lower than that before operation(P<0.05).With the increase of b value,the ADC value of adjacent uterine tissue(abdominal wall,pubic symphysis,sacrum)injury area decreased significantly after HIFU(P<0.05).The ADC values at the ablation sites were significantly lower than those at the preoperative myoma and unablated sites,and with the increase of b values,the ADC values at the preoperative myoma,unablated sites and ablation sites were significantly decreased(P<0.05).The ADC cut-off value for the diagnosis of ablation sites at b=150 s/mm^(2) was 1.66×10^(-3) mm^(2)/s and the AUC was 0.883(95%CI 0.846b=0.927),of which the AUC value was higher than that of b=500 s/mm^(2),1000 s/mm^(2).Conclusion 3.0 T MRI combined with DWI of different b values can effectively evaluate the ablation effect of HIFU surgery on uterine leiomyoma and the effect on surrounding adjacent tissues,among which lower b values(b=150 s/mm^(2))have higher application value.