Abstract

Objective: To investigate the application value of acoustic radiation force impulse imaging in preoperative prediction for efficacy of High-Intensity Focused Ultrasound uterine fibroids ablation

Methods: A prospective study was conducted on 32 women (41 fibroids) undergoing HIFU uterine fibroids ablation between January 2019 and September 2019. The virtual touch tissue quantification (VTQ) technique was used for the preoperative determination of uterine fibroids shear wave velocity (SWV). The stiffness of the preoperative uterine fibroids was graded on a virtual touch tissue image (VTI). All uterine fibroids were ablated with a single point ablation acoustic power of 400 W. All patients underwent pelvic cavity MRI examination for the measurement of the size, volume and non-perfused volume (NPV) of fibroids within the first month after HIFU ablation. The ablation rate of uterine fibroids was calculated according to the formula: ablation rate = NPV × 100/target fibroid volume. The patients were divided into two groups based on the postoperative ablation rate: ≥70% ablation rate group, and＜70% ablation rate group. The preoperative SWV and VTI grade of uterine fibroids were compared between the two groups. The correlation of preoperative uterine fibroids’ SWV and VTI grade with HIFU ablation rate were analyzed using the Spearman’s correlation coefficient. The optimal cutoff points in preoperative uterine fibroids SWV of 70% ablation rate were determined by receiver operating curve (ROC) analysis.

Results: A total of 30 patients (73.17%, 30/41) showed ablation rate ≥70%, with preoperative uterine fibroids’ SWV values of (3.42 ± 0.71) m/s. Of these, 24 patients (80%, 24/30) had VTI grades II–III. On the other hand, 26.83% (11/41) showed ablation rate <70%, with preoperative uterine fibroids’ SWV values of (4.02 ± 0.69) m/s; of these, 63.6% (7/11) had VTI grade IV. The SWV values and VTI grades of preoperative uterine fibroids were significantly different in the two groups (p < 0.05). Interestingly, postoperative ablation rate was negatively correlated with preoperative uterine fibroids’ SWV values (r= −0.536, p = 0.0003) and VTI grades (r= −0.511, p = 0.001). The area under the ROC curve of preoperative uterine fibroids’ SWV values with ablation rate <70% was 0.75 at a cutoff value of 3.915 m/s (p < 0.05). Specificity was 72.7% and sensitivity was 80.1%; the positive predictive value was 72.7%, and the negative predictive value was 80%.

Conclusion: ARFI technique is an effective and feasible noninvasive ultrasound technique for the preoperative prediction of the efficacy of HIFU uterine fibroids ablation.

摘要

目的：探讨声辐射力脉冲成像在术前预测高强度聚焦超声子宫肌瘤消融疗效中的应用价值

方法：在2019年1月至2019年9月之间，对32例进行HIFU子宫肌瘤消融的女性（41例肌瘤）进行了一项前瞻性研究。虚拟触摸组织定量（VTQ）技术用于术前确定子宫肌瘤的剪切波速度（SWV）。术前子宫肌瘤的硬度在虚拟触摸组织图像（VTI）上分级。所有子宫肌瘤均采用400 W单点消融声功率消融。所有患者均在HIFU消融后的第一个月内接受盆腔MRI检查，以测量肌瘤的大小，体积和非灌注体积（NPV）。根据以下公式计算子宫肌瘤的消融率：消融率= NPV×100 /目标肌瘤体积。根据术后消融率将患者分为两组：消融率≥70％组和消融率<70％组。比较两组术前子宫肌瘤的SWV和VTI分级。利用Spearman相关系数分析术前子宫肌瘤SWV和VTI等级与HIFU消融率的相关性。通过接受者工作曲线（ROC）分析确定术前子宫肌瘤SWV消融率为70％的最佳临界点。

结果：共有30例患者（73.17％，30/41）消融率≥70％，术前子宫肌瘤的SWV值为（3.42±0.71）m / s。在这些患者中，有24例（80％，24/30）具有VTI II–III级。另一方面，有26.83％（11/41）的消融率<70％，术前子宫肌瘤的SWV值为（4.02±0.69）m / s。其中63.6％（7/11）的患者达到VTI IV级。两组术前子宫肌瘤的SWV值和VTI等级显着不同（p  <0.05）。有趣的是，术后消融率与术前子宫肌瘤的SWV值（r = − 0.536 ，p =  0.0003）和VTI分级（r = − 0.511 ，p =  0.001 ）呈负相关。切除率＜70％时，术前子宫肌瘤SWV值在ROC曲线下的面积为0.75，截止值为3.915 m / s（p <  0.05）。特异性为72.7％，敏感性为80.1％；阳性预测值为72.7％，阴性预测值为80％。

结论： ARFI技术是一种术前预测HIFU子宫肌瘤消融疗效的有效，可行的无创超声技术。