子宫肌瘤超声消融后早期子宫浆肌层损伤的MRI评价

Magnetic resonance imaging-based assessment of seromuscular layer injuries early after ultrasound ablation of uterine fibroids

目的研究子宫肌瘤超声消融后子宫浆肌层损伤的早期MRI影像学特征及损伤发生情况。方法选择2013-2017年在重庆医科大学附属第一医院接受高强度聚焦超声(high intensity focused ultrasound, HIFU)消融治疗子宫肌瘤且术前、术后MRI资料完整的患者671例,其中符合纳入标准的有400例。根据术后3 d内的MRI图像,造影剂注射后120 s内始终无强化确定为损伤,观察损伤的形态特点并测量其范围。结果子宫肌瘤所在肌壁的浆肌层无损伤表现为完整的环状强化,有损伤表现为强化局部缺损。浆肌层损伤者90例(22.50%),浆肌层损伤范围为3.9~66.3(25.9±14.8)mm。子宫肌瘤体积消融率为(86.91±17.78)%,高于未发生浆肌层损伤者[(80.93±16.25)%,P<0.05];子宫浆肌层损伤多发生于声通道的前场,也可发生于近骶骨的位置。浆膜下肌瘤浆肌层损伤发生率(43.09%)高于肌壁间肌瘤(14.18%,P<0.05),且浆膜下肌瘤子宫浆肌层损伤范围[(26.8±15.5)mm]高于肌壁间肌瘤[(24.6±14.0)mm]。患者均未发生严重并发症。90例子宫浆肌层损伤患者中,均无阴道持续出血、血尿、血便等表现。HIFU术后3、6个月随访MRI,显示子宫浆肌层强化完整。结论子宫肌瘤超声消融后早期会出现MRI可见的子宫浆肌层损伤,且损伤位置多发生与声通道的前场,未出现相关临床不良反应。

Objective To investigate the magnetic resonance imaging(MRI) features of uterine seromuscular layer injuries early after ultrasound ablation of uterine fibroids. Methods Between 2013 and 2017, a total of 671 women received high-intensity focused ultrasound(HIFU) ablation of uterine fibroids in the First Affiliated Hospital of Chongqing Medical University and underwent MRI examinations both before and after the ablation. After screening for eligibility, 400 patients were enrolled in this study. Uterine seromuscular layer injuries following HIFU were defined as the presence of non-perfused area within 120 s after contrast medium injection on enhanced MRI images within 3 d after HIFU. The morphological features and extension of the injuries were analyzed in these patients. Results The uterine seromuscular layer without injuries showed intact circular enhancement on MRI, and injuries were manifested as local enhancement deficits. Of the 400 cases included in this analysis, 90(22.50%) showed seromuscular layer injuries following HIFU, and the lesions ranged from 3.9 mm to 66.3 mm in size(mean 25.92±14.84 mm);the valume ablation rate was significantly higher in cases with seromuscular layer injuries than in cases without injuries [(86.91±17.78)% vs(80.93±16.25)%, P<0.05]. The seromuscular layer injuries occurred most frequently in the anterior field of the acoustic pathway and occasionally in the proximal sacrum. The incidence of seromuscular layer injuries was significantly higher in cases of subserosal fibroids than in cases of intramural myoma(43.09% vs 14.18%, P<0.05), and the size of lesions was greater in the former cases(26.8±15.5 vs 24.6±14.0 mm). No major complications occurred in these patients following the ablation. None of the 90 patients with seromuscular layer injuries had persistent vaginal bleeding, hematuria, or hematoplegia, and follow-up MRI at 3 and 6 months after HIFU showed complete enhancement of the seromuscular layer in all these cases. Conclusion Seromuscular layer injuries visible on MRI can occur early after ultrasound ablation of uterine fibroids, and the injury sites locate often in the anterior field of the acoustic pathway but do not cause significant clinical adverse reactions.