Imaging manifestation of gray-scale ultrasonography in ultrasound-guided percutaneous microwave ablation for uterine fibroid and adenomyosis and its clinical significance

Abstract

Objective To investigate the imaging manifestation and clinical significance of gray-scale ultrasonography during and after ultrasound-guided percutaneous microwave ablation (PMWA) for benign uterine myometrium lesions. Methods A total of 588 patients, 255 with leiomyomas and 333 with adenomyoma, who underwent PMWA between August 2007 and June 2015 were studied. The echo and blood supply characteristics of the lesions were observed with gray-scale ultrasonography before ablation and 3, 6, 9, 12, 24 months after ablation. During the ablation, the echo range of the ablated area was monitored with ultrasonography. Results A total of 588 cases was included in the study, including 255 uterus fibroid cases and 333 adenomyosis cases. In the process of ablation, gray scale ultrasound presented as diffused hyper-echo from the seam of microwave electrode. The range of hyper-echo gradually increased as along with the time of ablation, until the ablation stopped. The ablation area showed hyperecho without color signal immediately after PMWA, and no contrast agent perfusion by contrast-enhanced ultrasonography. As the follow-up time was prolonged, the echo of ablation area was gradually decreased, and became not homogeneous. Echoless area was showing after 3 months, and disappeared gradually after 12 months. The ablation needle tracks presented as hyperechoic strips and were still visible after 24 months. Conclusions The imaging characteristics of gray-scale ultrasonography during and after PMWA are so featured that it can monitor the ablation process in real time, and evaluate the outcome of lesions in the late stage. Key words: Ultrasonography; Leiomyoma; Adenomyoma; Microwaves; Catheter ablation