Abstract: Objective　To investigate the clinical efficacy and safety of ultrasound-guided microwave ablation in the treatment of high-risk benign thyroid nodules.　Methods　From July 2017 to May 2018, patients with high-risk benign thyroid nodules underwent percutaneous microwave ablation after ultrasound-guided injection of "liquid sequestration belt". Prior to surgery and 6 months after surgery, the length, volume, volume reduction ratio and relevant clinical manifestations of nodules were assessed, including cosmetic and symptomatic scores, thyroid function and thyroid-related antibodies. At the same time, the complications such as toothache, hoarseness and dysphagia were followed up.   Results    A total of 54 patients (49 females and 5 males) with complete follow-up data were enrolled, with an average age of (44.6±11.85) years (20~66 years). The average length and diameter of the initial nodule were (2.90±1.18) cm and decreased significantly to  (1.90±0.94) cm after 6 months(P<0.001). The initial nodule volume was (7.81±8.76) mL and significantly decreased to (2.66±3.23) mL at the last follow-up( P<0.001), with an average reduction of (69.65±15.27)%. The scores of symptoms and cosmetology decreased (P<0.001). There were 2 cases of toothache during the operation. The toothache was relieved after stopping ablation. One case had hoarseness after ablation, but no treatment was given. The voice recovered after 1 month. Intraoperative bleeding occurred in one cases. No patients developed  dysphagia.  Conclusion  Ultrasound-guided percutaneous microwave ablation after injection of "liquid isolation zone" can improve the appearance and symptoms of high-risk benign thyroid patients, and ensure the safety of surgery.       

Key words:  , Ultrasound, 　Microwave ablation, 　Benign nodules, 　Thyroid gland