Compared with traditional treatment methods, ultrasound-guided thermal ablation is more targeted, less invasive and more reliable. The study compared microwave ablation and radiofrequency ablation to evaluate the efficacy and safety in the treatment of benign thyroid nodules with a multicenter data, which will provide a basis for clinical treatment.

Ultrasound-guided minimally invasive treatment has accurate positioning, higher targeting, no need for general anesthesia, less trauma for patients, and more reliable efficacy.Currently, it mainly includes percutaneous anhydrous ethanol injection, radiofrequency ablation and microwave ablation for the treatment of thyroid nodules.Currently, radiofrequency ablation and microwave ablation are mainly used to treat thyroid nodules.

This study was a randomized, parallel, positive control, and non-inferiority multicenter clinical study.Radiofrequency ablation was used as the positive control.Follow-up was conducted at 1, 3, 6 and 12 months after ablation. The primary endpoint was the rate of nodule volume reduction at 12 months after surgery.

Inclusion Criteria:

• Age>18 years and ≤75 years
• The pathological diagnosis was benign thyroid nodules within 6 months
• Diameter ≥2cm, solid > 80%, the number of multiple nodules≤ 3
• Participate voluntarily and sign the informed consent

Exclusion Criteria:

• Coagulation mechanism disorder or bleeding tendency
• Patients with severe cardiopulmonary insufficiency
• Blood pressure cannot be effectively controlled
• abnormal liver function
• Blood glucose cannot be effectively controlled
• Abnormal thyroid function
• Allergic history of ultrasound contrast agent
• Suspicious lymph node metastasis in the cervical region
• Abnormal contralateral vocal cord function
• Pregnant and lactating women
• Have participated in clinical trials of any drug and/or medical device within 3 months prior to enrollment
• The researchers believe that there are any other factors that are not suitable for inclusion or that affect participants' participation in the study.
• Patients with inner pacemaker, hearing aid, metal stent, titanium clip, internal (external) steel plate and other metal objects.