The traditional treatment of thyroid nodules is surgical excision, which leaves obvious scars on the neck after surgery. Image-guided percutaneous microwave ablation technology is a new method of tumor treatment carried out at home and abroad in recent years. The technology is to puncture the water-cooled ablation microwave knife into the lesion under ultrasound guidance, causing coagulative necrosis of the lesion tissue through high-temperature heating, and finally the necrotic tissue is absorbed by the body, so as to achieve the purpose of minimally invasive local inactivation of the lesion. Ultrasound-guided microwave ablation is a safe and effective method for the treatment of thyroid nodules, with a final lesion absorption rate of 84.11±14.93% and no serious complications. It is confirmed that microwave ablation is a safe and effective method to treat thyroid nodules. Indications Benign thyroid nodules with the following conditions: (1) nodules larger than 1 cm in diameter; (2) subjective symptoms, such as neck discomfort or pain, difficulty in breathing or swallowing; (3) aesthetic needs; (4) poor general condition unable to tolerate surgery or refusing surgery. For patients with recurrent thyroid malignant tumors who have lost the opportunity to undergo surgery, radiotherapy and chemotherapy, ablation can be used to destroy the lesions to achieve the purpose of tumor destruction or reduction, thus improving the quality of life and prolonging the survival period. Contraindications Coagulation disorders, serious bleeding tendency, and serious cardiopulmonary diseases that cannot tolerate the treatment are still considered as contraindications. Relative contraindications: ① solid nodule component greater than 5cm; ② puncture biopsy results of follicular or malignant tumor; ③ ultrasound sonogram shows high malignancy (long diameter greater than wide diameter, significant hypoechogenicity, microcalcifications inside, unclear boundary, etc.). Preoperative preparation 1. Imaging examination: ultrasound or ultrasonography, etc. To understand in detail the location, shape, size, blood supply inside and around the nodule and the relationship between the nodule and the surrounding structures, and to determine the best needle site and route. 2. Other examinations: chest X-ray and electrocardiogram. Echocardiography, 24-hour ambulatory electrocardiogram and pulmonary function should be checked for combined cardiopulmonary diseases. 3.Blood tests: serum four, coagulation function, thyroid function, blood calcium, etc. For those with bleeding tendency, use vitamin K or lithotripsy before and after surgery. 4.Puncture biopsy. Pre-operative ultrasound-guided 18G needle aspiration biopsy to obtain lesion specimens for clear pathological diagnosis, or aspiration biopsy before microwave ablation treatment during surgery. 5. Sign the informed consent for surgery. Follow the principle of informed consent, explain the condition to the patient or family before treatment and introduce the significance of microwave therapy and the possible complications during and after treatment and their countermeasures. V. Complications and treatment Microwave ablation for thyroid tumor is a safe and effective method with low complication rate. The common complications are: 1. 2, fever: rare, mainly due to the body’s reaction to the high temperature of the microwave fever and the absorption of heat on necrotic tissue, symptomatic treatment can subside. 3, extra-thyroidal hematoma: the incidence of about 2.1%, mostly disappeared within a month. 4.Returning laryngeal nerve injury: a more serious complication with an incidence of about 1.3-3.3%. Fractional ablation can be avoided. 5.Thyroid function abnormalities: rare and mild, no need for medication, usually found in a week, and normalized after one month. 6.Other complications: rare, such as infection, important structural damage (including the skin of the larynx, trachea, esophagus, blood vessels, etc.).