I. Technical Introduction
The traditional treatment of thyroid nodules is surgical resection. Image-guided percutaneous radiofrequency ablation technology is a new method of tumor treatment carried out at home and abroad in recent years. This technology is based on implanting water-cooled ablation electrodes 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, thus achieving the purpose of minimally invasive local inactivation of the lesion.
Ultrasound-guided radiofrequency ablation for thyroid nodules is a safe and effective method. This technique was pioneered and reported by Dr. Baek in Korea, and the final lesion absorption rate was 84,11±14,93% without serious complications. It is confirmed that radiofrequency ablation is a safe and effective method for treating thyroid nodules. Currently, there are two modes of radiofrequency ablation of thyroid nodules, namely MovingShot (continuous moving ablation) mode and conventional ablation mode.
MovingShot mode can ablate while moving the ablation electrode, which can achieve rapid inactivation of nodules with fewer punctures in the treatment of large thyroid nodules.
Indications
(1) Benign thyroid nodules that meet the following conditions.
(1) Nodule diameter greater than 2 cm;
(2) Subjective symptoms, such as neck discomfort or pain, difficulty in breathing or swallowing, etc;
③Aesthetic needs;
(4) Poor general condition that cannot tolerate surgery or refuses surgery.
(2) 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 of patients.
Contraindications
(1) Coagulation mechanism disorder, serious bleeding tendency, and serious cardiopulmonary disease that cannot tolerate the treatment are still considered as contraindications.
(2) Relative contraindications.
①Nodules less than 2 cm;
(2) Puncture biopsy results of follicular or malignant tumors;
(3) Although the biopsy result is benign, the ultrasound sonogram is highly malignant (longer diameter than wide diameter, significant hypoechogenicity, microcalcifications inside, unclear boundary, etc.).
IV. Preoperative preparation
1. Imaging examination: ultrasound or ultrasonography, etc. In order 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 who have bleeding tendency, vitamin K or Lizhixue should be used 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 (radiofrequency) 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 (radiofrequency) treatment and the possible complications during and after treatment and their countermeasures.
IV. Complications and management
Radiofrequency ablation treatment of thyroid tumor is a safe and effective method with low incidence of complications, the common complications are
1. Burning sensation and pain in the neck: it is a common complication, sometimes radiating to the head, teeth, shoulders and chest.
2, fever: rare, mainly the body’s reaction to radiofrequency high temperature fever and the absorption of necrotic tissue fever, symptomatic treatment can subside.
3, extra-thyroidal hematoma: the incidence of about 2, 1%, mostly disappears within a month.
4.Returning laryngeal nerve injury: a more serious complication with an incidence of about 1.3%. It can be avoided by ablation in several times.
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.).