RFA technique

RFA of the hyperplastic parathyroid glands was performed using a radiofrequency generator (Taishanglide, Mianyang, China) with an 18-gauge monopolar, internally cooled electrode (Taishanglide). The radiofrequency electrode shaft length was 7 cm with a 0.7 cm active tip. The radiofrequency electrode was cooled by a water circulation pump. Before ablation, CEUS was used to confirm the parathyroid gland blood supply and the ablation route was also determined. Routine disinfection and draping were performed. Under ultrasound guidance, 1% lidocaine was injected to achieve superficial nerve block anesthesia of the neck. Saline was injected around the parathyroid gland under ultrasound guidance, and a separation zone with a thickness of at least 5mmwas established to separate the gland from the surrounding tissues. The ablation needle was punctured into the parathyroid gland, and the ablation was carried out by gradually withdrawing the needle from the lower pole of the posterior margin of the hyperplastic gland. The total ablation was superimposed on the ablation area to cover all of the glands [9]. One side of the parathyroid gland was ablated intra-operatively and no symptoms related to recurrent laryngeal nerve injury were noted. Then, the other parathyroid gland was ablated.