Fig. 6

A 50-year-old female patient with ZTTN (white arrow) in the right lobe underwent US-guided MWA. The surgeon was on the side of the patient’s head during the procedure. (A) Two ZTTNs (white arrow) were closely related to the RLN (asterisk) in the short axial section. The distance from the farthest outside of ZTTNs (white arrow) to the outer edge of thyroid is 5.0 mm (ZTTN grade 2). (B) In the long axial section, one of the ZTTN (white arrow) was observed closely related to the RLN (asterisk). The RLN (asterisk) was located at the back of the ZTTN (white arrow), and the relationship between ZTTN and RLN was Type A. (C) The contrast-enhanced ultrasound showed high enhancement of ZTTN (white arrow) and RLN (asterisk). (D) After the hydrodissection began, the ZTTN (white arrow) could be seen to separate from the RLN (asterisk). (E) To ablate the superficial ZTTN, the injection needle (long white arrow) was placed between the ZTTN (white arrow) and the RLN (asterisk). (F) After continuous injection of physiological saline solution, the distance between the RLN (asterisk) and ZTTN (white arrow) was significantly widened. (G) The ablation antenna (double white arrows) was inserted into the superficial ZTTN (white arrow). (H-I) During MWA, the ablation antenna (double white arrows) was tilted upward to increase the distance between ZTTN and the RLN (asterisk). (J) Contrast-enhanced ultrasound after MWA showed that the ZTTN (white arrow) was not enhanced, indicating that the ZTTN was completely ablated. The RLN (asterisk) was highly enhanced, and the patient’s voice did not change significantly after MWA, indicating that the patient’s RLN was not damaged during MWA