Inclusion Criteria:

1. the presence of subjective symptoms (foreign body sensation, neck discomfort or pain,
compressive symptom) or cosmetic problems;

2. a poor surgical candidate or refusal to undergo surgery;

3. fine-needle aspiration cytology and US findings that were compatible with a benign
nodule;

4. anxiety about a malignancy.

Exclusion Criteria:

1. a nodule less than 5 mm in size;

2. follicular neoplasm or malignancy on fine needle aspiration cytology (FNAC);

3. a nodule with the sonographic criteria for a malignancy (taller than wide, marked
hypoechoic, microcalcifications, ill-defined margins), although FNAC was a benign
result;

4. previous radiation or operation history to the head and neck; (5) previous sclerosing
therapy.