1. Serum TSH, T3, T4 test
Serum TSH, T3, T4 levels are normal in patients with simple goiter.
2. Iodine 131 uptake rate
Iodine 131 uptake rate is normal or elevated.
3. Serum TPOAb, TgAb
Generally negative, a few may be mildly elevated, which may suggest a greater likelihood of hypothyroidism in the future.
4. Fine-needle aspiration cytology
Fine-needle aspiration cytology should be performed for hyperechoic nodules on ultrasound, calcified nodules ≥1mm in diameter, hard nodules, or fast-growing nodules. Fine-needle aspiration cytology is the most effective method of evaluating the benignity or malignancy of thyroid nodules before surgery, with sensitivity ranging from 65% to 98%, and specificity ranging from 72% to 100%. ～The sensitivity is 65% to 98% and the specificity is 72% to 100%.
5. Neck X-ray examination
Tracheal X-ray should be taken for patients with long course of disease, obvious thyroid enlargement, or symptoms of respiratory obstruction or retrosternal goiter, in order to find out whether there is any tracheal displacement, tracheal tenderness, and to determine the location and size of retrosternal goiter.
6. Neck ultrasound
Neck ultrasound is a convenient and reliable method to diagnose goiter.Ultrasound is able to detect small nodules of 2-4mm, so ultrasound can find nodules that cannot be touched by physical examination.Usually, physical examination reveals that the incidence of thyroid nodules in adults is 4-7%, while ultrasound reveals that nearly 70% of adults have thyroid nodules.
Color Doppler examination, can be found in the normal thyroid blood flow signal is not significantly increased, showing scattered little blood flow signal.
7. Nuclide imaging
Nuclide imaging can evaluate the morphology of the thyroid gland and the function of the thyroid nodules. Diffuse goiter is seen as an enlarged thyroid with a uniform distribution of radioactivity, and nodular goiter is seen as hot or cold nodules.
8. CT and MRI of the neck
CT or MRI of the neck do not provide more information than ultrasound and are more expensive, but they have high diagnostic value in retrosternal goiter.
9. Respiratory function tests
Lung function tests should be performed in giant goiter or retrosternal goiter to make a functional assessment of airway compression.