Thyroid function test

1. Measurement of plasma TSH concentration.

TSH	Condition
High	Primary hypothyroidism
Low	Secondary hypothyroidism
Very low	hyperthyroidism

  

2. Measurement of plasma thyroid hormone concentration.

Generally thyroid hormone decreases in hypothyroid and increases in hyperthyroid state.

3. Radioactive iodine uptake test.

RAIU test status	Thyroid status
Low uptake	Hypothyroid
High uptake	Hyperthyroid
5-15% uptake at 6th hours 8-30% uptake at 24th hours	Euthyroid

  

4. Measurement of thyroid autoantibody (eg. Anti-TPO antibody, anti-thyroglobulin antibody, TSH receptor blocking antibody)

5. TSH stimulation test.

6. T₃ suppression test.

7. Thyroid scanning

8. Ultra sonogram of thyroid gland.