Radioactive iodine uptake test

The Radioactive Iodine Uptake Test (RIU) is a type of nuclear medicine examination used to assess the functionality of the thyroid gland. The test involves the administration of a small amount of radioactive iodine and the subsequent measurement of how much iodine the thyroid gland absorbs from the bloodstream.

Procedure

The RIU test is performed in two stages. The first stage involves the oral administration of a small amount of radioactive iodine. The second stage, which takes place 24 hours later, involves the measurement of the amount of iodine absorbed by the thyroid gland. This is done using a device called a gamma camera, which can detect the radiation emitted by the iodine and create an image of the thyroid gland.

Uses

The RIU test is primarily used to diagnose conditions that cause hyperthyroidism, such as Graves' disease and toxic multinodular goiter. It can also be used to determine the cause of hypothyroidism, although this is less common.

Risks

The amount of radiation used in the RIU test is very small and is generally considered safe. However, the test is not recommended for pregnant women or those who are breastfeeding, as the radiation could potentially harm the fetus or infant.

See also

• Thyroid function tests
• Thyroid scan
• Thyroid diseases

References

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  Radioactive iodine uptake test
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  Radioactive iodine uptake test