A Whole-body iodine scan (thyroid cancer) is a nuclear medicine test of the whole body. It shows remaining thyroid tissue or spread after thyroid cancer surgery. Typical effective dose 1 to 5 mSv, similar to about 4 months to 2 years of natural background radiation (about 3 mSv a year).
General health information, not a diagnosis. In an emergency, call 102. Always consult a qualified health professional.
Remaining thyroid tissue or spread after thyroid cancer surgery.
Thyroid cancer follow-up.
A small radioactive tracer is injected or swallowed. Preparation depends on the test; tell staff if pregnant or breastfeeding, as feeding may need a pause.
Typical effective dose 1 to 5 mSv, similar to about 4 months to 2 years of natural background radiation (about 3 mSv a year). Tell staff if you are or might be pregnant; the benefit usually outweighs the small risk, and shielding or alternatives can be considered.
1 to 2 hours on day 2 to 3. General information, not a diagnosis. Results must be interpreted by a qualified health worker.
Nuclear medicine
Consult a doctor to interpret results — a single test does not make a diagnosis.
Uses your location once to list the nearest facilities. Nothing is stored.
What does a i131 scan show?
Remaining thyroid tissue or spread after thyroid cancer surgery.
Why is a i131 scan done?
Thyroid cancer follow-up.
How do I prepare for a i131 scan?
A small radioactive tracer is injected or swallowed. Preparation depends on the test; tell staff if pregnant or breastfeeding, as feeding may need a pause.
Does a i131 scan use radiation?
Typical effective dose 1 to 5 mSv, similar to about 4 months to 2 years of natural background radiation (about 3 mSv a year). Tell staff if you are or might be pregnant; the benefit usually outweighs the small risk, and shielding or alternatives can be considered.
How long does a i131 scan take?
1 to 2 hours on day 2 to 3
Why is Whole-body iodine scan (thyroid cancer) done?
Thyroid cancer follow-up.
How do I prepare for Whole-body iodine scan (thyroid cancer)?
A small radioactive tracer is injected or swallowed. Preparation depends on the test; tell staff if pregnant or breastfeeding, as feeding may need a pause.
Is Whole-body iodine scan (thyroid cancer) safe in pregnancy?
Typical effective dose 1 to 5 mSv, similar to about 4 months to 2 years of natural background radiation (about 3 mSv a year). Tell staff if you are or might be pregnant; the benefit usually outweighs the small risk, and shielding or alternatives can be considered.
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