A PET-CT scan is a nuclear medicine test of the whole body. It shows active tissue such as cancer, infection or inflammation. Typical effective dose 10 to 25 mSv, similar to about 3 to 8 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.
A PET-CT scan is a medical imaging test that uses a radioactive substance called a tracer to create detailed images of the body. It helps doctors see active tissue such as cancer, infections, or inflammation. The typical effective radiation dose is 10 to 25 mSv, which is similar to about 3 to 8 years of natural background radiation. The test is often used to stage cancer or assess its response to treatment. Before the scan, patients need to fast for 4 to 6 hours, and those with diabetes should follow special instructions about sugar and insulin. Pregnant women should inform the staff, as the risk is small but can be mitigated with shielding or alternative imaging techniques. The scan takes about 2 to 3 hours and results must be interpreted by a qualified health professional.
Active tissue such as cancer, infection or inflammation.
Cancer staging and response to treatment.
Fast 4 to 6 hours; diabetes needs special instructions about sugar and insulin; avoid hard exercise the day before.
Typical effective dose 10 to 25 mSv, similar to about 3 to 8 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.
2 to 3 hours. 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 pet ct show?
Active tissue such as cancer, infection or inflammation.
Why is a pet ct done?
Cancer staging and response to treatment.
How do I prepare for a pet ct?
Fast 4 to 6 hours; diabetes needs special instructions about sugar and insulin; avoid hard exercise the day before.
Does a pet ct use radiation?
Typical effective dose 10 to 25 mSv, similar to about 3 to 8 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 pet ct take?
2 to 3 hours
Why is PET-CT scan done?
Cancer staging and response to treatment.
How do I prepare for PET-CT scan?
Fast 4 to 6 hours; diabetes needs special instructions about sugar and insulin; avoid hard exercise the day before.
Is PET-CT scan safe in pregnancy?
Typical effective dose 10 to 25 mSv, similar to about 3 to 8 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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