Final answer:
A sensitivity test in nuclear medicine measures the concentration of radioactive tracers in the body to diagnose various conditions. Techniques like PET scans and radioimmunoassay (RIA) use radioactive isotopes absorbed by tissues to provide diagnostic information.
Step-by-step explanation:
A sensitivity test in nuclear medicine is a diagnostic tool used to measure the concentration of radioactive tracers within the body. This method utilizes the principles of radioactivity to detect and diagnose various conditions, from cancer to heart disease. One common technique is Positron Emission Tomography (PET) scans, which use radioactive isotopes to create detailed images of internal bodily functions. Radioactive isotopes such as technetium-99, thallium-201, iodine-131, and sodium-24 are selectively absorbed by different tissues, allowing the detection of tissue damage or disease. The radioactivity emitted by the isotopes is measured with specialized detectors, thereby providing important information on the location and extent of the disease.
In the case of a thyroid function test, radioactive iodine-131 uptake by the thyroid gland is measured to diagnose conditions like hyperthyroidism or hypothyroidism. A radioimmunoassay (RIA) is another type of sensitivity test used to precisely measure substances in the body using the principle of competitive binding. RIA is crucial for applications such as cancer screening and hepatitis diagnosis.