Using Radioactive Substances to Diagnose Disease

Nuclear body scanning uses a small amount of radioactive materials to produce images that can distinguish between healthy and abnormal tissues. The images are similar to the ones produced by X-rays the difference is that X-rays originate outside the body while radiation originates from sources that are injected into the body, swallowed, or inhaled. 

One of the most common radionuclides medical technicians use is technetium-99m. 

Lung scans are similar, except the radioactive material is inhaled. For liver scans, radioactive materials are injected into the body. As they pass through the fiver, abnormal cysts or tumors will show up in the images. 

Since iodine concentrates in the thyroid gland, a scan of the thyroid is conducted using a radioactive isotope of iodine, 1-131, which has a half-life of 8.0 days. The iodine sample can be administered by swallowing a capsule or Uquid. Only a small amount of radioactive iodine is used for the procedure, and after a week the level of radioactivity is negligible. Iodine-131 can also be administered to treat goiters. 

Other radionucUdes that are used in medical diagnosis include the following  

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