What substances used in radiology that emit radiation?

There are several substances used in radiology that emit radiation, including:

1. X-rays: X-rays are a form of electromagnetic radiation, similar to visible light but with shorter wavelengths and higher energy. They are produced when high-energy electrons are rapidly decelerated, typically by striking a metal target. X-rays are widely used in medical imaging, such as X-ray radiography and computed tomography (CT) scans.

2. Gamma rays: Gamma rays are a form of electromagnetic radiation similar to X-rays but with even shorter wavelengths and higher energy. They are emitted by the radioactive decay of certain atomic nuclei and are used in medical imaging techniques such as gamma scintigraphy and positron emission tomography (PET) scans.

3. Radioactive isotopes: Radioactive isotopes are unstable forms of elements that emit radiation as they decay. They are used in various medical procedures, including nuclear medicine imaging and radiotherapy. Some commonly used radioactive isotopes include iodine-131, technetium-99m, and cobalt-60.

4. Neutrons: Neutrons are subatomic particles with no electrical charge and are found in the nucleus of an atom. They are emitted by certain types of radioactive decay and can be used in imaging techniques such as neutron radiography and neutron computed tomography (nCT).

5. Electron beams: Electron beams are streams of high-energy electrons that are used in radiotherapy to treat cancer. They can be generated by linear accelerators or other particle accelerators.

It's important to note that the use of radiation in radiology is strictly regulated to ensure the safety of patients and healthcare professionals. Medical professionals take precautions to minimize radiation exposure and use appropriate shielding and safety protocols to protect both patients and themselves from unnecessary radiation.