zara woollard
9.1 | 2019
radioisotopes in
nuclear medicine
what is nuclear medicine?
Nuclear medicine is the use of radioisotopes to treat and diagnose diseases. There are two main uses of radiation that constitute as nuclear medicine. One is the introduction of a radioactive substance, either given intravenously or orally, into the human body. This makes you radioactive for usually a short amount of time. Doctors use radioisotopes with short half lives to minimise the amount of radiation exposure a person will experience. Radiation occurs inside the body. This radiation is recognised by a scintillation crystal in a "gamma camera" which is the tube a person goes into. These scintillation crystals convert the radioactive signals into a faint light, which is then digitalised, and converted into a 3D image, which can be used to diagnose many diseases. There are four variations of this branch of nuclear medicine: Positron Emission Tomography (PET scans), Single Photon Emission Computed Technology (SPECT), Cardiovascular imaging, and bone scans.
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The other use of radiation in nuclear medicine is to fight cancer, because the high frequency of gamma rays can damage the DNA of cancer cells. This is called teletherapy. Depending on it's nature, radiotehrapy can be either brachytherapy, or teletherapy. Brachytherapy is internal, and teletherapy is external.
how it relates to nuclear energy and radioactivity:
Nuclear medicine uses radioactive substances, (radioisotopes) to treat and diagnose problems within the human body. The nuclear energy created by gamma decay can damage cells of cancer, and they can also be converted into images so doctors can diagnose diseases or problems in the body.
difference between x-rays and nuclear medicine:
An X-ray, or a CT scan is different from nuclear medicine because of how the radiation is created. For an X-ray, electrons must either rearrange in an atom, or strike a target, compared to nuclear medicine practices where radiation is emitted because of an excited nucleus. PET scans can be better than CT scans because they detect diseases on a cellular level, and can diagnose in the crucial stages.
Radiotherapy - fighting cancer
Radiotherapy is a branch of nuclear medicine, which deals with fighting cancerous cells. Radiotherapy involves having gamma rays directed at a tumour. Brachytherapy is a form of radiotherapy, where a patient swallows a solid radioisotope, which locally targets a tumour.
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IMAGE 8: Radiotherapy to Treat Cancer
