Radiation is the transmission or traveling of the energy through space or a material medium in the form of waves or particles. Ultraviolet radiation from the Sun is the most familiar form of radiation that we know. Except for the UV radiation, there are some higher-energy kinds of radiation, collectively known as Ionizing Radiation (such as α, β, or γ radiation) that are present on Earth and we all are exposed to it in minute doses through rock, soil, space, and air. But exposure to the higher levels of such radiation is harmful and dangerous and thus, the exposure should be controlled. The use of radiation in the medical field has made a huge evolution. Today, about one-third of the entire medical specialties involve radiation or radioactivity, right from the diagnosis - to the treatment.
- In general radiology, the X-rays enters the body from the outside source through space and creates a fixed or still image of the body, while in Nuclear medicine; a small amount of radioactive material (radiotracers, or radiopharmaceuticals) is administered internally, via injection, swallowing or inhalation inside the body into the bloodstream. This radioactive material travels through the area to be examined and produces γ-rays which are detected by the computers to create images.
- The traditional imaging systems of radiology (X-rays, Ultrasound, CT scans, MRI) creates only a fixed or still image of the body showing the anatomy or structure of the body, while the nuclear imaging techniques (PET, SPECT) show the physiological function of the area to be investigated by producing two-dimensional or three-dimensional images.
- In addition, through Nuclear medicine imaging techniques, a specific organ or tissue can be examined such as brain, lungs, and heart, unlike in general radiology imaging procedures where it produces the image of the whole area such as the chest cavity or abdominal cavity.
- Both of these medical imaging specialties are used to diagnose and determine the severity of the disease and are involved in their effective treatment.
- These imaging procedures are non-invasive or have the minimal invasion, less risk, a shorter recovery time and are less painful than the surgical treatments.
As with all the medical procedures, radiation techniques also involve a level of risk but the benefits are significantly greater than any risk involved.
- Exposure to the radiation in such techniques carries with it a minute increase in the risk of developing cancer later in life, especially to the radiologists and physicians.
- In nuclear medicine, there is a small level of risk associated with the radiotracers administered into the body such as allergic reactions which are very rare as the type of the radioactive materials used by the specialist, depends on the medical history of the patient.