Scintigraphy is an imaging procedure that plays a decisive role in nuclear medical diagnostics. To create an image, a so-called scintigram, the patient is administered radioactively marked substances. These substances emit radiation and can then be detected by gamma camera in the corresponding organ or tissue.
With the help of a radioactive substance, tissue or organs can be specifically examined. The patient is injected with radioactive material for this purpose. The patient can either be injected directly or administered orally as tablets.
Depending on which tissue or organ is to be examined, different materials are suitable. For example, there are substances that accumulate particularly well in bone tissue. This substance, which is specific to one tissue, is called a tracer.
For example, there is a radioactive iodine particle for the examination of the thyroid gland or 99mTc-iminodiacetic acid for the examination of hepatobiliary function (i.e. functional efficiency or liver including gall bladder). In the case of bone, this is usually technetium isotope 99mTc. This isotope is deposited in the bone and remains there.
From the bone the particle now emits gamma rays. These gamma rays can be detected with a camera. A color visualized image appears on the computer.
The more frequently the particle emits so-called flashes of light, i.e. gamma rays, the blacker the area in the image appears. In a color image, the color blue stands for a low activity of the radioactive particles in the tissue, while red means that the radioactive particles are very active. Thus, the radioactively marked particles can be used to find out how active the tissue is at the moment.
If areas of the thyroid gland light up blue in a scintigram, you can be sure that this part of the thyroid gland is no longer properly active for some reason. At the same time, the red color indicates a focus of inflammation. If an inflammation occurs in an organ, the metabolism is much more intensive. This leads to increased blood circulation and activity is increased. This can be seen very clearly on the scintigram and thus an accurate diagnosis can be made.