IMAGING THE BODY
|Radio pharmaceuticals used in Nuclear medicine emit gamma
rays that are detected by special types of cameras: gamma or PET
cameras. These cameras work in conjunction with computers used to
project images that provide data and information about the area of the
body being imaged. The amount of radiation from a Nuclear medicine
procedure is comparable to that received during a diagnostic X-ray.
The images produced as a result of small amounts of radiation passing through the body to expose sensitive film on the other side. Whether an X-ray will penetrate tissues and bones depends on the tissue's composition and mass. The image is then created from the differences between those two elements. Contrast agents, such as barium, can be swallowed to highlight the stomach and intestine and can be used to visualize an organ.,
It shows organs of interest as selected. CT examinations produce detailed organ studies by stacking individual image slices. Internal portion of organs and separate overlapping structures can be imaged. The scans are produced when the source of the X-ray beam rotates around the patient. X-rays penetrating through the body are detected by an array of sensors. Information from the sensors is computerized and then displayed as an image on a video screen.
MAGNETIC RESONANCE IMAGING (MRI)
It is a painless technology used to view inside the body without using X-rays. It can produce two as well as three dimensional images using a large magnet, radio waves and a computer. MRI also produces images however it is moreover capable of producing images in an infinite number of projections through the body. A large magnet surrounding the patient is used in conjunction with radio frequencies, and a computer to produce images. The painless magnetic field around the body can be up to 8000 times stronger than that of the earth. The scanner subjects nuclei of the bodies atoms to a radio signal, which will on stopping return to the aligned position, releasing their own faint radio frequencies from which detailed images can be produced and screened on the computer.