Ways of producing images of body organs that record, process and analyse sound waves, radio waves or x-rays passing through or generated by the body’s tissues. Ultrasound scanning using high-frequency, inaudible sound waves directed at the area of the body being studied is the most generally used scanning procedure. Sound waves are reflected more powerfully by some structures than others, and a pattern of those reflections is detected and shown on a screen. Other screening methods include computed tomography, magnetic resonance imaging (MRI), positron emission tomography (pet scanning) and radionuclide scanning, which measures the differential uptake of radioactive materials in the body’s tissues.
Techniques employed to generate images of organ structure, and occasionally function, involve the utilization of sound waves, radio waves, X-rays, or other radiation types directed through bodily tissues.
Ultrasound scanning is a commonly utilized method wherein inaudible, ultra-high-frequency sound waves are transmitted through the body. These sound waves bounce off different bodily structures, generating a pattern that is captured by one or multiple transducers and then visualized on a screen.
CT scanning employs X-rays to assess density variations within an organ. Through computer analysis, this technique constructs an image or visual representation.
Radionuclide scanning, also referred to as scintigraphy, encompasses the introduction of radioactive substances into the body. These substances are absorbed to varying degrees by different organs. For instance, radioactive iodine accumulates in the thyroid gland. A detector is positioned close to the organ under examination, capturing and displaying the emitted radiation pattern on a screen.
MRI (magnetic resonance imaging) employs a robust electromagnet to align hydrogen atoms’ nuclei within the body. Radio waves subsequently disrupt their alignment, causing the nuclei to reorient themselves with the magnetic field. As they realign, these nuclei emit a radio signal that is detectable and converted into a computer-generated image.
PET scanning (positron emission tomography) relies on identifying positively charged particles emitted by radioactively labeled substances administered into the body. A computer is then employed to construct an image representing the chemical activity within the examined tissue.