Scintigraphy and Gamma Camera

Scintigraphy and Gamma Camera used in veterinary medicine for diagnostic purpose. these described below.

Scintigraphy

Scintigraphy is a branch of nuclear medicine. It is an imaging technique in which radionuclides (radioactive elements emitting gamma rays) are administered to a subject.

The radionuclides are attached to chemicals to form radiopharmaceuticals that accumulate in the tissue of interest. Most radiopharmaceuticals are analogues of physiologic substances or biologic organic molecules. Their presence, and their concentration, can be detected by gamma-ray detection equipment—usually a gamma ray camera.

The gamma rays are converted by the camera into signals from which a computer produces a digital format that is used to construct an image of the area under examination. Nuclear medicine images are described in terms of uptake of the radiopharmaceutical.

The degree of uptake is subjectively assessed in some techniques, while in others quantitative analysis is performed. In this way normal and abnormal tissues can be identified by the selective accumulation of the radioactive substances within them.

Gamma Camera

The gamma camera is an imaging technique used to carry out functional scans of the brain, thyroid, lungs, liver, gallbladder, kidneys and skeleton of animals.

Gamma cameras image the radiation from a tracer introduced into the patient’s body. The most commonly used tracer is technetium-99m, a metastable nuclear isomer chosen for its relatively long half-life of six hours and its ability to be incorporated into a variety of molecules in order to target different systems within the body. As it travels through the body and emits radiation the tracer’s progress is tracked by a crystal that scintillates in response to gamma-rays. 

The crystal is mounted in front of an array of light sensors that convert the resulting flash of light into an electrical signal. Gamma cameras differ from X-ray imaging techniques in one very important respect; rather than anatomy and structure, gamma cameras map the function and processes of the body.