GAMMA CAMERA

Typical Number in Hospital: 3

Cost Bands: 8

References: 3

This is used in the nuclear medicine or X-ray department for producing a picture of the distribution of radiopharmaceuticals in the body or in particular organs. Individual images can be acquired rapidly into a computer memory, and so it is possible to build up a set of images to show the passage of a particular radiopharmaceutical. The gamma camera is a major advance on the rectilinear scanner since it does not require the head to move to produce a two-dimensional image.

The principal components of a gamma camera are a large sodium iodide crystal coupled to a parallel hole collimator, and a set of photomultiplier (PM) tubes mounted above the crystal. Gamma rays pass through the holes in the collimator and cause flashes of light in the crystal at locations corresponding to their points of origin in the body. The location of the scintillations is calculated by computer from the strengths of light received by the various PM tubes.