Gamma Camera

INTRODUCTION:- GAMMA CAMERA:- An electronic instrument used in medical diagnostics to image the distribution of radioactive compounds in animal tissue. A gamma camera is a medical imaging device used in nuclear medicine. It produces images of the distribution of gamma ray emitting radio nuclides.

In the begining The early type of device used to create images of radioactivity distributions within the body, was the rectilinear scanner. This device dominated nuclear medicine in the 1950s and 1960s The rectilinear scanner used one or two large detectors, which scanned the patient in a rectilinear fashion. Scanning was slow and the images were poor to say the least.

The Gamma camera:- One of the limitations of the rectilinear scanner was the necessity to acquire information point by point. In the late 1950s a device was invented by Hal O Anger in California, which could image many points simultaneously. This device began to replace the rectilinear scanner in the 1960s, and became known as: The Gamma Camera. The Scintillation Camera. The Anger Camera.

Hal Anger 1920-2005

The Gamma Camera The detector contains a disk or rectangular shaped crystal of NaI(Tl), typically 3/8” thick, coupled to an array of 37 or 61 or 91 photomultiplier tubes. The crystal is usually connected to the PMTs by a Lucite light pipe and optical grease, which helps the distribution of light emanating from the crystal.

Some designs however have the PMTs bonded directly to the glass window of the crystal.