Scanning line source for gamma camera

摘要

A gamma camera system includes two or more radiation detector heads and which are mounted opposite each other to a gantry for rotation about a subject. A transmission radiation source assembly is mounted to the front face of at least one of the detectors and can be moved across the face of the detector. The source assembly includes a radiation attenuating housing, a leaded bronze source holder, and a radionuclide source. The radionuclide source is retained in a longitudinal groove disposed in the source holder. The source holder may be rotated into open, closed, and access positions. The transmission radiation emitted by the source assembly is directed across the examination region, attenuated by the subject, and detected by the opposed detector. The gamma camera system also includes a filter which selectively attenuates the transmission radiation to obtain a desired attenuation profile which prevents saturation of the opposed detector. The filter includes at least one layer of radiation attenuating material of uniform thickness but varying in width in a direction substantially parallel to a direction of motion of the source assembly. An image representation is reconstructed using the radiation emitted by the subject and corrected in accordance with the transmitted radiation data.