ABSTRACT
In hybrid systems, additional CT quality control procedures must be followed. The energy window setting affects uniformity, sensitivity, and scatter contribution to the image. In particular, a large energy window degrades uniformity and sensitivity, whereas increases scattered radiation. A deviation of the sensitivity from the reference value indicates faults in the crystal, in the electrical camera units, or a degradation of the energy resolution. Linearity check is performed half-yearly using the procedure of uniformity determination and a bar phantom that consists of one set of parallel lead bar strips. Among the components of a routine SPECT QC program are the center of rotation alignment, tomographic uniformity and an overall system performance. The developed program is considered as a cost-effective alternative and provides an easy platform for the physicist and technologist to analyze the spatial resolution after the line source image is acquired.
