Master of Science (MS)


Physics and Astronomy

Document Type



The purpose of this research was to evaluate the performance of the imaging characteristics of two versions of a cadmium zinc telluride (CZT) gamma radiation detector system called the Laboratory Radioactive Assay Tracer (LabRAT). The performance evaluation follows the National Electrical Manufacturers Association standards for pixellated detector cameras. The LabRAT detector system hardware was developed by Mosaic Imaging Technology, Inc. LabRAT is a portable nuclear medicine imaging detector system intended for small field of view applications such as small animal imaging, portable radioisotope imaging in emergency room or intensive care units, and as an instruction tool for radiology residents and physics students. The tests performed include the measurement of count rate performance, per-pixel and composite energy resolution, uniformity of detector response, extrinsic spatial resolution, linearity, and integral and differential uniformity. Prior to the performance evaluation acquisition software was developed to operate the detector, including initializing the detector, performing data acquisition and displaying images and energy spectra. One of the systems had a better composite energy resolution due to the fact that the locations of photopeak centers for the individual pixels in that detector were consistently more uniform than the locations for the other detector. The energy resolution attainable for individual pixels is good, but due to limitations in user control over tuning of individual pixels, the composite energy resolution values were higher than expected for both systems. In practice, energy windows must be applied on a per-pixel basis. Spatial uniformity is worse than for typical scintillator-based gamma cameras, while extrinsic spatial resolution is satisfactory.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Kenneth Matthews