COMPARISON OF DIGITAL AND ANALOGUE PET/CT: A SYSTEMATIC REVIEW AND META-ANALYSIS

Abstract

Introduction: Digital PET/CT detectors are the latest technology in positron emission tomography, where the analogue photomultiplier tube has been replaced by much smaller silicon photomultipliers. These systems allow single photons to be detected with high sensitivity and low noise. Purpose: The aim of this study was to present digital PET/CT by a systematic literature review, to describe how it compares with analogue systems and to detail the advantages and disadvantages of digital PET/CT scanners.
Methods: Literature was selected according to inclusion and exclusion criteria, focusing only on English-language articles.
Results: The results are presented in two parts. The first part shows the flow of the literature review schematically and the process of how the fi nal number of articles included in the analysis was determined. In the second part, the selected literature was analysed according to the characteristics of the sample, purpose and fi ndings. The literature includes research conducted on phantoms and patients in a clinical setting. The analysis of the articles showed that the digital PET/CT system offers better image quality than analogue PET/CT, the more accurate detection of smaller lesions, in particular, and the possibility of capturing diagnostically useful images while reducing the data acquisition time.
Discussion and conclusion: Most studies focused on exploring the diff erences in the technical capabilities of a digital system
compared to an analogue system. The studies describe the improved image quality of the digital system, which is already
noticeable from a subjective visual assessment. Various analyses have demonstrated improved spatial resolution and signal-to-noise ratio, and improved TOF and SUV. The lesion detection capabilities of digital systems have improved significantly, resulting in greater accuracy in disease staging, prognosis and earlier detection. Studies have shown that digital devices also offer the possibility to reduce the time of data acquisition and the activity of the radiopharmaceutical administered, which is particularly useful in specific clinical circumstances requiring faster examinations.
Keywords: digital PET/CT, analogue PET/CT, radiopharmaceutical,spatial resolution, sensitivity