Abstract：Objective To evaluate the reliability of positron emission tomography/computed tomography (PET/CT) equipment
inclinical use, to analyze the key parameters affecting the quality control pass rate, and to explore the specific practical methods for
evaluating the reliability of equipment in use. Methods The maintenance records of PET/CT equipment were reviewed and analyzed,
and the parameters related to the availability, maintenance and maintenance of PET/CT equipment were counted. The pass rates of
active quality control LUT drift, energy drift, and TOF drift of PET detectors were calculated and analyzed by Pearson correlation
with environmental factors. Results Both inherent availability (Ainh) and reachable availability (Aa) consistently exceeded 98%, and
the change trend of both was consistent, and Aa was slightly lower. The mean time between failure peak occurred in the fourth year
and exceeded the average level of the three years prior to commissioning. The LUT drift coefficient had a 100% pass rate and was
significantly negatively correlated with system humidity (r=-0.133, P=0.025). The energy drift coefficient had a 78.32% quality
control pass rate, significantly correlated with the outer ring temperature (r=0.162, P=0.006). Therefore, it was advisable for operators
to monitor the temperature and humidity of the machine room closely. Conclusion In the fourth year since commissioning, the
PET/CT equipment has progressed from the initial stage to the normal period stage. During PET detector quality control, it was found
that the energy drift coefficient often goes out of range, which may be related to environmental factors. This study outlines practical
methods for evaluating the reliability of PET/CT equipment in clinical use, offering valuable reference information for improving
reliability and comparing equipment.
