Noise dependence in PET liver image on patient's applied activity, weight and BMI

The topic of this bachelor thesis is "Dependence of noise in the PET image of the liver on the applied activity, weight and BMI of the patient". Positron emission tomography (PET) is currently one of the most widely used examinations in the field of oncological diseases. The goal of the bachelor thesis is to monitor the noise in the PET image of the liver during positron emission tomography (PET) with FDG (fluorodeoxyglucose) depending on the applied activity, weight and BMI of the patient. Another goal of this work is to propose an alternative algorithm taking into account BMI in order to maintain the image quality and reduce the radiation exposure associated with the examination in addition to the existing algorithm for determining the activity of the applied amount of FDG based purely on patient weight. In connection with these goals, a hypothesis was developed where, taking into account the patient's BMI in determining the activity of the applied amount of FDG, the radiation exposure associated with the examination can be reduced while maintaining the noise level. In the introduction to this bachelor's thesis, I focused on a detailed description of the principle of the PET imaging method, it´s construction and everything associated with the PET imaging method. A substantial part of the theory of this work is occupied by information related to the quality of the PET image, especially the noise level. I also specified the individual radiopharmaceuticals used in the field of PET and I focused more attention on the radiopharmaceutical FDG, which is crucial for this work. Part of this bachelor thesis also deals with the applied activity and the elements related to it, is weight and BMI. In the last part of the bachelor thesis I focused on the description of the hybrid PET / CT method. The practical part was focused on quantitative research. For this research, it was first determined what parameters will need to be found for the processing of the practical part and then data were collected from patients examined by FDG PET / CT at the PET center in the Hospital of České Budějovice a.s. for the calendar year 2021. This data was then graphically plotted and finally used for analysis. In addition to the dependence of noise on patient weight, a representation of weight on patient BMI was created. The results of the practical part showed that the noise is affected by the applied activity, weight and BMI of the patient and based on further analysis, the initial hypothesis was confirmed. The final results of this work can be further used to optimize the examination protocol in the PET center of the Hospital of České Budějovice a.s.