Introduction: PET/CT is a modern diagnostic imaging method where, in addition to anatomical information, the physiological functioning of the patient's body is also observed. Contrast media, metal implants and respiratory motion are the main contributors to PET/CT exclusive artifacts. The elimination of these artifacts or the reduction of their impact is crucial to increase the clinical utility of PET/CT examinations. Purpose: The purpose of the diploma thesis is to present the typical artifacts in PET/CT imaging and to find methods for the reduction of these artifacts and which among them that are the most recommended throughout various literature. Methods: For this diploma work we used a descriptive method and created a literature overview. We were searching for literature on Google Scholar, Pubmed, JNM and COBISS databases. The search of literature lasted from October 2020 to March 2021. Results: We limited the larger number of researches with various factors, so that we came to a number of around 10 studies per each type of PET/CT artifact. Discussion and conclusion: Many studies deal with the issue of PET/CT artifacts. We found that low density contrasts have a relatively small chance of causing artifacts, however artifacts may still occur in some cases. If artifacts occur it is very important that we recognize them as artifacts and not as increased FDG uptake, so that we don’t cause a false positive diagnosis. There are different methods of reducing contrast artifacts, for example the SCC algorithm can be beneficial for decreasing oral contrast artifacts and the global treshhold method is successful for decreasing contrast artifacts in cardio PET/CT. For the elimination of metal artifacts, variants of protocols using the iMAR algorithm have shown to be the most effective. Respiratory gating is the most frequently used method to eliminate respiratory movement artifacts, although data-guided gating proves to be an equally good or even better choice.
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