Pathogenic Yersinia and Listeria monocytogenes in organic pork production

The goal of this study is to determine the prevalence of pathogenic Yersinia and Listeria monocytogenes in organic pork production and assess risks in different steps of the pork production chain

A Respiratory Motion Estimation Method Based on Inertial Measurement Units for Gated Positron Emission Tomography

We present a novel method for estimating respiratory motion using inertial measurement units (IMUs) based on microelectromechanical systems (MEMS) technology. As an application of the method we consider the amplitude gating of positron emission tomography (PET) imaging, and compare the method against a clinically used respiration motion estimation technique. The presented method can be used to detect respiratory cycles and estimate their lengths with state-of-the-art accuracy when compared to other IMU-based methods, and is the first based on commercial MEMS devices, which can estimate quantitatively both the magnitude and the phase of respiratory motion from the abdomen and chest regions. For the considered test group consisting of eight subjects with acute myocardial infarction, our method achieved the absolute breathing rate error per minute of 0.44 +/- 0.23 1/min, and the absolute amplitude error of 0.24 +/- 0.09 cm, when compared to the clinically used respiratory motion estimation technique. The presented method could be used to simplify the logistics related to respiratory motion estimation in PET imaging studies, and also to enable multi-position motion measurements for advanced organ motion estimation.</p

2019 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)

Dynamic Positron Emission Tomography (PET) is a valuable method in Myocardial Perfusion Imaging (MPI) allowing quantification of blood flow in the myocardial tissue. A reference test object simulating myocardial blood flow is needed. A newly developed PET phantom enables flow quantification with a known reference. However, the repetability of the flow phantom needs to be confirmed. The aim of this study was to confirm that no significant variability exists between image-derived or reference flow between subsequent measurements. Finally, we confirmed repeatability of the flow values derived by kinetic modelling from PET images of the phantom. Five repeated measurements with fixed acquisition and reconstruction protocol were performed. PET images were analysed with a software provided by the phantom vendor to derive the time-activity curves for modelling of flow values. The image-derived flow rates varied with SD of 0.89 mL/min and 0.86 mL/min between subsequent measurements. Error between image-derived and reference flow was less than 5.5 % on average within all subsequent repeats. Fluctuations between the subsequent measurements are considered to arise from the dose administration and water flow inside the phantom. In conclusion, the newly developed PET flow phantom shows high repeatability and is a reliable platform for quality control and validation studies in MPI in PET.</p