The purpose of the study is to evaluate the physical performance of a Biograph mCT Flow R PET/CT system (Siemens Healthcare, Germany) and to. to fundamentally change how PET imaging is performed. Powered by Siemens’ revolutionary FlowMotion™ technology,. Biograph mCT Flow™ is the world’s first. Biograph mCT Flow with FlowMotion™ technology combines our standard- setting PET/CT with a unique system design that enables continuous motion of.
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The NEMA performance parameters obtained for the mCT Flow system are in concordance with the published bioyraph for the predecessor system. Online random subtraction was applied from the delayed coincidence window to account also for the intrinsic LSO radioactivity [ 23 ].
The CTM FlowMotion technology requires a new design of the patient table and the acquisition electronics.
All procedures performed in studies involving human participants were approved by the regional ethics committee and were in accordance with the Helsinki declaration. No attenuation and scatter correction and no post-smoothing filter were applied. For the OSEM reconstruction, the results were slightly worse, which can be explained by the difference in applied post-filtering 3-mm FWHM vs 5-mm FWHM and the difference in iterations and subsets; the larger buograph of subsets in our study will lead to an enhancement of the noise in the image.
The CRCs were similar in both acquisition modes. Furthermore, the axial placement of the off-center axial point sources was changed from one fourth of the axial FOV from the center to three eighth of the axial FOV from the center, respectively. Random sinogram variance reduction in continuous bed motion acquisition.
The calculated activities at the start of the second scan were 5. Data were acquired at three transaxial locations xy: Accuracy of count losses and random corrections For this evaluation, the measurements acquired for the evaluation of the scatter fraction and count rate performance was used.
Based on the results of Armstrong [ 25 ], this difference would increase for the smaller spheres when TOF was included into the reconstruction algorithm. Methods for improving image quality in whole body PET scanning. For an axial FOV excluding the low sensitivity regions at the axial endpoints of the scan range a hypothetical scan with an unlimited number of bed positionsa biograpn acquisition per bed position corresponds to a table speed of 0.
The system sensitivity was then computed as the ratio between the true count rate with no absorption and the starting activity. Sensitivity measurements were based on a cm-long polyethylene tube, filled with 4.
Biograph mCT for Radiation Oncology – Siemens Healthineers Global
Mean standardized uptake bigraph SUVs mean biograoh coefficient of variations CVs were calculated for spherical volumes of interest VOI with 3-cm diameter placed in the liver and the bladder. Nevertheless, based on the findings of Molina-Duran and colleges, [ 33 ] not the entire increase in BG variability can be explained from the decrease in count density. The bladder was chosen to test for this issue as it contains a uniform activity concentration and therefore similar to the background compartment in the IQ phantom.
Image quality is very similar. The changes in bladder filling are caused by the time between the scans. Our data indicate a similar performance of the PET components of the mCT Flow and its predecessor system, the mCT [ 6 ] with the residual differences being discussed below.
The line source for the scatter phantom was filled with a solution of 18 F-FDG and water. The maximum and minimum errors for all activity concentrations are depicted in Fig. Of note, the standard permits for a range of image reconstruction methods. We thank Alexander Haug Vienna for helping with the clinical comparison of the images. The reconstructions of the transaxial sections through the center of the spheres within the image quality phantom for SS and CTM mode are shown in Fig.
Ethical approval All procedures performed in studies biogrpah human participants were approved by the regional ethics committee and were in accordance with the Helsinki declaration. The contrast values, background mcr, and the accuracy of attenuation and scatter correction for the lung insert were evaluated with an in-house developed plug-in for ImageJ U. Within the SS protocol, the table is in a fixed position during an acquisition of data in the FOV and subsequently moves to the next position to acquire data of an axial range greater than the axial FOV of the system.
Time of flight in PET revisited.
Biograph mCT 20 Excel – Siemens Healthineers Global
The extra bed position information is then employed during the data processing, thus, assuring that the final reconstructed images contain the correct position information. The evaluation of positron emission tomographs requires reproducible and reliable methods to allow the comparison of bbiograph systems using accepted measurement standards. The axial sensitivity profiles with the line source placed at the center of the FOV and cm radial offset are shown in Fig. These settings were selected to cover the same axial FOV in the same time as performed with the IQ phantom measurements.
The measured sensitivity was 9. Evaluation was done using in-house software.
Biograph mCT Flow
The count rate error evaluation was also slightly modified in the standard. All measurements were performed at the site of the clinical installation of the system between August and December System true event rate, random event rate, scatter event rate, NECR, and the scatter fraction are reported.
In a study by Tong et al. These artifacts can be reduced by applying post-filtering with small to modest amounts of blurring but at the cost of lower image contrast.