[Changes in FDG-PET Images of Small Lung and Liver Masses Caused by the Deep Learning-based Time-of-flight Processing].

Purpose: The deep learning time-of-flight (DL-ToF) aims to replicate the ToF effects through post-processing, applying deep learning-based enhancement to PET images. This study evaluates the effectiveness of DL-ToF using a chest-abdomen phantom that simulates human anatomical structures.

Methods: The 3 DL-ToF intensities (Low-DL-ToF: LDL, Middle-DL-ToF: MDL, High-DL-ToF: HDL) were adopted for the PET image of the chest-abdomen phantom.

Detectability of category 3 or higher microcalcifications on digital mammograms: a comparative study between 5-MP color and monochrome liquid crystal display monitors.

This study explored the detectability of category 3 or higher microcalcifications using 5-MP color and monochrome monitors. Contrast detail mammography phantom with polymethyl methacrylate (PMMA) images were observed in color and monochrome by five radiographers, and the image quality figures (IQF) were calculated based on the gold disc locations identified. Five radiographers and two radiologists observed 200 mammograms from 100 patients (including 36 with microcalcifications) and rated the microcalcifications.

Continuous bed motion in a silicon photomultiplier-based scanner provides equivalent spatial resolution and image quality in whole body PET images at similar acquisition times using the step-and-shoot method.

This study investigated the spatial resolution and image quality of the continuous bed motion (CBM) method in a sensitive silicon photomultiplier (SiPM)-based positron emission tomography (PET)/computed tomography (CT) system compared with the traditional step-and-shoot (SS) method. Siemens Biograph Vision was used in this study. Data acquisition using the SS method was performed for 3 min per bed.

Evaluating and comparing the image quality and quantification accuracy of SiPM-PET/CT and PMT-PET/CT.

Objective: The aim of this study was to evaluate the image quality and the quantification accuracy of Biograph Vision PET/CT scanner as a SiPM-PET in comparison to the conventional PMT-PET, Biograph mCT PET/CT scanner.

Methods: This study consisted of a phantom study and a retrospective clinical analysis where patients underwent F-FDG PET/CT in both PET systems. The body phantom of the NEMA IEC with 10-37 mm diameter spheres were filled with an F-FDG solution.

[Evaluation of the Number of Sampling Angles in Three Dimensional Ordered Subset Expectation Maximization: Comparison of Step and Shoot Acquisition and Continuous Acquisition].

Three dimensional ordered subset expectation maximization (3D-OSEM) improves spatial resolution and contrast. Continuous acquisition, and step and shoot acquisition are used in single photon emission computed tomography (SPECT). The purpose of this study was to evaluate the effect of 3D-OSEM when acquisition method was different.

Characteristics of Smoothing Filters to Achieve the Guideline Recommended Positron Emission Tomography Image without Harmonization.

Objectives: The aim of this study is to examine the effect of different smoothing filters on the image quality and SUV to achieve the guideline recommended positron emission tomography (PET) image without harmonization.

Methods: We used a Biograph mCT PET scanner. A National Electrical Manufacturers Association (NEMA) the International Electrotechnical Commission (IEC) body phantom was filled with F solution with a background activity of 2.

Edge Artifacts in Point Spread Function-based PET Reconstruction in Relation to Object Size and Reconstruction Parameters.

Objectives: We evaluated edge artifacts in relation to phantom diameter and reconstruction parameters in point spread function (PSF)-based positron emission tomography (PET) image reconstruction.

Methods: PET data were acquired from an original cone-shaped phantom filled with F solution (21.9 kBq/mL) for 10 min using a Biograph mCT scanner.

Estimation of ambient dose equivalent distribution in the F-FDG administration room using Monte Carlo simulation.

In this study, we estimated the ambient dose equivalent rate (hereafter "dose rate") in the fluoro-2-deoxy-D-glucose (FDG) administration room in our hospital using Monte Carlo simulations, and examined the appropriate medical-personnel locations and a shielding method to reduce the dose rate during FDG injection using a lead glass shield. The line source was assumed to be the FDG feed tube and the patient a cube source. The dose rate distribution was calculated with a composite source that combines the line and cube sources.

Reduction of the unnecessary dose from the over-range area with a spiral dynamic z-collimator: comparison of beam pitch and detector coverage with 128-detector row CT.

Our purpose in this study was to assess the radiation dose reduction and the actual exposed scan length of over-range areas using a spiral dynamic z-collimator at different beam pitches and detector coverage. Using glass rod dosimeters, we measured the unilateral over-range scan dose between the beginning of the planned scan range and the beginning of the actual exposed scan range. Scanning was performed at detector coverage of 80.