Search

Brain metastases are frequent complications for lung cancer patients. However, changes in the brain of lung cancer patients have received little attention. We aimed to explore whether alterations in brain glucose uptake and brain texture occur in non‐small cell lung cancer (NSCLC) patients and to investigate associations between brain alterations and NSCLC via the uEXPLORER positron emission tomography/computed tomography (PET/CT) system. In total, 105 participants were enrolled, including 55 healthy controls and 50 NSCLC patients. Images were acquired using the PET/CT system. Standardized uptake values normalized by lean body mass were calculated as indicators of glucose uptake. Correlation analysis was conducted between aberrant brain glucose uptake, glucose uptake of cancer lesions, and concentrations of serum lung cancer markers. Radiomics was used to investigate whether features extracted from regions with altered brain glucose uptake could serve as biomarkers of lung cancer progression. Compared with healthy controls, NSCLC patients showed decreased standardized uptake values normalized by lean body mass in the left insula, medial frontal gyrus, and anterior cingulate. Correlation analysis demonstrated that glucose uptake of the anterior cingulate was negatively correlated with serum lung cancer marker concentrations. Radiomic features on PET/CT images of the above brain regions could classify NSCLC patients and healthy controls with an accuracy of 79%. NSCLC patients exhibited altered brain glucose uptake and changes in brain textures. These alterations may reflect alterations in behavioral domains in NSCLC and may be related to altered lung‐brain interactions and potential brain metastasis of NSCLC. Non‐small cell lung cancer patients exhibited altered brain glucose uptake in several regions. The aberrant brain glucose uptake may be related to lung‐brain interactions or brain metastases. Machine learning identified several biomarkers for brain metastasis and lung‐brain interactions.

Purpose: Computer-based simulation offers radiological students the possibility to experiment with computed tomography in a way not possible in class or in clinical practice. The aim of this study was to design a computed tomography numerical simulator (CTSim) for high-quality radiological education. Methods: In this study, a CTSim is designed based on the mathematical and physical principles of CT imaging. The proposed CTSim includes pen-beam module, fan-beam module, and clinical CT module. The core design of the software includes four parts: the construction of sample models, construction of imaging parameters and artifact parameters, design of data acquisition models under different scanning modes, and design of image reconstruction algorithm. After the design of the CTSim, the proposed CTSim was tested in every step of CT imaging. Results: Systematic verification demonstrated that the proposed CTSim can not only perform raw CT data acquisition, image reconstruction, basic image processing, and image quality analysis like a real CT scanner, but can also simulate the formation of artifacts. The CTSim can completely get rid of the hardware and achieve the same experimental results as the hardware instrument. Conclusion: The proposed CTSim software shows several advantages such as low cost, less room accommodation, and no ionizing radiation damage and can be used as a virtual experimental training platform to enhance teaching and learning for general X-ray CT courses or for self-study of CT practitioners.

A growing number of studies have demonstrated that the skeleton is an endocrine organ that is involved in glucose metabolism and plays a significant role in human glucose homeostasis. However, there is still a limited understanding of the in vivo glucose uptake and distribution across the human skeleton. To address this issue, we aimed to elucidate the detailed profile of glucose uptake across the skeleton using a total-body positron emission tomography (PET) scanner. A total of 41 healthy participants were recruited. Two of them received a 1-hour dynamic total-body 18F-fluorodeoxyglucose (18F-FDG) PET scan, and all of them received a 10-minute static total-body 18F-FDG PET scan. The net influx rate (Ki) and standardized uptake value normalized by lean body mass (SUL) were calculated as indicators of glucose uptake from the dynamic and static PET data, respectively. The results showed that the vertebrae, hip bone and skull had relatively high Kiand SUL values compared with metabolic organs such as the liver. Both the Kiand SUL were higher in the epiphyseal, metaphyseal and cortical regions of long bones. Moreover, trends associated with age and overweight with glucose uptake (SULmaxand SULmean) in bones were uncovered. Overall, these results indicate that the skeleton is a site with significant glucose uptake, and skeletal glucose uptake can be affected by age and dysregulated metabolism.

A prototype PET camera has been designed and is being constructed to test the concept, and develop the engineering design and production methodology for a variable field PET camera. The long term goal of the design is to develop a lower cost, high resolution PET camera. The camera has eight detector heads which form a closely packed octagon detector ring with an average diameter of 44 cm for brain/breast and animal model imaging. The heads can be translated radially to a maximum ring diameter of 70 cm for whole body imaging. In the larger diameter modes, the camera rotates 45/spl deg/ during imaging. The camera heads can be set to intermediate positions to fit the camera to the subject size to maximize detection sensitivity and sampling uniformity. Special design features for imaging the breast and the axillary metastases have been incorporated. The detector design implemented is the quadrant sharing photomultiplier (PMT) design using circular 19 mm PMT. The BGO detector pitch size is 2.7/spl times/2.7 mm. The prototype camera images 27 slices simultaneously with an axial field of view (FOV) of 39 mm. The prototype's limited axial FOV, which is appropriate for testing the camera concept, would be expanded in a next-generation clinical camera implementation. Preliminary simulation studies have been performed to evaluate the resolution, sensitivity, and sampling uniformity.