Sarcoidosis is a systemic granulomatous disease of unknown etiology that involves many organs, occasionally mimicking malignancy. We herein report a 50-yr-old woman of muscular sarcoidosis of chronic myopathic type, manifested by hypercalcemia and muscle wasting. Besides insignificant hilar lymphadenopathy, her sarcoidosis was confined to generalized atrophic muscles and therefore, F-18 FDG PET/CT alone among conventional imaging studies provided diagnostic clues for the non-parathyroid-related hypercalcemia. On follow-up PET/CT during low-dose steroid treatment, FDG uptake in the muscles disappeared whereas that in the hilar lymph nodes remained. PET/CT may be useful in the evaluation of unexpected disease extent and monitoring treatment response in suspected or known sarcoidosis patients.
Female ; Fluorodeoxyglucose F18/*diagnostic use ; Humans ; Hypercalcemia/complications/*diagnosis ; Kidney Calculi/complications/diagnosis ; Lymph Nodes/radionuclide imaging ; Middle Aged ; Positron-Emission Tomography ; Radiopharmaceuticals/*diagnostic use ; Sarcoidosis/complications/drug therapy/*radionuclide imaging ; Steroids/therapeutic use ; Tomography, X-Ray Computed

The development of MR imaging techniques during the past decade has enabled researchers to use MR imaging as a noninvasive tool for evaluating structural and physiologic states in biologic tissues by measuring the diffusion process of water molecules. More recently, diffusion tensor MR imaging (DTI) technique based on the dependency of molecular diffusion on the orientation of white matter fiber tracts has been used to analyze the trajectory, shape, fiber structure, location, topology and connectivity of neuronal fiber pathways in living humans. Numerous efforts have been made by MR physicists, brain scientists, and medical doctors to advance MR techniques and computer-based algorithms which result in more accurate quantification of diffusion tensor and the generation of white matter fiber tract maps and to determine the pathophysiology of brain disease by DTI and useful clinical applications of DTI. In this article, we describe the tensor theory used to characterize molecular diffusion in white matter and a process of measuring tensor elements using diffusion-sensitive MR images to fiber mapping. We then provide review of current literature and some clinical examples that have been published and are on-going.
Brain Diseases ; Brain* ; Diffusion* ; Humans ; Magnetic Resonance Imaging* ; Neurons

Background: In February 2020, a coronavirus disease 2019 (COVID-19) outbreak was reported in fitness centers in Cheonan, Korea. Methods: From February 24 to March 13, an epidemiological investigation was conducted on the fitness center outbreak. All those who were screened were tested for severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) using real-time reverse transcriptase polymerase chain reaction. Contacts were traced and self-isolated for 14 days. We determined the epidemiological characteristics of confirmed cases of SARS-CoV-2 infection, and estimated the time-dependent reproduction number to assess the transmission dynamics of the infection. Results: A total of 116 cases were confirmed, and 1,687 contacts were traced. The source cases were 8 Zumba instructors who led aerobics classes in 10 fitness centers, and had the largest average number of contacts. A total of 57 Zumba class participants, 37 of their family members, and 14 other contacts were confirmed as cases. The attack rate was 7.3%. The contacts at Zumba classes and homes had a higher attack rate than other contacts. The mean serial interval (± standard deviation) were estimated to be 5.2 (± 3.8) days. The time-dependent reproduction number was estimated to be 6.1 at the beginning of the outbreak, but it dropped to less than 1, 2 days after the epidemiological investigation was launched. Conclusion The results suggest that the COVID-19 outbreak was effectively contained with rigorous contact tracing, isolating, and testing in combination with social distancing without a lock-down.