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Background: Growing evidence suggests that marrow adipocytes play an active role in the regulation of bone metabolism and hematopoiesis. However, research on the relationship between bone and fat in the context of hematological diseases, particularly β‐thalassemia, remains limited. Purpose: To investigate the relationship between marrow fat and cortical bone thickness in β‐thalassemia and to identify key determinants influencing these variables. Study Type: Prospective. Subjects: Thirty‐five subjects in four subject groups of increasing disease severity: 6 healthy control (25.0 ± 5.3 years, 2 male), 4 β‐thalassemia minor, 13 intermedia, and 12 major (29.1 ± 6.4 years, 15 male). Field Strength/Sequence: 3.0 T, 3D fast low angle shot sequence and T1‐weighted turbo spin echo. Assessment: Analyses on proton density fat fraction (PDFF) and R2* values in femur subregions (femoral head, greater trochanter, intertrochanteric, diaphysis, distal) and cortical thickness (CBI) of the subjects' left femur. Clinical data such as age, sex, body mass index (BMI), and disease severity were also included. Statistical Tests: One‐way analysis of variance (ANOVA), mixed ANOVA, Pearson correlation and multiple regression. P‐values <0.05 were considered significant. Results: Bone marrow PDFF significantly varied between the femur subregions, F(2.89,89.63) = 44.185 and disease severity, F(1,3) = 12.357. A significant interaction between subject groups and femur subregions on bone marrow PDFF was observed, F(8.67,89.63) = 3.723. Notably, a moderate positive correlation was observed between PDFF and CBI (r = 0.33–0.45). Multiple regression models for both PDFF (R2 = 0.476, F(13,151) = 10.547) and CBI (R2 = 0.477, F(13,151) = 10.580) were significant. Significant predictors for PDFF were disease severity (βTMi = 0.36, βTMa = 0.17), CBI (β = 0.24), R2* (β = −0.32), and height (β = −0.29) while for CBI, the significant determinants were sex (β = −0.27), BMI (β = 0.55), disease severity (βTMi = 2.15), and PDFF (β = 0.25). Data Conclusion: This study revealed a positive correlation between bone marrow fat fraction and cortical bone thickness in β‐thalassemia with varying disease severity, potentially indicating a complex interplay between bone health and marrow composition. Evidence Level: 2 Technical Efficacy: Stage 3 [ABSTRACT FROM AUTHOR]

Purpose: Monte Carlo (MC) simulation is an important technique that can help design advanced and challenging experimental setups. GATE (Geant4 application for tomographic emission) is a useful simulation toolkit for applications in nuclear medicine. Transarterial radioembolization is a treatment for liver cancer, where microspheres embedded with yttrium‐90 (90Y) are administered intra‐arterially to the tumor. Personalized dosimetry for this treatment may provide higher dosimetry accuracy compared to the conventional partition model (PM) calculation. However, incorporation of three‐dimensional tomographic input data into MC simulation is an intricate process. In this article, 3D Slicer, free and open‐source software, was utilized for the incorporation of patient tomographic images into GATE to demonstrate the feasibility of personalized dosimetry in hepatic radioembolization with 90Y. Methods: In this article, the steps involved in importing, segmenting, and registering tomographic images using 3D Slicer were thoroughly described, before importing them into GATE for MC simulation. The absorbed doses estimated using GATE were then compared with that of PM. SlicerRT, a 3D Slicer extension, was then used to visualize the isodose from the MC simulation. Results: A workflow diagram consisting of all the steps taken in the utilization of 3D Slicer for personalized dosimetry in 90Y radioembolization has been presented in this article. In comparison to the MC simulation, the absorbed doses to the tumor and normal liver were overestimated by PM by 105.55% and 20.23%, respectively, whereas for lungs, the absorbed dose estimated by PM was underestimated by 25.32%. These values were supported by the isodose distribution obtained via SlicerRT, suggesting the presence of beta particles outside the volumes of interest. These findings demonstrate the importance of personalized dosimetry for a more accurate absorbed dose estimation compared to PM. Conclusion: The methodology provided in this study can assist users (especially students or researchers who are new to MC simulation) in navigating intricate steps required in the importation of tomographic data for MC simulation. These steps can also be utilized for other radiation therapy related applications, not necessarily limited to internal dosimetry. [ABSTRACT FROM AUTHOR]

Purpose Accurate and early detection of breast cancer using effective imaging modalities is an active area of research in medical image analysis. Computeraided diagnosis (CAD) of breast cancer using digital mammograms may help in early diagnosis and can assist in maintaining patient health. The breast imaging reporting and data system (BIRADS) is widely used for risk assessment and classification grading in breast cancer screening. It contains seven different grading systems for breast cancer risk assessment. These range from grade 0 (incomplete) to grade 6 (proven malignancy). All other intermediate stages state the progression of risk. Methods: The current research results have shown that two‐dimensional synthesized mammogram (2DSM) imaging and conventional full‐field digital mammography (FFDM) are two important imaging modalities which can be used for screening breast cancer. To the best of our knowledge, there is no study which has yet compared the BIRADS discrimination power of 2DSM and FFDM imaging modalities. In this paper we present a novel CAD‐based comparative study, using texton and gist for the characterization of breast cancer with 2DSM and FFDM imagery. Results: The developed method achieved an average performance of 92.9% accuracy using a probabilistic neural network classifier for FFDM images with tenfold crossvalidation. Hence, our proposed model showed that FFDM images are more effective than the 2DSM imaging modality in discriminating BIRADS grades. Conclusion: The obtained results confirmed that our method performed well in the early detection of breast cancer. Consequently, it can be used as a distinct system in rural hospitals. [ABSTRACT FROM AUTHOR]

Summary: More than half of the world's population live in Asia‐Pacific. This region is culturally diverse, with significant disparities in terms of socio‐economic status, provision of health care and access to advanced technology. The medical use of ionising radiation is increasing worldwide and similarly within the Asia‐Pacific region. In this paper, we highlight the current status in usage of ionising radiation in medicine in the region, and review the legal framework, implementation and activities in radiation protection. Asia‐Pacific countries are active in strengthening radiation protection by promoting education and training. Various projects and activities initiated by international organisations such as the IAEA, WHO and ICRP have provided stimulation in the region, but more work is needed to continue to improve protection practices. [ABSTRACT FROM AUTHOR]

In 2020 the world is facing unprecedented challenges due to COVID‐19. To address these challenges, many digital tools are being explored and developed to contain the spread of the disease. With the lack of availability of vaccines, there is an urgent need to avert resurgence of infections by putting some measures, such as contact tracing, in place. While digital tools, such as phone applications are advantageous, they also pose challenges and have limitations (eg, wireless coverage could be an issue in some cases). On the other hand, wearable devices, when coupled with the Internet of Things (IoT), are expected to influence lifestyle and healthcare directly, and they may be useful for health monitoring during the global pandemic and beyond. In this work, we conduct a literature review of contact tracing methods and applications. Based on the literature review, we found limitations in gathering health data, such as insufficient network coverage. To address these shortcomings, we propose a novel intelligent tool that will be useful for contact tracing and prediction of COVID‐19 clusters. The solution comprises a phone application combined with a wearable device, infused with unique intelligent IoT features (complex data analysis and intelligent data visualization) embedded within the system to aid in COVID‐19 analysis. Contact tracing applications must establish data collection and data interpretation. Intelligent data interpretation can assist epidemiological scientists in anticipating clusters, and can enable them to take necessary action in improving public health management. Our proposed tool could also be used to curb disease incidence in future global health crises. [ABSTRACT FROM AUTHOR]

Aim: Renal biopsy is the gold standard for the histological characterization of chronic kidney disease (CKD), of which renal fibrosis is a dominant component, affecting its stiffness. The aim of this study was to investigate the correlation between kidney stiffness obtained by shear wave elastography (SWE) and renal histological fibrosis. Methods: Shear wave elastography assessments were performed in 75 CKD patients who underwent renal biopsy. The SWE‐derived estimates of the tissue Young's modulus (YM), given as kilopascals (kPa), were measured. YM was correlated to patients' renal histological scores, broadly categorized into glomerular, tubulointerstitial and vascular scores. Results: Young's modulus correlates significantly with tubulointerstitial score (ρ = 0.442, P <.001) and glomerular score (ρ = 0.375, P =.001). Patients with no glomerular sclerosis showed lower mean YM measurements compared to those with glomerular sclerosis. The mean YM increased as the percentage of interstitial fibrosis and tubular atrophy increased. The area under the receiver operating characteristic curve (ROC) for SWE in differentiating between mildly and moderately impaired kidneys was 0.702. Conclusion: Shear wave elastography accurately detects chronic renal damage resulting from glomerular sclerosis, interstitial fibrosis and tubular atrophy, using the optimal cut‐off YM value of ≥5.81 kPa. SUMMARY AT A GLANCE: Shear wave elastography (SWE) is a sonographic technique that may measure tissue stiffness as shear waves propagate faster in harder than in softer tissues. Here the authors share their results of using non‐invasive SWE to examine irreversible damage in chronic kidney disease. [ABSTRACT FROM AUTHOR]

Background: β‐thalassemia is a genetic disease that causes abnormal production of red blood cells (ineffective erythropoiesis, IE). IE is a condition known to change bone marrow composition. Purpose: To evaluate the effect of IE on the marrow fat content and fat unsaturation levels in the proximal femur using 1H‐MRS. Study Type: Prospective. Subjects: Twenty‐three subjects were included in this study, seven control and 16 β‐thalassemia subjects. Field Strength/Sequence: 3.0T; stimulated echo acquisition Mode (STEAM); magnetic resonance spectroscopy (MRS) sequence. Assessment: Multiecho MRS scans were performed in four regions of the proximal left femur of each subject, that is, diaphysis, femoral neck, femoral head, and greater trochanter. The examined regions were grouped into red (diaphysis and femoral neck) and yellow marrow regions (femoral head and greater trochanter). Statistical Tests: The Jonckheere–Terpstra test was used to evaluate the impact of increasing disease severity on bone marrow fat fraction (BMFF), marrow conversion index, and fat unsaturation index (UI). Pairwise comparison analysis was performed when a significant trend (P < 0.05) was found. K‐means clustering analysis was used to examine the clusters observed when BMFF in the red and yellow regions were studied (diaphysis against greater trochanter). Results: BMFF showed a significant decreasing trend with increasing disease severity in both red (TJT = 109.00, z = –4.414, P < 0.05) and yellow marrow regions (TJT = 108.00, z = –4.438, P < 0.05). The opposite trend was observed in UI in both bone marrow regions (red marrow: TJT = 180.5, z = 3.515, P < 0.05; yellow marrow: TJT = 155.0, z = 2.282, P = 0.05). Three distinct forms of marrow adipogenesis were found when plotting BMFF diaphysis against BMFF greater trochanter: 1) normal (centroid: 80.4%, 66.6%), 2) partial disruption (centroid: 51.1%, 16.6%), and 3) total disruption (centroid: 2.6%, 1.6%). Data Conclusion: β‐thalassemia is associated with decreased marrow fat, and increased marrow fat unsaturation level. Level of Evidence: 2 Technical Efficacy Stage: 3 [ABSTRACT FROM AUTHOR]

Oncoplastic breast surgery (OBS) improves margin clearance and produces good esthetic outcome in breast cancer treatment. This study evaluates the complications and outcome of OBS in a multiracial patient cohort. Data of 421 patients between 2011 and 2018 were analyzed. The majority were Malays (41.8%), followed by Chinese (39.7%) and Indians (16.8%). Low local complications were noted, with no significant differences in disease‐free survival (P =.927) and overall survival (P =.719) between low and high OBS levels. Shared decision‐making in offering OBS for Asian women has potential to become a practical option in breast cancer treatment. [ABSTRACT FROM AUTHOR]

Breast density is a strong predictor of the failure of mammography screening to detect breast cancer and is a strong predictor of the risk of developing breast cancer. The many imaging options that are now available for imaging dense breasts show great promise, but there is still the question of determining which women are "dense" and what imaging modality is suitable for individual women. To date, mammographic breast density has been classified according to the Breast Imaging-Reporting and Data System (BI-RADS) categories from visual assessment, but this is known to be very subjective. Despite many research reports, the authors believe there has been a lack of physics-led and evidence-based arguments about what breast density actually is, how it should be measured, and how it should be used. In this paper, the authors attempt to start correcting this situation by reviewing the history of breast density research and the debates generated by the advocacy movement. The authors review the development of breast density estimation from pattern analysis to area-based analysis, and the current automated volumetric breast density (VBD) analysis. This is followed by a discussion on seeking the ground truth of VBD and mapping volumetric methods to BI-RADS density categories. The authors expect great improvement in VBD measurements that will satisfy the needs of radiologists, epidemiologists, surgeons, and physicists. The authors believe that they are now witnessing a paradigm shift toward personalized breast screening, which is going to see many more cancers being detected early, with the use of automated density measurement tools as an important component. [ABSTRACT FROM AUTHOR]