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The annual meeting of the Radiological Society of North America was held from Dec. 1 to 5 in Chicago, drawing participants from around the world, including radiologists, radiation oncologists, physicists in medicine, radiologic technologists, and other health care professionals. The conference featured scientific papers from a number of subspecialties covering the newest trends in radiological research, as well as education and informatics exhibits. In an observational study, Elena Ghotbi, M.D., of the Johns Hopkins University School of Medicine in Baltimore, and colleagues identified an association between bone loss and levothyroxine, the second most commonly prescribed medication among older adults in the United States. The association did not include an increased prevalence of clinically significant low bone density, such as rates of osteoporosis. The authors aimed to determine if levothyroxine use and higher thyroid hormone levels within the reference range were associated with higher bone loss with normal thyroid function. Data from the prospective, observational, Baltimore Longitudinal Study of Aging were evaluated. During a median follow-up of 6.3 years, the researchers found that levothyroxine use was associated with greater loss of total body bone mass and bone density, even in participants with thyroid-stimulating hormone (TSH) levels within the normal range and when accounting for baseline TSH and other risk factors. Data also indicated that levothyroxine may be prescribed in some older adults when it is not truly indicated. However, to establish causality and clarify the potential long-term musculoskeletal risks of levothyroxine use in this population, further research, including randomized trials, is necessary, according to the authors. "While it is too early to draw clinical conclusions based on these preliminary observational findings, the study raises important questions. For instance, thyroid hormone is sometimes initiated in patients who do not have hypothyroidism, such as for managing symptoms despite normal hormone levels," Ghotbi said. "Patients with concerns should consider discussing their diagnosis and treatment goals with their health care provider to ensure the appropriateness of their therapy." Press Release In another study, Kevin C. Yu, of the Wake Forest University School of Medicine in Winston-Salem, North Carolina, and colleagues found that concussions are related to reduced cortical excitability in the frontal cortex, which is associated with worse cognitive function. The authors collected preseason and postseason resting-state magnetoencephalography data to identify the impacts of concussions on aperiodic activity. The Post-Concussive Symptom Inventory, a clinical evaluation tool for concussions, was used to correlate preseason and postseason physical, cognitive, and behavioral symptoms. The researchers found that concussion reduces cortical excitability in parts of the brain important for cognitive function, like attention. These concussion-related changes in cortical excitability were also associated with worse cognitive symptoms. "We believe these findings are important, both because they provide insight into the mechanisms and clinical implications of concussion in the adolescent brain, and because they may inform recommendations for clinical monitoring and intervention strategies for individuals with head trauma," Yu said. "This study highlights the importance of monitoring the brain signaling of adolescents carefully after any head injury and taking concussion seriously. It also underscores the importance of protective measures in sports and ensuring that young adults take the necessary time to fully recover before returning to play." Press Release Mahsa Dolatshahi, M.D., of the Mallinckrodt Institute of Radiology at the Washington University School of Medicine in St. Louis, and colleagues found that visceral adipose tissue, or deep belly fat -- but not other types of fat -- plays a role in the hallmark pathologies of Alzheimer disease. The authors evaluated 80 cognitively normal middle-aged individuals who underwent brain positron emission tomography, body magnetic resonance imaging (MRI), metabolic assessment, and blood lipid level evaluation. The researchers found that visceral adiposity mediated the link between high body mass index (BMI) and amyloid deposition in the brain, and is likely linked to early tau pathology, independent of BMI. While high BMI, as the classic definition of obesity, is important, it is not the whole story, as other types of fat or muscle mass are not particularly linked to these pathologies, the authors note. They stress that modification of visceral adiposity, coupled with dyslipidemia, should be the focus of interventions for brain health-related outcomes. The effect of visceral fat on amyloid accumulation is partly mediated by lower high-density lipoprotein. "The impacts on clinical practice for now are mostly limited to suggestions at preventive levels for modifying excess body fat," Dolatshahi said. "We need more longitudinal and interventional studies to understand the effects of different lifestyle and social determinants in visceral adiposity and brain health." Press Release Marianne Nabbout, M.D., of the University of Arkansas for Medical Sciences in Little Rock, and colleagues found that one episode of electronic cigarette inhalation can have an acute and measurable effect on vascular beds. The researchers aimed to demonstrate the acute effects of tobacco smoking and nicotinized and nonnicotinized e-cigarette vaping on vascular function among healthy smokers and vapers using quantitative MRI. Study participants underwent two MRI exams, one before and one after each of the following smoking/vaping episodes: tobacco cigarette, e-cigarette aerosol with nicotine, and e-cigarette aerosol without nicotine. Following nicotinized and nonnicotinized e-cigarette vaping challenges, baseline venous oxygen saturation significantly decreased in the superficial femoral vein, which suggests an immediate decrease in the uptake of oxygen by the lungs following e-cigarette smoking. In the superficial femoral artery, the time of forward flow (the duration of monophasic waveform during reactive hyperemia that occurs due to decreased microvascular resistance) was significantly decreased following both nicotinized and nonnicotinized e-cigarette vaping challenges. Following inhalation of each type of vaping or smoking, there was a significant decrease seen in the resting blood flow velocity in the superficial femoral artery. The hyperemic index (at the superficial femoral artery) was significantly decreased following nicotinized e-cigarette vaping. "These observations may suggest depressed hyperemia in the femoral artery following induced ischemia via cuff occlusion at the level of the upper thigh," Nabbout said. "The reason we saw significant effects following nonnicotinized electronic cigarette vaping may be due to the presence of harmful constituents other than nicotine. The study is ongoing to acquire more data. The larger the sample size, the more likely we are to detect statistically significant effects." Press Release Keegan Staab, of the University of Iowa in Iowa City, and colleagues identified a link between lung function and brain function in patients with long COVID that could lead to a better understanding of the mechanisms responsible for the persistent dyspnea and cognitive symptoms observed after COVID-19 infection. The researchers aimed to gain insight into the link between pulmonary MRI gas exchange, structural and functional brain MRI, and cognition among patients with long COVID. They found that pulmonary gas exchange measured using hyperpolarized xenon MRI was related to cognitive function assessed using the National Institutes of Health Toolbox and brain perfusion measured via MRI. "Previous work has attributed perceived cognitive deficits to psychological distress rather than an underlying disease process," Staab said. "Our data provide evidence that this may not be the case and could be caused by underlying physiological and persistent lung abnormalities." Press Release RSNA: Opportunistic Assessment of Aortic Calcium Predicts MACE MONDAY, Dec. 9, 2024 -- A fully automated algorithm to quantify aortic artery calcification on computed tomography scans performed for other clinical purposes can predict the risk for subsequent major adverse cardiovascular events, according to a study presented at the annual meeting of the Radiological Society of North America, held from Dec. 1 to 5 in Chicago. Read Full Text RSNA: Genicular Artery Embolization Effective, Safe for Knee Osteoarthritis FRIDAY, Dec. 6, 2024 -- Genicular artery embolization is effective and safe for reducing osteoarthritis symptoms among patients with knee osteoarthritis that is refractory to conservative therapy, according to a study presented at the annual meeting of the Radiological Society of North America, held from Dec. 1 to 5 in Chicago. Read Full Text RSNA: Obesity, VAT Linked to Measures of Amyloid Burden in Midlife WEDNESDAY, Dec. 4, 2024 -- Obesity and visceral fat are associated with measures of amyloid burden in the brain among cognitively normal midlife individuals, according to a study presented at the annual meeting of the Radiological Society of North America, held from Dec. 1 to 5 in Chicago. Read Full Text RSNA: Silicosis Often Missed in Engineered Stone Countertop Workers TUESDAY, Dec. 3, 2024 -- Few primary clinicians or radiologists recognize silicosis among engineered stone countertop workers, according to a study presented at the annual meeting of the Radiological Society of North America, held from Dec. 1 to 5 in Chicago. Read Full Text RSNA: Levothyroxine Tied to Bone Loss Over Time in Older Adults MONDAY, Nov. 25, 2024 -- Levothyroxine use is associated with longitudinal loss of bone mass and density in older adults, according to a study scheduled to be presented at the annual meeting of the Radiological Society of North America, held from Dec. 1 to 5 in Chicago. Read Full Text Whatever your topic of interest, subscribe to our newsletters to get the best of Drugs.com in your inbox.