Individualized adjustments to reference phantom internal organ dosimetry - scaling factors given knowledge of patient external anatomy.

This study aims to better personalize internal radiation dose estimates for individual patients by modifying the dose estimates calculated for reference individuals based on easily obtainable morphometric characteristics of the patient. Phantoms of different sitting heights and waist circumferences were constructed based on computational reference phantoms for the newborn, 10-year-old, and adult. Monoenergetic photons and electrons were then simulated separately at 15 energies. Photon and electron specific absorbed fractions (SAFs) were computed for the newly constructed non-reference phantoms and compared to SAFs previously generated for the age-matched reference phantoms. Differences in SAFs were correlated to changes in sitting height and waist circumference to develop scaling factors that could be applied to reference SAFs as morphometry corrections. A further set of arbitrary non-reference phantoms were then constructed and used in validation studies for the SAF scaling factors. Both photon and electron dose scaling methods were found to increase average accuracy when sitting height was used as the scaling parameter (~11%). Photon waist circumference-based scaling factors showed modest increases in average accuracy (~7%) for underweight individuals, but not for overweight individuals. Electron waist circumference-based scaling factors did not show increases in average accuracy. When sitting height and waist circumference scaling factors were combined, modest average gain...
Source: Physics in Medicine and Biology - Category: Physics Authors: Tags: Phys Med Biol Source Type: research

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The objective of this study was to determine the impact of obesity on quality of life as measured by the BREAST-Q, in women undergoing breast reconstruction. Methods A review of the breast reconstruction database (n = 336) at the Flinders Breast Reconstruction Service was performed, with demographic data, complication rates, and BREAST-Q data being extracted and analyzed. Participants were divided into 2 groups: nonobese (BMI
Source: Annals of Plastic Surgery - Category: Cosmetic Surgery Tags: Breast Surgery Source Type: research
Objective We aimed to compare the demographic, laboratory, and ambulatory blood pressure monitoring (ABPM) parameters of patients with masked hypertension (MHT), define factors predicting MHT, and determine the ABPM parameters affecting left ventricular mass index (LVMI) in obese youth. Methods Data of obese patients were evaluated retrospectively. Patients with ambulatory hypertension (AHT), white-coat hypertension (WCHT), MHT, or normotension (NT) were determined. Demographic and laboratory findings, office and ABPM measurements, blood pressure variability (BPV), and heart rate variability (HRV) were compared betwee...
Source: Blood Pressure Monitoring - Category: Cardiology Tags: Clinical Methods and Pathophysiology Source Type: research
Background: Obesity is closely related to many chronic diseases and metabolic risk factors. The present study examined the relationship of obesity-related indices to blood pressure (BP) and fasting plasma glucose (FPG) among young Chinese men. Methods: A total of 1193 male college students aged 18–22 years participated in the study. Height, weight, waist circumference (WC), body mass index (BMI), waist-to-height ratio (WHtR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and FPG were measured. High BP was defined as SBP ≥140 mmHg and/or DBP ≥90 mmHg. Impaired fasting glucose (IFG) was defin...
Source: Blood Pressure Monitoring - Category: Cardiology Tags: Clinical Methods and Pathophysiology Source Type: research
Publication date: Available online 11 November 2019Source: The Journal of Allergy and Clinical Immunology: In PracticeAuthor(s): Marcello Cottini, Anita Licini, Carlo Lombardi, Alvise BertiAbstractBackgroundThe involvement of small airways has recently gained greater recognition in asthma. Impulse oscillometry (IOS) is a simple and noninvasive method based on the forced oscillation technique, for the detection of small airway dysfunction (SAD).ObjectiveWe aimed to identify the predictors of SAD in an unselected sample of 400 patients with physician-diagnosed asthma.MethodsAll patients underwent standard spirometry and IOS ...
Source: The Journal of Allergy and Clinical Immunology: In Practice - Category: Allergy & Immunology Source Type: research
Publication date: Available online 11 November 2019Source: Journal of Chemical NeuroanatomyAuthor(s): Pedro Augusto Silva Nogueira, Miriam Pimenta Pereira, Jeferson José Gomes Soares, Juliana de Assis Silva Gomes, Daniele Lisboa Ribeiro, Daniela Soares Razolli, Licio Augusto Velloso, Morun Bernardino Neto, Renata Graciele ZanonAbstractThe arcuate and the paraventricular and lateral hypothalamic nuclei, related to hunger and satiety control, are generally compromised by excess fatty acids. In this situation, fatty acids cause inflammation via TLR4 (toll like receptor 4) and the nuclei become less responsive to the ho...
Source: Journal of Chemical Neuroanatomy - Category: Neuroscience Source Type: research
Publication date: Available online 12 November 2019Source: Food BioscienceAuthor(s): Zhihui Yu, Ning Wang, Fang Geng, Meihu MaAbstractObesity induced by consuming a high-fat diet (HFD) is a major risk for nonalcoholic fatty liver disease, which has become a worldwide health problem. To study the effects of high-density lipoproteins of egg yolk (EYHDL) on mice with HFD induced obesity, lipidomic analyses using ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was done with serum and liver samples on 60 and 100 days. The results showed that EYHDL significantly alleviated mouse obesity by decreasin...
Source: Food Bioscience - Category: Food Science Source Type: research
New study suggests that a'threshold'of weight loss must be reached after bariatric surgery to see a reduced risk of obesity-related cancer. Another indicates risk may be reduced by around 20%.Medscape Medical News
Source: Medscape Hematology-Oncology Headlines - Category: Cancer & Oncology Tags: Diabetes & Endocrinology News Source Type: news
Publication date: Available online 11 November 2019Source: Fuß &SprunggelenkAuthor(s): N. Maffulli, R. AicaleAbstractIn the past three decades, the incidence of overuse tendinopathy has risen. Tendinopathy affects also middle-aged overweight patients with no history of increased physical activity. Tendinopathy is the result of a chronic failure of healing response. Several conservative therapeutic options have been proposed.The management of tendinopathy is primarily conservative, and many patients respond to such measures. Eccentric exercises and shock wave therapy provide promising excellent clinical results. H...
Source: Fuss and Sprunggelenk - Category: Podiatry Source Type: research
Conclusions: Over the past decade, eligible patients are experiencing longer wait times when pursuing bariatric surgery. Complex patients with Medicaid insurance are experiencing the longest delay despite similar outcomes and preoperative weight loss. Policies that delay surgery should be re-examined.
Source: Annals of Surgery - Category: Surgery Tags: ORIGINAL ARTICLES Source Type: research
Conclusions: Patients with diverticulitis have high surgical site infection rates due to nonmodifiable risk factors. Our Prediction and Enaction of Prevention Treatments Trigger scale can risk stratify patients for targeting surgical site infection prevention bundles and outcomes risk adjustments.
Source: Annals of Surgery - Category: Surgery Tags: ORIGINAL ARTICLES Source Type: research
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