Motivation: Online adaptive radiotherapy with Ethos is based on the anatomy determined from daily cone beam computed tomography (CBCT) images. Dose optimization and computation are performed on the density map of a synthetic CT (sCT), a deformable registration of the initial planning CT (pCT) onto the current CBCT. Large density changes as present in the lung region are challenging the system.
Methods: Treatment plans for Ethos were created and delivered for 1, 2, and 3 cm diameter lung lesions in an anthropomorphic phantom, combining different insets in the pCT and during adaptive and non-adaptive treatment sessions. Primary and secondary dose calculations as well as back-projected dose from portal images were evaluated.
Results: Density changes due to changed insets were not considered in the sCTs. This resulted in errors in the dose; for example, -15.9% of the mean dose for a plan when changing from a 3 cm inset in the pCT to 1 cm at the time of treatment. Secondary dose calculation is based on the sCT and could therefore not reveal these dose errors. However, dose calculation on the CBCT, either as a recalculation in the treatment planning system or as pre-treatment quality assurance (QA) before the treatment, indicated the differences. EPID in-vivo QA also reported discrepancies between calculated and delivered dose distributions.
Conclusions: An incorrect density distribution in the sCT has an impact on the dose calculation accuracy in the adaptive treatment workflow with the Ethos system. Additional quality checks of the sCT can detect such errors.
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http://dx.doi.org/10.1002/acm2.14311 | DOI Listing |
Tech Innov Patient Support Radiat Oncol
March 2025
Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima 770-8503, Japan.
Purpose: This study aims to compare treatment plans created using RapidPlan and PlanIQ for twelve patients with prostate cancer, focusing on dose uniformity, dose reduction to organs at risk (OARs), plan complexity, and dose verification accuracy. The goal is to identify the tool that demonstrates superior performance in achieving uniform target dose distribution and reducing OAR dose, while ensuring accurate dose verification.
Methods: Dose uniformity in the planning target volume, excluding the rectum, and dose reduction in the OARs (the rectum and bladder) were assessed.
Drug Des Devel Ther
January 2025
Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, People's Republic of China.
Purpose: To determine the effect of dexmedetomidine on the ED and ED of sufentanil in patient-controlled intravenous analgesia (PCIA) after cesarean section.
Patients And Methods: Parturients who underwent elective cesarean section (n = 80) were randomly assigned to either the sufentanil group (S group) or the dexmedetomidine-sufentanil combination group (DS group). Patients in the S group received a combination of sufentanil, 5 mg of tropisetron, and saline, whereas patients in the DS group were administered 1.
Anticancer Agents Med Chem
January 2025
Department of Biology, Faculty of Science, Atatürk University, Erzurum, Turkey.
Introduction/objective: Several nutraceuticals, food, and cosmetic products can be developed using royal jelly. It is known for its potential health benefits, including its ability to boost the immune system and reduce inflammation. It is rich in vitamins, minerals, and antioxidants, which can improve general health.
View Article and Find Full Text PDFBMJ Open
December 2024
Clinical Medicine, School of Medicine and Population Health, The University of Sheffield, Sheffield, UK
Introduction: Cortisol is an essential stress hormone and failure of its production, known as adrenal insufficiency (AI), is associated with significant mortality due to adrenal crisis. The Short Synacthen Test (SST) is the current diagnostic test of choice for AI, but it is both invasive and resource intensive. Globally, there is an unmet need for a non-invasive, cost-effective test.
View Article and Find Full Text PDFJ Health Popul Nutr
January 2025
Department of Gastroenterology and Hepatology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, No. 55 Zhenhai Road, Xiamen, 361003, China.
Purpose: Evidence concerning the effect of cardiovascular health (CVH) on the risk of metabolic dysfunctional-associated steatotic liver disease (MASLD) is scarce. This study aimed to investigate the association between CVH and MASLD.
Methods: 5680 adults aged ≥ 20 years from the National Health and Nutrition Examination Survey 2017-March 2020 were included.
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