The purpose of this investigation was to compare the commercial 3D-treatment planning system Helax TMS to a simple 2D program ASYMM, concerning the calculation of dose distributions for asymmetric fields. The dose calculation algorithm in Helax-TMS is based on the polyenergetic pencil beam model of Ahnesjö. Our own developed 2D treatment planning program ASYMM, based on the Thomas and Thomas method for asymmetric open fields, has been extended to calculate the dose distributions for open and wedged fields. Using both methods, dose distributions for various asymmetric open and wedged fields of a 4-MV Linear accelerator were calculated and compared with measured data in water. The agreement of the Helax-TMS and the ASYMM with the experiment was good, whereas ASYMM showed a better accuracy for larger asymmetric angles. The explanation for this result is based on the consideration of beam hardening within the flattening filter and edges for different asymmetric settings in ASYMM algorithm. The TMS, however, owns the diverse possibilities that the 3D calculation and corresponding representation provide and holds better application opportunities in clinical routine.
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http://dx.doi.org/10.1016/s0939-3889(15)70541-6 | DOI Listing |
Med Phys
January 2025
Department of Radiation Oncology, Duke University, North Carolina, USA.
Background: The electronic compensation (ECOMP) technique for breast radiation therapy provides excellent dose conformity and homogeneity. However, the manual fluence painting process presents a challenge for efficient clinical operation.
Purpose: To facilitate the clinical treatment planning automation of breast radiation therapy, we utilized reinforcement learning (RL) to develop an auto-planning tool that iteratively edits the fluence maps under the guidance of clinically relevant objectives.
Vaccines (Basel)
January 2025
Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
Background/objectives: COVID-19 vaccines effectively prevent severe disease, but unequal distribution, especially in low- and middle-income countries, has led to vaccine-resistant strains. This highlights the urgent need for alternative vaccine platforms that are safe, thermostable, and easy to distribute. This study evaluates the immunogenicity, stability, and scalability of a dissolved microneedle array patch (MAP) delivering the rS1RS09 subunit vaccine, comprising the SARS-CoV-2 S1 monomer and RS09, a TLR-4 agonist peptide.
View Article and Find Full Text PDFVaccines (Basel)
January 2025
Institute of Immunization and Prevention, Zhejiang Center for Disease Control and Prevention, Hangzhou 310051, China.
: China has a high incidence rate of varicella yet a low coverage rate of the varicella vaccine (VarV), with safety concerns being a leading cause of the lack of vaccination willingness. This study aimed to describe VarV-related adverse events following immunization (AEFIs) and analyze their characteristics in Zhejiang, China, 2020-2022. : VarV-related AEFIs in Zhejiang Province from 1 January 2020 to 31 December 2022 were collected through the Chinese National AEFI Information System (CNAEFIS) for a descriptive epidemiological analysis.
View Article and Find Full Text PDFNanomaterials (Basel)
January 2025
Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1X6, Canada.
Monte Carlo (MC) simulations have become important in advancing nanoparticle (NP)-based applications for cancer imaging and therapy. This review explores the critical role of MC simulations in modeling complex biological interactions, optimizing NP designs, and enhancing the precision of therapeutic and diagnostic strategies. Key findings highlight the ability of MC simulations to predict NP bio-distribution, radiation dosimetry, and treatment efficacy, providing a robust framework for addressing the stochastic nature of biological systems.
View Article and Find Full Text PDFCurr Oncol
January 2025
Department of Radiation Oncology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
(1) Background: Volumetric modulated arc therapy (VMAT) can deliver more accurate dose distribution and reduce radiotherapy-induced toxicities for postoperative cervical and endometrial cancer. This study aims to retrospectively analyze the relationship between dosimetric parameters of organs at risk (OARs) and acute toxicities and provide suggestions for the dose constraints. (2) Methods: A total of 164 postoperative cervical and endometrial cancer patients were retrospectively analyzed, and the endpoints were grade ≥ 2 acute urinary toxicity (AUT) and acute lower gastrointestinal toxicity (ALGIT).
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