An approximate correction method for the CT value-electron density curve of CBCT was established, through comparison and fitting with FBCT images, and applied to evaluate the therapeutic dose of IMRT. The precision of using CBCT for plan calculation was validated by comparing the dose distribution between CBCT- and FBCT-based IMRT plans. Also setup deviations were simulated to evaluate the ability of the CBCT-based calculation for detecting the dose errors caused by positioning deviation. The gamma comparison between CBCT- and FBCT-based dose computations showed that the pass rates of (2%, 2 mm) criteria were better than 97.60 ± 0.83% and 97.74 ± 2.08% in the phantom and 10 NPC cases. When setup deviation was introduced into CBCT-based dose calculation, the gamma pass rate significantly decreased while the volumetric doses of the targets and some normal organs exhibited different changes compared to the original plan. Our results validated the above CT value-electron density correction which reduced the difference between CBCT- and FBCT-based IMRT plan calculation for NPC to less than 2%. Online CBCT-based dose calculation can be used to reflect and evaluate the dose distribution discrepancy caused by setup deviation and structure changes during the treatment, ensuring more effective quality control of IMRT treatment.
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http://dx.doi.org/10.1155/2014/326532 | DOI Listing |
Cytotherapy
November 2024
Institute of Immunology and Immunotherapy, College of Medicine and Health, University of Birmingham, Birmingham, UK. Electronic address:
Background Aims: Extracellular vesicles (EVs) have gained traction as potential cell-free therapeutic candidates. Development of purification methods that are scalable and robust is a major focus of EV research. Yet there is still little in the literature that evaluates purification methods against potency of the EV product.
View Article and Find Full Text PDFInt J Pharm
January 2025
Department of Chemical and Biochemical Engineering, Rutgers University, Piscataway, NJ, 08854, USA; Center for Structured Organic Particulate Systems (C-SOPS), Cranbury, NJ, 08512, USA.
This study used Raman and near-infrared (NIR) spectroscopy to monitor small real-time changes in powder blends and tablets in low-dose pharmaceutical formulations. The research aims to enhance process analytical technology (PAT) in pharmaceutical manufacturing, ensuring high-quality and uniform products with applications to produce drugs with narrow therapeutic indices (NTI). The study utilizes Raman and NIR spatially resolved spectroscopy (SRS) techniques to monitor a moderate cohesive material's active pharmaceutical ingredient (API) concentrations during manufacturing.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, P. R. China.
Hexafluoropropylene oxide trimer acid (HFPO-TA, CF(CFOCF(CF))COOH) is widely used as an alternative to perfluorooctanoic acid (PFOA), but whether it is a safe alternative requires further evaluation. In this study, male mice were exposed to three dosages (0.56, 2.
View Article and Find Full Text PDFJ Nucl Med
January 2025
Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland; and.
The treatment regimen for [Lu]Lu-prostate-specific membrane antigen (PSMA) 617 therapy follows that of chemotherapy: 6 administrations of a fixed activity, each separated by 6 wk. Mathematic modeling can be used to test the hypothesis that the current treatment regimen for a radiopharmaceutical modality is suboptimal. A mathematic model was developed to describe tumor growth during [Lu]Lu-PSMA therapy.
View Article and Find Full Text PDFPhys Med Biol
January 2025
Department of Accelerator and Medical Physics, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, JAPAN.
The tumor microenvironment characterized by heterogeneously organized vasculatures causes intra-tumoral heterogeneity of oxygen partial pressure at the cellular level, which cannot be measured by current imaging techniques. The intra-tumoral cellular heterogeneity may lead to a reduction of therapeutic effects of radiation. The purpose of this study was to investigate the effects of the heterogeneity on biological effectiveness of H-, He-, C-, O-, and Ne-ion beams for different oxygenation levels, prescribed dose levels, and cell types.
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