Purpose: The influence of the Integral Quality Monitor (IQM) transmission detector on photon beam properties was evaluated in a preclinical phase, using data from nine participating centres: (i) the change of beam quality (beam hardening), (ii) the influence on surface dose, and (iii) the attenuation of the IQM detector.
Methods: For 6 different nominal photon energies (4 standard, 2 FFF) and square field sizes from 1×1cm to 20×20cm, the effect of IQM on beam quality was assessed from the PDD values obtained from the percentage dose depth (PDD) curves, measured with and without IQM in the beam path. The change in surface dose with/without IQM was assessed for all available energies and field sizes from 4×4cm to 20×20cm. The transmission factor was calculated by means of measured absorbed dose at 10cm depth for all available energies and field sizes.
Results: (i) A small (0.11-0.53%) yet statistically significant beam hardening effect was observed, depending on photon beam energy. (ii) The increase in surface dose correlated with field size (p<0.01) for all photon energies except for 18MV. The change in surface dose was smaller than 3.3% in all cases except for the 20×20cm field and 10MV FFF beam, where it reached 8.1%. (iii) For standard beams, transmission of the IQM showed a weak dependence on the field size, and a pronounced dependence on the beam energy (0.9412 for 6MV to 0.9578 for 18MV and 0.9440 for 6MV FFF; 0.9533 for 10MV FFF).
Conclusions: The effects of the IQM detector on photon beam properties were found to be small yet statistically significant. The magnitudes of changes which were found justify treating IQM either as tray factors within the treatment planning system (TPS) for a particular energy or alternatively as modified outputs for specific beam energy of linear accelerators, which eases the introduction of the IQM into clinical practice.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.zemedi.2016.10.001 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Significant abundance of bacterial flagellin and expression of its surface localized receptor toll-like receptor 5 and cytokine interleukin-22 in South African infants with poor oral rotavirus vaccine take.
Gut Pathog
January 2025
Diarrheal Pathogens Research Unit (DPRU), Department of Virology, Sefako Makgatho Health Sciences University, Ga-rankuwa, Pretoria, South Africa.
Bacterial flagellin, a potent intestinal innate immune activator, prevents murine rotavirus (RV) infection independent of adaptive immunity and interferons. The flagellin-induced immunity is mediated by Toll-like receptor (TLR5) and Nod-like receptor C4 (NLRC4), which elicit the production of interleukins 22 (IL-22) and IL-18, respectively. Here, we assessed whether a high abundance of flagellin at the time of vaccination would negatively affect the oral RV vaccine take.
View Article and Find Full Text PDFEvaluation of ozonated and ultrasonically treated corn starch as an adsorbent for patulin in buffer solutions.
Sci Rep
January 2025
Department of Food Toxicology and Contaminant, National Research Centre, Dokki, Giza, Egypt.
This study evaluates the potential of ozonated corn starch (OCS) and ultrasonicated ozonated corn starch (USOCS) as adsorbents for patulin removal in buffer solutions. The results indicated that dual modification significantly altered the starch's structure, introducing functional groups such as carbonyl and carboxyl groups, and increasing its surface area. These modifications led to enhanced patulin adsorption capacity.
View Article and Find Full Text PDFPhase I study of BMS-986299, an NLRP3 agonist, as monotherapy and in combination with nivolumab and ipilimumab in patients with advanced solid tumors.
J Immunother Cancer
January 2025
Investigational Cancer Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
Purpose: BMS-986299 is a first-in-class, NOD-, LRR-, and pyrin-domain containing-3 (NLRP3) inflammasome agonist enhancing adaptive immune and T-cell memory responses.
Materials And Methods: This was a phase-I (NCT03444753) study that assessed the safety and tolerability of intra-tumoral BMS-986299 monotherapy (part 1A) and in combination (part 1B) with nivolumab, and ipilimumab in advanced solid tumors. Reported here are single-center results.
A novel and high-performance tumor inhibitor of La, N co-doped carbon dots for U251 and LN229 cells.
Colloids Surf B Biointerfaces
January 2025
Department of Neurosurgery, The Affiliated Ganzhou Hospital, Jiangxi Medical College, Nanchang University, Ganzhou 341000, China. Electronic address:
To address the medical challenges posed by glioblastoma, a novel and high-performance tumor inhibitor (La@FA-CDs) composed of folic acid and lanthanum nitrate hexahydrate, was successfully synthesized and demonstrated effectiveness in inhibiting the growth of U251 and LN299 cells. The microstructure of La@FA-CDs was extensively analyzed by FTIR, UV-Vis, XPS, TEM, AFM NMR, and nanoparticle size analyzer. The optical and electrical properties of La@FA-CDs were characterized using a fluorescence spectrometer and a zeta potential analyzer.
View Article and Find Full Text PDFA robust auto-contouring and data augmentation pipeline for adaptive MRI-guided radiotherapy of pancreatic cancer with a limited dataset.
Phys Med Biol
January 2025
Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, Downs Road, Sutton, London, Surrey, SM2 5PT, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND.
This study aims to develop and evaluate a fast and robust deep learningbased auto-segmentation approach for organs at risk in MRI-guided radiotherapy of pancreatic cancer to overcome the problems of time-intensive manual contouring in online adaptive workflows. The research focuses on implementing novel data augmentation techniques to address the challenges posed by limited datasets. Approach: This study was conducted in two phases.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!