A5000511985- Advanced Radiotherapy Techniques
- Radiation Therapy and Dosimetry
- Radiation Detection and Scintillator Technologies
- Medical Imaging Techniques and Applications
- Ocular Oncology and Treatments
- Radiation Dose and Imaging
- Nuclear Physics and Applications
- Advanced X-ray and CT Imaging
- Quantum, superfluid, helium dynamics
- Nuclear reactor physics and engineering
- Glioma Diagnosis and Treatment
- Advanced Optical Sensing Technologies
- Radiation Effects and Dosimetry
- Nonmelanoma Skin Cancer Studies
- Carbon Nanotubes in Composites
- Effects of Radiation Exposure
- Particle accelerators and beam dynamics
- Radioactivity and Radon Measurements
- Lung Cancer Diagnosis and Treatment
- Particle Detector Development and Performance
- Lymphoma Diagnosis and Treatment
- Radiopharmaceutical Chemistry and Applications
- Childhood Cancer Survivors' Quality of Life
- Breast Cancer Treatment Studies
- Radiomics and Machine Learning in Medical Imaging
University of Duisburg-Essen
2011-2024
West German Heart and Vascular Center Essen
2019-2024
Deutschen Konsortium für Translationale Krebsforschung
2023
Essen University Hospital
2011-2020
Ruhrlandklinik
2009-2018
University of Aveiro
2018
Universitätsklinik für Strahlentherapie
2016
Endesa (Spain)
2009-2013
Hospital General Universitario De Valencia
2010
Universitat de Barcelona
2007-2009
PurposeTo present the American Brachytherapy Society (ABS) guidelines for plaque brachytherapy of choroidal melanoma and retinoblastoma.Methods MaterialsAn international multicenter Ophthalmic Oncology Task Force (OOTF) was assembled to include 47 radiation oncologists, medical physicists, ophthalmic oncologists from 10 countries. The ABS-OOTF produced collaborative guidelines, based on their eye cancer–specific clinical experience knowledge literature. This work reviewed approved by ABS...
Purpose: Two new codes, PEN E ASY and L INAC , which automate the Monte Carlo simulation of Varian Clinacs 600, 1800, 2100, 2300 series, together with their electron applicators multileaf collimators, are introduced. The challenging case a relatively small far‐from‐axis field has been studied these tools. Methods: is modular, general‐purpose main program for PENELOPE system that includes various source models, tallies variance‐reduction techniques (VRT). code geometry model allows...
Improvements beyond the primitive approximation in path integral Monte Carlo method are explored both a model problem and real systems. Two different strategies studied: The Richardson extrapolation on top of data Takahashi-Imada action. extrapolation, mainly combined with action, always reduces number-of-beads dependence, helps determining approach to dominant power law behavior, all without additional computational cost. action has been tested two hard-core interacting quantum liquids at...
Purpose: Phase-space files for Monte Carlo simulation of the Varian TrueBeam beams have been made available by Varian. The aim this study is to evaluate accuracy distributed phase-space flattening filter free (FFF) beams, against experimental measurements from ten Linacs. Methods: used as input in PRIMO, a recently released program based on thePENELOPE code. Simulations 6 and 10 MV FFF were computed virtual water phantom field sizes 3 × 3, 6, cm2 using 1 mm3 voxels 20 40 with 2 voxels....
The availability of photon and electron spectra in digital form from current accelerators Monte Carlo (MC) systems is scarce, one the packages widely used refers to linacs with a reduced clinical use nowadays. Such are mainly intended for MC calculation detector-related quantities conventional broad beams, where detailed phase-space files (PSFs) less critical than MC-based treatment planning applications, but unlike PSFs, can easily be transferred other computer users.A set range Varian has...
Proton therapy enables to deliver highly conformed dose distributions owing the characteristic Bragg peak and finite range of protons. However, during proton therapy, secondary neutrons are created, which can travel long distances deposit in out-of-field volumes. This absorbed needs be considered for radiation-induced cancers, particularly relevant case pediatric treatments. Unfortunately, no method exists clinics computation therapy. To help overcome this limitation, a computational tool...
We investigate possible usage of single-walled carbon nanotubes (SWNTs) as an efficient storage and separation device hydrogen−methane mixtures at room temperature. The study has been done using Grand Canonical Monte Carlo simulations for modeling in idealized SWNTs bundles. These have studied several pressures, up to 12 MPa. found that the values stored volumetric energy equilibrium selectivity greatly depend on chiral vector (i.e., pore diameter) nanotubes. bundle formed by [5,4] (nanotube...
A technique for accelerating the simulation of multileaf collimators with Monte Carlo methods is presented. This technique, which will be referred to as movable-skin method, based on geometrical modifications that do not alter physical shape leaves, but affect logical way in code processes geometry. Zones geometry from secondary radiation can emerge are defined skins and transport throughout these zones simulated accurately, while non-skin modelled approximately. The method general applied...
A method based on a combination of the variance-reduction techniques particle splitting and Russian roulette is presented. This improves efficiency radiation transport through linear accelerator geometries simulated with Monte Carlo method. The named as 'splitting-roulette' was implemented code tested an Elekta linac, although it general enough to be any other general-purpose linac geometry. Splitting-roulette uses following two modes splitting: simple 'selective splitting'. Selective new...
Monte Carlo simulation of linear accelerators (linacs) depends on the accurate geometrical description linac head. The geometry Varian TrueBeam is not available to researchers. Instead, company distributes phase-space files flattening-filter-free (FFF) beams tallied at a plane located just upstream jaws. Yet, simulations based third-party phase spaces are subject limitations. In this work, an experimentally developed for FFF presented. model uses information provided by that reveals large...
Abstract Background Monte Carlo simulation of radiation transport for medical linear accelerators (linacs) requires accurate knowledge the geometrical description linac head. Since geometry Varian TrueBeam machines has not been disclosed, manufacturer distributes phase-space files patient-independent part to allow researchers compute absorbed dose distributions using method. This approach limits possibility achieving an arbitrarily small statistical uncertainty. work investigates use Clinac...
Water/medium stopping-power ratios, s(w,m), have been calculated for several ICRP and ICRU tissues, namely adipose tissue, brain, cortical bone, liver, lung (deflated inflated) spongiosa. The considered clinical beams were 6 18 MV x-rays the field size was 10 x cm(2). Fluence distributions scored at a depth of cm using Monte Carlo code PENELOPE. collision stopping powers studied tissues evaluated employing formalism Report 37 (1984 Stopping Powers Electrons Positrons (Bethesda, MD: ICRU))....
For the treatment of conjunctival lymphoma in early stages, external beam radiotherapy offers a curative approach. Such requires use highly conformed small radiation beams. The size is so that even advanced planning systems have difficulties calculating dose distributions. One possible approach for optimizing technique and later performing by means full Monte Carlo (MC) simulations. In this paper, we compare experimental absorbed profiles obtained with collimator used at University Hospital...
Background and purpose PENH is a recently coded module for simulation of proton transport in conjunction with the Monte Carlo code PENELOPE. PENELOPE applies class II to all type interactions, particular, elastic collisions. uses calculated differential cross sections collisions that include electron screening effects as well nuclear structure effects. Proton‐induced reactions are simulated from information ENDF‐6 database or alternative databases ENDF format. The this work benchmark by...
Water is the reference medium for radiation therapy dosimetry, but film dosimetry it more practical to use a solid phantom. As composition of phantoms differs from that water, energy dependence exposed within may also differ. The radiochromic given beam quality Q (energy monoenergetic beams) has two components: intrinsic and absorbed-dose f(Q), latter which can be calculated through Monte Carlo simulation transport. authors used simulations study influence phantom material on f(Q) EBT3...
The PRIMO system is a computer software that allows the Monte Carlo simulation of linear accelerators and estimation subsequent absorbed dose distributions in phantoms computed tomographies. aim this work to validate methods incorporated evaluate deviations introduced by errors positioning leaves multileaf collimator recorded dynalog files during patient treatment.The reconstruction treatment plans from Varian's was implemented system. Dose were estimated for volumetric-modulated arc therapy...
We report on the efficiency calibration of a HPGe x-ray detector using radioactive sources and an analytical expression taken from literature, in two different arrangements, with without broad-angle collimator. The frontal surface Ge crystal was scanned pencil beams photons. dead layer found to be nonuniform, central intermediate regions that have thin (μm range) thick (mm layers, respectively, surrounded by insensitive ring. discuss how this fact explains observed curves generalize adopted...
<b><i>Background/Aims:</i></b> Ruthenium plaques are used for the treatment of ocular tumors. There is, however, a controversy regarding maximum treatable tumor height. Some advocate eccentric plaque placement, without posterior safety margin, to avoid collateral damage fovea and optic disc, but this has raised concerns about marginal recurrence. is need quantitative information on spatial absorbed dose distribution in adjacent tissues. We have overcome obstacle using...