Gheorghe Iancu

Universitätsklinikum Gießen und Marburg | UKGM · Klinik für Strahlentherapie

Background: We retrospectively investigate feasibility and safety of whole brain radiotherapy (WBRT) including a simultaneous-integrated boost technique (WBRT-SIB) in a cohort of patients with a very poor prognosis suffering from multiple and/or large brain metastases, unfavorable primary histology, poor performance status and/or symptomatic BMs. M...

Radiotherapy is frequently used in the therapy of lymphoma. Since lymphoma, for example Hodgkin's disease, frequently affect rather young patients, the induction of secondary cancer or other long-term adverse effects after irradiation are important issues to deal with. Especially for mediastinal manifestations numerous organs and substructures at r...

A ripple filter (RiFi) is a passive energy modulator used in scanned particle therapy to broaden the Bragg peak, thus lowering the number of accelerator energies required for homogeneous target coverage, which significantly reduces the irradiation time. As we have previously shown, a new 6 mm thick RiFi with 2D groove shapes produced with 3D printi...

Purpose Raster scanning particle therapy offers potentially very conformal treatments. Limitation are long irradiation times and a sensitivity to intra-fractional motion. Passive energy modulators with an inhomogeneous mass distribution broaden the width of the mono-energetic Bragg peaks and reduce the accelerator energy shifts needed to homogeneou...

Purpose: Most treatment planning systems apply deterministic numerical algorithms for dose calculation and optimization, which are fast and reliable but show certain deficiencies when dealing with inhomogeneities. Monte Carlo simulations may improve these special cases. We report on a novel approach implementing an efficient Monte Carlo engine in t...

This report introduces a framework for comparing radiotherapy treatment planning in multicentric in silico clinical trials. Quality assurance, data incompatibility, transfer and storage issues, and uniform analysis of results are discussed. The solutions that are given provide a useful guide for the set-up of future multicentric planning studies or...

To present the first direct experimental in vitro comparison of the biological effectiveness of range-equivalent protons and carbon ion beams for Chinese hamster ovary cells exposed in a three-dimensional phantom using a pencil beam scanning technique and to compare the experimental data with a novel biophysical model. Cell survival was measured in...

A dynamic phantom has been developed to allow for measurement of 3D cell survival distributions and the corresponding distributions of the RBE-weighted dose (RBED) in the presence of motion. The phantom consists of two 96-microwell plates holding Chinese hamster ovary cells inside a container filled with culture medium and is placed on a movable st...

The software treatment planning for particles (TRiP) was extended by the functionality to calculate the clinically relevant RBE-weighted dose for scanned ion beams in the presence of motion. Calculations are based on 4D-CT and deformable registration. The underlying biological model is the local effect model. To validate the dose calculation algori...

Purpose: A beam tracking system for scanned ion beams was developed to compensate intrafractional motion. A novel method to calculate biologically effective doses for charged particles (especially carbon ions) in the presence of motion was implemented and experimentally validated. Method and Materials: The tracking system adapts pencil beam positio...

Aiming at an extension of the experimenting capabili-ties for nuclear structure physics at low momentum transfer at the superconducting Darmstadt electron linear accelera-tor S–DALINAC, a polarized electron gun is being con-structed. The new injector will be able to supply the S– DALINAC with 100 keV polarized electrons and should complement the pr...

Recent research and development for a polarized electron source (SPIN) for the recirculating superconducting elec-tron linear accelerator S-DALINAC will be presented. The polarized electron beam will be produced by photoemis-sion from an InAlGaAs/GaAs superlattice cathode and will be accelerated to 100 kV electrostatically. The results of the beam...

We have measured fragmentation cross-sections of Ar projectile nuclei at beam energy of 400 A MeV using experimental set-ups with plastic nuclear track detectors and different targets. In this paper total charge changing cross-sections and elemental fragmentation cross-sections for the production of fragments with charges ZF > or = 7 in interaction...

Fragmentation cross sections are essential input parameters for propagation calculations which describe the effect of shielding against cosmic ray heavy nuclei by the walls of spacecraft or planetary habitat. Cross sections for the breakup of different elements are needed for different types of target material and for a wide range of energy.For thi...