Jörg Bohsung

• Dr
• Siemens Healthcare GmbH

The present invention relates generally to a method of displaying which treatment plan is administered at each fraction of a complete radiotherapy treatment, comprising displaying treatment plans P1 through Pn, receiving an input that designates which plan or multiple plans from plans P1 through Pn will be administered for each treatment day T1 thr...

Shielded p-silicon diodes, frequently applied in general photon-beam dosimetry, show certain imperfections when applied in the small photon fields occurring in stereotactic or intensity modulated radiotherapy (IMRT), in electron beams and in the buildup region of photon beam dose distributions. Using as a study object the shielded p-silicon diode P...

The purpose of this work was a comparison of realistic IMRT plans based on the same CT-image data set and a common predefined set of dose objectives for the planning target volume and the organs at risk. This work was part of the larger European QUASIMODO IMRT verification project. Eleven IMRT plans were produced by nine different European groups,...

IMRT necessitates extension of existing inter-centre quality assurance programs due to its increased complexity. We assessed the feasibility of an inter-centre verification method for different IMRT techniques. Eight European radiotherapy institutions of the QUASIMODO network, have designed an IMRT plan for a horseshoe-shaped PTV surrounding a cyli...

To determine the dose received by the unshielded testicles during a course of 20-MV conventional external-beam radiotherapy for patients with localized prostate cancer. Critical evaluation of the potential impact on fertility and hormonal impairment in these patients according to the literature. The absolute dose received by the testicles of 20 ran...

The implementation of intensity modulated radiotherapy (IMRT) for patients with prostate cancer in daily routine has been elaborated at our department. Our quality assurance (QA) concept is one method to pave the way for initiating IMRT treatments for starting institutions. A clinical quality assurance (CQA) procedure has been set-up for all patien...

Local failure is the one of the most frequent cause of tumor related death in locally advanced non-small cell lung cancer (LAD-NSCLC). Dose escalation has the promise of increased loco-regional tumor control but is limited by the tolerances of critical organs. To evaluate the potential of IMRT in comparison to conventional three-dimensional conform...

An increasing number of radiotherapy centres is now aiming for clinical implementation of intensity modulated radiotherapy (IMRT), but--in contrast to conventional treatment--no national or international guidelines for commissioning of the treatment planning system (TPS) and acceptance tests of treatment equipment have yet been developed. This pape...

Virchow-Robin's perivascular spaces lie between the basement membrane around pericytes and the basement membrane at the surface of the glia limitans of the brain vessels. They are directly connected to the subpial space and harbour a population of cells distinct from pericytes, perivascular microglia and other cells within perivascular spaces (e.g....

In radiation oncology more and more effort is taken to include the dose conformity to the target as well as the dose sparing of risk organs (OAR) and healthy tissue to the treatment planing. Conformal stereotactic radiosurgery and radiotherapy (CSRS and CSRT) offer the potential to optimise these parameters according to the demands of the physician...

To investigate the influence of implementing three-dimensional treatment planning on staffing needs, valid questionnaire responses from 22 radiotherapy institutions have been evaluated. Average time requirements per plan rise from 213 to 439 min upon implementation, but with experience decrease to 317 min. No institution reports additional staff po...

Die Segmentierung von Schnittbildserien spielt bei der Definition von Zielvolumen und Risikoorganen für die 3D-Bestrahlungsplanung eine große Rolle. In dieser Arbeit wird eine Methode zur Quantifizierung der rein technisch bedingten Ungenauigkeit bei der manuellen Bildsegmentierung beschrieben. Zur Validierung dieser Methode wurde ein Graustufenpha...

To assist in the design of quality assurance activities of 3D treatment planning systems (TPSs), a postal survey has been carried out, addressing TPS users on quality characteristics and their relative importance in clinical routine planning. The approach as described in ISO/IEC 9126 has been used to analyze TPS quality. Both TPS quality characteri...

We compiled a table of all major, minor, and trace-element abundances in 89 interplanetary dust particles (IDPs) that includes data obtained with proton-induced x-ray emission (PIXE), synchroton x-ray fluorescence (SXRF), and secondary ion mass spectrometry (SIMS). For the first time, the reliability of the trace-element abundances in IDPs is teste...

The distribution of free cytosolic Ca2+ was studied during somatic embryogenesis of carrot using confocal scanning laser microscopy with fluo-3 as a fluorescent Ca2+ indicator. Chlorotetracycline fluorescence, antimonate precipitation and proton induced X-ray emission analysis were used as additional methods to confirm the results obtained with flu...

The new proton microprobe is characterized by modular mounting resulting in easy maintenance, low cost personal computer (PC) system and several new features. The most important of these being the design of the lens, its location inside the vacuum, and an elaborate system for beam monitoring. The PC system allows for all kinds of standard data acqu...

Previous spectral analyses have given evidence of collisionally excited Jovian and (at times) Saturnian H2 Werner bands being absorbed by hydrocarbons at the shortest wavelengths along the auroral ovals, and of a longitudinal dependence of this absorption in the Jovian aurorae. This “color ratio” has been used to estimate the energy of the primary...

Besides meteorites and lunar material, interplanetary dust particles (IDPs) collected in the stratosphere represent another form of extraterrestrial matter available for studies in the laboratory. One major goal of IDP research activities is the search for an IDP classification scheme based on their chemical composition that is obtained by modern m...

In contributing to a complete Interplanetary Dust Particle (IDP) chemical dataset we measured the bulk chemistry of six chondritic IDPs from collector L2005 with the new Heidelberg micron-Proton Induced X Ray Emission (PIXE). The results are given normalized to Fe and CI. While particles B11, C18, C34, and C35 were measured intact, B12 and E28 frag...

For 20 years stratospheric interplanetary dust particles (IDPs) have been analyzed by various methods, but the main questions remain: What can we really learn from their study? What is the parent body of an individual particle? Comets are the main dust producer in the solar system, but in the Earth's orbit the asteroidal interplanetary dust compone...

Excitation of characteristic X-rays in a sample by 2-4 MeV protons (Proton Induced X-ray Emission, PIXE) enables the non- destructive detection of elements with Z >= 12 with high sensitivity [1]. In conjunction with a focused proton beam provided by the proton microprobe such measurements are possible with a spatial resolution in the micrometer ran...

Interplanetary dust particles (IDPs) collected in the stratosphere provide new information on the chemical and isotopic composition of material in the vicinity of the Earth and thus possibly of asteroids and comets. The available data on major, minor and trace element abundances, mainly obtained with PIXE and SYXFA, suggest the presence of at least...

There are several incentives to identify the analogues of dislocations and disclinations in quasicrystals. Penrose patterns are two-dimensional systems, and according to phase space counting fluctuations of the atomic displacements are so strong that exact long-range order is reduced to quasi-longrange order just as in periodic crystals. The necess...

The most significant feature in the transition from the quasicrystalline to the amorphous state is the loss of long-range bond-orientational order. Disclinations are candidates for elementary excitations which destroy angular correlations. Generalizing the topological defect classification, we investigate point singularities in two-dimensional pent...

The most significant feature in the transition from the quasi-crystalline to the amorphous state is the loss of long-range bond-orientational order. Disclinations are candidates for elementary excitations which destroy angular correlations. Generalizing the topological defect classification, point singularities in two-dimensional pentagonal quasi-c...

The most significant feature in the transition from the quasicrystalline to the amorphous state is the loss of long-range bond-orientational order. Disclinations are candidates for elementary excitations which destroy angular correlations. Generalizing the topological defect classification, we investigate point singularities in two-dimensional pent...

Mikroreprod. eines Ms. Getr. Zählung : Ill., graph. Darst. Heidelberg, Universiẗat, Diss., 1993.