Michael Schwedas

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PURPOSE Test and comparison of various 2-D real-time detectors for dosimetric quality assurance (QA) of intensity-modulated radiotherapy (IMRT) with the vision to replace radiographic films for 2-D dosimetry. MATERIAL AND METHODS All IMRT treatment plans were created with the Konrad software (Siemens OCS). The final dose calculation was also carried out(More)
With three-dimensional conformal intensity-modulated radiotherapy (3D-c-IMRT) a heterogeneous dose distribution can be achieved in both planning treatment volume and in adjacent normal tissues and organs to be spared. 3D-c-IMRT demands for modified photon fluence profiles which can be accomplished with different techniques. This report deals with the(More)
PURPOSE To quantify the relative peripheral photon doses (PD) to healthy tissues outside the treated region for different IMRT technologies and linac head designs. MATERIAL AND METHODS Measurements were performed on an Elekta linac for various energies (6 MV, 10 MV, 25 MV) at different depths at a distance of 29 cm off-axis (vertical measurements) and(More)
To quantify the relative peripheral doses (PD) to healthy tissues outside the treated region for different intensity-modulated radiotherapy (IMRT) technologies. On a linear accelerator (linac) Oncor Impression (Siemens OCS) with two photon energies (6 MV, 15 MV), point dose measurements were performed at different depths in a solid phantom at 29 cm off-axis(More)
The use of intensity modulated radiation fields needs an extended quality assurance concept. This consists of a linac related part and a case related part. Case related means the verification of an individual treatment plan, optimized on a CT data set of an individual patient and prepared for the treatment of this patient. This part of the quality assurance(More)
The irradiation with intensity-modulated fields is possible with static as well as dynamic methods. In our university hospital, the intensity-modulated radiotherapy (IMRT) with compensators was prepared and used for the first time for patient irradiation in July 2001. The compensators consist of a mixture of tin granulate and wax, which is filled in a(More)
We compared different image-guidance (IG) strategies for prostate cancer with high-precision IG intensity-modulated radiation therapy (IMRT) using TomoTherapy® (Accuray Inc., Madison, WI, USA) and linear accelerator (LINAC)-IMRT and their impact on planning target volume (PTV) margin reduction. Follow-up data showed reduced bladder toxicity in TomoTherapy(More)
Test and comparison of various 2–D real–time detectors for dosimetric quality assurance (QA) of intensity–modulated radiotherapy (IMRT) with the vision to replace radiographic films for 2–D dosimetry. All IMRT treatment plans were created with the Konrad software (Siemens OCS). The final dose calculation was also carried out in Konrad. A Mevatron Primus(More)