Heavy metal in radiation therapy: A simple method to differentiate hip prosthesis materials.

Background: In recent years, the number of hip replacement patients receiving radiation therapy has steadily increased. In parallel, strategies have been developed to reduce metal artifacts in computed tomography (CT) images and improve the accuracy of dose calculation algorithms. However, in certain situations, knowledge of the type of prosthesis material is required to accurately determine the dose distribution.

Post-mastectomy radiotherapy: Impact of bolus thickness and irradiation technique on skin dose.

Purpose: To determine 10 MV IMRT and VMAT based protocols with a daily bolus targeting a skin dose of 45 Gy in order to replace the 6 MV tangential fields with a 5 mm thick bolus on alternate days method for post-mastectomy radiotherapy.

Method: We measured the mean surface dose along the chest wall PTV as a function of different bolus thicknesses for sliding window IMRT and VMAT plans. We analyzed surface dose profiles and dose homogeneities and compared them to our standard 6 MV strategy.

Experimental determination of magnetic field correction factors for ionization chambers in parallel and perpendicular orientations.

Magnetic field correction factors are needed for absolute dosimetry in magnetic resonance (MR)-linacs. Currently experimental data for magnetic field correction factors, especially for small volume ionization chambers, are largely lacking. The purpose of this work is to establish, independent methods for the experimental determination of magnetic field correction factors [Formula: see text] in an orientation in which the ionization chamber is parallel to the magnetic field.

TransitQA - A new method for transit dosimetry of Tomotherapy patients.

Purpose: TransitQA is an innovative method for Tomotherapy transit dosimetry using the on-board detector (OBD). Our previously published model for Tomotherapy treatment plan verification (AirQA) has been enhanced to take into account patient and couch transmission. AirQA estimates the OBD signal during irradiation with nothing in the beam path from the leaf control sinogram, allowing us to check whether the planned treatment is correctly delivered by the machine.

An efficient procedure for tomotherapy treatment plan verification using the on-board detector.

In this work, a fast and simple procedure for tomotherapy treatment plan verification using the on-board detector (OBD) has been developed. This procedure allows verification of plans with static and dynamic jaws (TomoEDGE). A convolution-based calculation model has been derived in order to link the leaf control sinogram from the treatment planning system to the data acquired by the OBD during a static couch procedure.