Development of a high-precision xyz-measuring table for the determination of the 3D dose rate distributions of brachytherapy sources.
An xyz-measuring table with a modular design has been developed for the determination of the individual 3D dose rate distributions of different brachytherapy sources requiring a high spatial resolution and reproducibility. The instrumental setup consists of a plastic scintillator detector system and the xyz-measuring table for guiding the detector across the radioactive sources. For this purpose, a micro positioning system with piezo inertial drives is chosen, providing a step width of 450 nm. To ensure a high reproducibility and accuracy better than 1 μm, an exposed linear encoder controls the positioning. The successful operation of the xyz-measuring table is exemplarily shown by measurements of dose profiles of two brachytherapy sources, an ophthalmic plaque and a radioactive seed. The setup allows a fully automated quality assurance of ophthalmic plaques and radioactive seeds under clinical conditions and can be extended to other (brachytherapy) sources of similar dimensions.
Fakultät Physik, Technische Universität Dortmund, Dortmund, Germany. marion.eichmann@tu-dortmund.de
M
M
Eichmann
T
T
Krause
D
D
Flühs
B
B
Spaan
D001918:Brachytherapy / Q000295:instrumentation*; D004867:Equipment Design; D005128:Eye Diseases / Q000532:radiotherapy; D011874:Radiometry / Q000295:instrumentation*