Back to Search
Start Over
Technique for routine output verification of Leipzig applicators with a well chamber
- Source :
- Medical Physics. 33:16-20
- Publication Year :
- 2005
- Publisher :
- Wiley, 2005.
-
Abstract
- The H-type Leipzig applicators are accessories of the microSelectron-HDR system (Nucletron, Veenendaal, The Netherlands) for treatment of superficial malignancies. Recently, the dose rate distributions in liquid water for the whole set of applicators using both source models available for the microSelectron-HDR afterloaders have been obtained by means of the experimentally validated Monte Carlo (MC) code GEANT4. Also an output table (cGy/hU) at 3 mm depth on the applicator central axis was provided. The output verification of these applicators by the user, prior to their clinical use, present practical problems: small detectors such as thermoluminescent dosimeters or parallel-plate ionization chambers are not easily used for verification in a clinical environment as they require a rigid setup with the Leipzig applicator and a phantom. In contrast, well-type ionization chambers are readily available in radiotherapy departments. This study presents a technique based on the HDR1000Plus well chamber (Standar Imaging) measurements with a special insert, which allows the output verification of the H-type Leipzig applicators on a routine basis. This technique defines correspondence factors (CF) between the in water dose rate output of the Leipzig applicators (cGy/hU) obtained with MC and the reading on the well chamber with the special insert, normalized to themore » HDR calibration factor with the HDR insert and to the source strength. To commission the applicators (with the well chamber and the special insert used), the physicist should check if the CF value agrees with its tabulated values presented in this work. If the differences are within 5% the tabulated output values can be used in clinical dosimetry. This technique allows the output validation of the Leipzig applicators with a well chamber widely used for HDR Ir-192 source strength measurements. It can easily be adapted to other types of well chambers for HDR source output verification.« less
- Subjects :
- Dosimeter
business.industry
Computer science
medicine.medical_treatment
Brachytherapy
chemistry.chemical_element
General Medicine
Thermoluminescence
Imaging phantom
Radiation therapy
Optics
chemistry
Medical imaging
Calibration
medicine
Dosimetry
Clinical dosimetry
Iridium
business
Dose rate
Nuclear medicine
Subjects
Details
- ISSN :
- 00942405
- Volume :
- 33
- Database :
- OpenAIRE
- Journal :
- Medical Physics
- Accession number :
- edsair.doi...........b7c0839210e7084df201fac0bf3cf803