Abstract:
:In this paper we present the results of a dosimetric evaluation of a 2D ionization chamber array with the objective of its implementation for quality assurance in clinical routine. The pixel ionization chamber MatriXX (Scanditronix Wellhofer, Germany) consists of 32x32 chambers with a distance of 7.6 mm between chamber centres. The effective depth of measurement under the surface of the detector was determined. The dose and energy dependence, the behaviour of the device during its initial phase and its time stability as well as the lateral response of a single chamber of the detector in cross-plane and diagonal directions were analysed. It could be shown, that the detector's response is linear with dose and energy independent. Taking the lateral response into account, two different dose profiles, for a pyramidal and an IMRT dose distribution, were applied to compare the data generated by a treatment planning system with measurements. From these investigations it can be concluded that the detector is a suitable device for quality assurance and 2D dose verifications.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Herzen J,Todorovic M,Cremers F,Platz V,Albers D,Bartels A,Schmidt Rdoi
10.1088/0031-9155/52/4/023subject
Has Abstractpub_date
2007-02-21 00:00:00pages
1197-208issue
4eissn
0031-9155issn
1361-6560pii
S0031-9155(07)32387-7journal_volume
52pub_type
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