For a start, although integral dose is generally assumed to be improved by the use of higher energy photons, there is concern that some treatment planning systems might not effectively model the “beam narrowing” at depth observed with high energy photons in the small radiation beamlets encountered in IMRT. This phenomenon is caused by lateral beam degradation due to penumbra widening (8); when ...

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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 detecto...

Radiochromic film has become an important tool to verify dose distributions in highly conformal radiation therapy such as IMRT. Recently, a new generation of these films, EBT3, has become available. EBT3 has the same composition and thickness of the sensitive layer of the previous EBT2 films, but its symmetric layer configuration allows the user to eliminate side orientation dependence, which i...