INVESTIGADORES
VALENTE Mauro Andres
congresos y reuniones científicas
Título:
Dose Imaging in photon radiotherapy with Fricke and normoxic-polymer gels
Autor/es:
G. GAMBARINI, D. BRUSA M. CARRARA, G. CASTELLANO M. MARIANI , S. TOMATIS M. VALENTE E. VANOSSI
Lugar:
Pavia, Italia
Reunión:
Congreso; 19th. EPS Nuclear Physics Division Conference ? New Trends in Nuclear Physics and Applications; 2005
Resumen:
Abstract. Gel dosimeters are integrating dosimeters, that enable dose verification in three dimensions. Optical
analysis of gel dosimeters has demonstrated to be an available technique for imaging the absorbed in-phantom
dose exposed to radiotherapy beams. The goal is to demonstrate the ability of gel dosimeters to achieve
accurately and spatial resolution in dose mapping, also when high dose regions are produced by a complex three
dimensional treatment planning. Two types of dosimeters are investigated, a Fricke gel (Fricke-Xylenol-orangeinfused
gel) and a normoxic-polymer gel (polyacrylamide gel). Dosimeter gel samples of different shapes were
exposed to photon fields, at various energies. Transmittance images were taken by means of a CCD camera and
a spectrophotometer. In phantom 3-D images were realised with both dosimeter gels. An irradiation, using a
linear accelerator, was realised in order to validate the method and techniques. Central axis depth dose profiles of
the phantom were extracted and compared with ionization chamber measurements. Tissue-equivalence and other
properties for both gels were studied using Monte Carlo techniques. Off-axis profiles and three dimensional dose
distribution were obtained by simulations and compared with experimental dose distributions.. Gel dosimeters are integrating dosimeters, that enable dose verification in three dimensions. Optical
analysis of gel dosimeters has demonstrated to be an available technique for imaging the absorbed in-phantom
dose exposed to radiotherapy beams. The goal is to demonstrate the ability of gel dosimeters to achieve
accurately and spatial resolution in dose mapping, also when high dose regions are produced by a complex three
dimensional treatment planning. Two types of dosimeters are investigated, a Fricke gel (Fricke-Xylenol-orangeinfused
gel) and a normoxic-polymer gel (polyacrylamide gel). Dosimeter gel samples of different shapes were
exposed to photon fields, at various energies. Transmittance images were taken by means of a CCD camera and
a spectrophotometer. In phantom 3-D images were realised with both dosimeter gels. An irradiation, using a
linear accelerator, was realised in order to validate the method and techniques. Central axis depth dose profiles of
the phantom were extracted and compared with ionization chamber measurements. Tissue-equivalence and other
properties for both gels were studied using Monte Carlo techniques. Off-axis profiles and three dimensional dose
distribution were obtained by simulations and compared with experimental dose distributions.