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Abstract: Normoxic polymer gel dosimeters are studied, with the aim of achieving a valid and advantageous method for in-phantom 3D dose determinations. Developments were carried out in the application of such dosimetric material to the method based on dosimeter gel layers that has shown good reliability for absorbed dose imaging in radiotherapy. The technique has been improved, in particular taking care of minimizing the oxygen infiltration into the gel matrix in order to suitably avoid its effect of inhibiting the polymerization process after exposure. A suitable choice of the material of dosimeter walls has brought to achieve good steadiness in time of dosimeter sensitivity and satisfactory results in dose imaging and depth-dose profiling. [Copyright &y& Elsevier]

Abstract: Gel dosimeters in the form of layers are a promising tool for in-phantom absorbed dose imaging in radiotherapy, either with high gradient X-ray or electron radiation fields, as in conformal radiotherapies, or with neutron beams, as in boron neutron capture therapy (BNCT). A normoxic polymer gel has been studied, and the results are compared with those obtained with Fricke gel dosimeters exposed to the same fields and in the same phantom configuration. Although promising, polymer gel layers need further improvements in order to obtain higher reliability. [Copyright &y& Elsevier]

Abstract: The reliability for radiotherapy applications of a normoxic-polymer gel dosimeter, analysed by means of optical methods, was studied. The optical transmittance was measured with a spectrophotometer and imaged with a CCD camera. The characteristics of sensitivity, spatial resolution, image stability, linearity of the response and reproducibility were investigated and analysed. Radiation induces a radical polymerisation in the gel matrix and the resulting macromolecules remain fixed in space making therefore possible the absorbed dose imaging. [Copyright &y& Elsevier]

Abstract: A thorax phantom has been designed, consisting of PMMA and PE plates containing a cavity filled with a laboratory-made lung-substitute. Fricke-gel dosimeters have been placed in the lung-substitute volume, and the phantom has been irradiated at the epithermal column of LVR-15 reactor. Absorbed dose images have been obtained for both gamma radiation and charged particles emitted in the 10B reactions with thermal neutrons. Measurements with thermoluminescence dosimeters (TLDs) and Monte Carlo (MC) calculations have been performed too, in order to attain inter-comparison of results. [Copyright &y& Elsevier]

Abstract: Gel dosimeters in form of layers have shown noticeable potentiality for in-phantom dose profiling and imaging in BNCT neutron fields. Such dosimeters give the possibility of achieving spatial dose distributions of each dose contribution in neutron fields. The various dose components are separated by means of pixel-to-pixel manipulations of pairs of images acquired with gel dosimeters having different isotopic compositions. The reliability of polymer-gel-layer dosimeters (PGLD) for BNCT has been studied and their utilisation limits have been inspected. [Copyright &y& Elsevier]

Abstract: Gamma and fast neutron dose spatial distributions have been measured at the collimator exit of the epithermal neutron beam of LVR-15 reactor (Řež). Measurements were performed by means of optically analyzed Fricke-gel-layer detectors. The separation of the two dose contributions has been achieved by suitable pixel-to-pixel elaboration of the light transmittance images of Fricke-gel-layer detectors prepared with water and heavy water. [Copyright &y& Elsevier]

Abstract: The measurement of both gamma dose and thermal neutron fluence in a BNCT gamma–neutron mixed-field can be achieved by means of a single thermoluminescence dosimeter (TLD-700), exploiting the shape of the glow-curve (GC). The method is based on simple algorithms containing parameters obtained from the TLD-700GC and requires the gamma calibration GC (for gamma dose measurement) or the thermal neutron calibration GC (for neutron fluence measurement) and moreover the GC of a TLD-600 exposed to a BNCT field, uncalibrated. Some results are reported, showing the potentiality of the method. [Copyright &y& Elsevier]