Dosimetry using radiosensitive gels in radiotherapy: Significance and methods

The goal of conformal radiotherapy is to concentrate the dose in a well-def ined volume by avoiding the neighbouring healthy structures. This technique requires powerful treatment planning software and a rigorous control of es timated dosimetry. The usual dosimetric tools are not adapted to visualize and validate complex 3D treatment. Dosimetry by radiosensitive gel permits visualization and measurement of the three-dimensional dose distribution. T he objective of this work is to report on current work in this field and, b ased on our results and our experience, to draw prospects for an optimal us e of this technique. Further developments will relate to the realization of new radiosensitive gels satisfying, as well as possible, cost requirements , easy realization and use, magnetic resonance imagery (MRI) sensitivity, t issue equivalence, and stability. Other developments focus on scanning meth ods, especially in MRI to measure T1 and T2.