Development of tissue-equivalent materials

Abstract

Tissue-equivalent materials, or phantoms, are used in research laboratories and in clinical settings as part of quality control and radioprotection routines and are critical to avoid exposing people to unnecessary radiation doses. Currently there are around 127,000 diagnostic imaging equipment distributed throughout the country and, according to the current legislation, all should be subject to a quality control program. Currently, with the improvement of professionals in the area of Medical Physics, the country counts on qualified professionals for the implementation of these programs. The remaining link to the amplified diffusion of these important procedures is the reduction of costs of the necessary instrumentation, which passes through the field of technologies as proposed in this project. Thus, the main objectives of the project are the development and validation of radiologically equivalent materials to human tissues in order to compose commercial products that can be used in routine quality control and radiation dosimetry in diagnostic imaging facilities. The proposal makes use of a mathematical methodology previously developed to obtain formulations for tissue-equivalent materials. In this methodology, the total attenuation coefficient of the developed material is adjusted to the reference material by the least squares method in an energy interval that depends on the purpose of the phantom. This methodology was used to obtain formulations of materials equivalent to water, in the energy range used in radiodiagnostic (10 - 150keV) tests and for breast tissue simulating materials, using the energy interval (5 - 45keV).An important part of the proposal consists in the physical construction of these materials, which implies overcoming several challenges, as well as their validation through rigorous laboratory tests and evaluations in clinical diagnostic imaging equipment. As a result of this process, we intend to arrive, at the end of Phase I of the project, with a set of samples of radiologically equivalent materials to human tissues with potential applications in quality control and radiation dosimetry of general radiology, mammography and tomography equipment computerized. Positive results in terms of technical and commercial viability of these materials may indicate a good opportunity for innovative development for the composition of a Phase II and III proposal. The main impact of these potential results is the improvement of the quality of the diagnostic images resulting from the amplification of the culture of application of quality control programs, as well as the reduction of the radiation doses resulting from the accomplishment of these examinations. Thus, in the medium term, it is expected to improve the diagnostic quality to identify diseases with greater protection to patients. (AU)