| Solvers: Hubálková Hana (Charles University in Prague), Starčuk Zenon (Institute of Scientific Instruments of the AS CR),date: 01:10:2004 - 31:12:2006. Magnetic resonance (MR) imaging (MRI) is considered a top radiodiagnostic method today. MRI examination of a patient is used more and more often for diagnosis, for monitoring the treatment and its results. Stomatology may use MRI for oncological and traumatological diagnoses or in case of genetic malformations of the maxillofacial region. The behaviour of metal objects in the orofacial region in the magnetic fields of an MR device is of interest to dentists and radiologists who use MRI. Head and neck MRI is of interest not only to dentists but also to other medical specialists who are interested in this area. The aim of this study is to evaluate the behaviour of selected dental alloys and metallic dental objects in the MR device and to estimate the potential health risk for patients undergoing an MR examination. The results will be formulated as a medical recommendation, classifying the dental alloys tested according to their MR compatibility as (1) acceptable, (2) unsuitable, (3) contraindicated in MR. Specific tasks of ISI: Physical-theoretical background for the project: - analysis of the interaction of the metallic object with the magnetic fields of the MR instrument (static field, switched gradient fields, radiofrequency field), - analysis of safety-relevant implications of the interaction, - analysis of MR artefacts with respect to specific measurement methods, correction possibilities, applicability to material assessment, - development of calculation methods and tools for the evaluation of the interaction (computer simulation of magnetic fields) and their consequences (forces, heating, artifacts), - development of experiments and calculation procedures for the determination of the required material parameters including their reliability assessment. Experimental background for the project: - experiments for the verification of theory, simulation and analytical calculation tools, - optimization of experiments and phantoms for the measurement of the tested materials, - measurement of about 100 materials according the the prepared protocol, - data analysis (determination of material parameters, simulations, material classification). |
