MAGNETIC-FIELD STRENGTH ISSUES IN MAGNETIC-RESONANCE-IMAGING

The authors review the current status of magnetic resonance imaging (M RI) with respect to magnetic field strength. The discussion covers the practical aspects of MRI - safety, throughput and costs - as well as the clinical aspects as they are influenced by field strength. Data on the world distribution of MRI units of various field strengths are pr esented. Canada had the highest proportion of high-field units among t he 11 countries or regions included in this comparison, probably becau se most Canadian MRI units are located in teaching hospitals, where th ey are used for both research and clinical work.