Magnetic resonance imaging (MRI) is a computerized method of depicting the morphology of anatomic structures in cross-section. The basic principles of this technique were discovered by two American physicists, Felix Bloch and Edward Purcell, in 1946, who were subsequently awarded the Nobel Prize in Physics in 1952 for their work. The difficulties inherent in developing the necessary technology to construct the large magnets with excellent field uniformity delayed the clinical application of MRI until 1979.