The principles of NMR imaging and a review of early clinical results.

NMR imaging represents an exciting new development in the field of medicine. In this paper the physical principles of nuclear magnetic resonance imaging are reviewed. In addition the role of the major contrast determinants T1 and T2 relaxation times, proton density and blood flow are discussed. With NMR proton imaging high quality anatomic images may be obtained in the coronal, sagittal or cross axial plane. NMR appears to be a useful modality in the diagnosis of neurologic disease particularly in the posterior fossa or brainstem. Thoracic imaging appears promising due to the high contrast in the mediastinum between structures and mediastinal fat. A wide range of abdominal diseases may also be identified on NMR images. The potential advantages of imaging at higher magnetic field strengths are considered. These include improved spatial resolution and decreased scan times for some pulse sequences.