The evolution of medical imaging: from Geiger counters to MRI--a personal saga.

This article traces the evolution of medical imaging, from the crude images of the thyroid gland obtained using Geiger and scintillation counters, to the automatic scanners built to image brain tumors and organs, to gamma cameras, to digital imaging. A computed tomography scanner built in Aberdeen in the late 1960s led to the present-day gamma-camera tomographs, the main workhorse of nuclear medicine. The gradual evolution of the steps needed for clinical magnetic resonance imaging (MRI) are described, along with the rapid development of this novel form of body imaging. A brief account is also given of the present-day use of MRI in clinical medicine worldwide, with some modern cutting-edge applications, and its possible future.