[The history of tomography]

It is easily forgotten that not yet a hundred years ago the only way to look into the patients' body was via invasive procedures. Within the year of the discovery of X-rays by Conrad Röntgen the need for three dimensional imaging had been voiced. The driving force behind this development was undoubtedly clinical motivation. Planar X-radiographs were not satisfactory to the clinicians who urged the radiologists to provide them with tomographic images. Between 1910 and 1940, classical tomography has been the product of individuals rather than collective groups. It is only in the mid thirties that scientists found out about each other and started to correspond vigorously. Mayer was the first to suggest in 1914 the idea of tomography. Bocage, Grossman and Vallebona all developed the idea further and built their own equipment. In 1931 Ziedses des Plantes published the most extensive and thorough study on tomography. In the forties and fifties a stagnation is noticed, only further refinements to the existing equipment are carried out. Although Frank and Takahashi published the basic principles of axial tomography in the mid forties, we had to wait for the necessary developments in electronics before Hounsfield was able to develop and commercialize the first axial computer tomography in 1972 (EMI-Scanner). At the time all the big radiology companies rushed into the field and soon, second, third and fourth generation CT scanners became available. Only a few years later a new way of generating images without using ionizing radiation was introduced. Lauterbur and Damadian produced the first low quality images with magnetic resonance, a technique called zeugmatography by its inventors. In 1974 the first images of a living subject were published and initial scepticism was replaced by euphoria. This resulted in the spectacular evolution in Magnetic Resonance that we are now observing. While it is impossible to predict the future, the development of networks, the increase in data acquisition and storage will spread a new light on our specialty. A closer cooperation between radiologists, pathologists and clinicians will undoubtedly be necessary, as well as a partial redefinition of the radiologists task.