In the past two decades the nature of radiology has changed almost beyond recognition. The fundamental nature of this change is reflected in the increasing use of the term ‘imaging’ to encompass all those activities that now lie within the ambit of the radiologist and to which the somewhat restrictive term ‘radiology’ seems ever more inappropriate.

The continuing burgeoning in the number and variety of imaging methods available to us has been engendered in no small part by the technological advances that have taken place in physics, electronics, engineering, the structural and material sciences and, of course, computer science; these advances have not only improved existing techniques beyond recognition, but have also actually spawned entirely new modalities of investigation. It is no exaggeration to say that the changes that the application of these new modalities have wrought have revolutionized the practice of medicine in terms of both the diagnosis and subsequent management of patients. One consequence of these changes, however, is the perplexing array of imaging sub-specialities that now exists and which creates problems for the young and old radiologist alike. The former has to get to grips with the fundamental principles of not just one or two but a dozen imaging modalities, learn their appropriate applications in a diagnostically effective, safe and economic manner, and learn a variety of interventional techniques that are little different in their complexity and potential risk from what was formerly a large tranche of conventional surgery.