The dramatic evolution of new technology in diagnostic and therapeutic radiology has changed the whole field of medicine. Ultrasonography, computed tomography, nuclear magnetic resonance, and digital radiography are those new techniques which are undergoing continuous development, providing us with increasingly re fined methods for establishing the cause of disease and for treating the patient. Using radiologic technique, ingenious methods are continuously being developed to en sure less expensive, less traumatic, and more efficient therapy. Transluminal angio plasty, embolization of tumors or bleeding vessels, extraction or dissolution of stones, and regional infusions are some of these therapeutic methods in modem diagnostic radiology. Every day new ideas arise which are published in a multitude of papers. This heavy flow of information limits the possibility of selecting from a core of information and often prevents radiologists from communicating efficiently with their colleagues in other countries or continents. European radiologists are additionally hampered from participating in international communication because of the language barriers created by the national journals. As a result, Europe's contribution to scientific progress in this interdisciplinary field has influenced only regional developments."

This book is a supplement to Volume V/I in the present series, Diag- nostie Radiology, published in 1962. Despite the relatively long period of time whieh has elapsed sinee its publieation, that eomprehensive vol- urne is still essentially valid, even though further developments have of course oeeurred in eertain fields. In reeent years the developments in nuclear medieine and ultrasonie teehniques have led to a number of new methods of medieal investigation, whieh, in different ways, eomplement diagnostie radiology. Funetional disorders of the urinary traet ean often be detected by means of radioiso- topes. Sinee morphologie ehanges are almost always preeeeded by fune- tional disturbanees, radionuclide teehniques in many instanees produee an earlier diagnosis than radiography. Disturbances of renal blood flow, slight ureterie obstruetion, and ureterie reflux are examples of pathologie states whieh ean be deteeted early by the y scintillation eamera. Bone seans, Le., imaging of the skeletal system using a radionuclide, are used extensively to diagnose bone metastases now that it has been demonstrated that such metastatie growths are identified both earlier and with greater aeeuraey by scintigraphy than by radiographie teeh- niques.