High energy photons and electrons: new surgical instruments

The implications of ionizing radiations to medicine are well known, both for diagnostics and therapy. Their development for Radiotherapy has been constrained during the first part of our century to x-rays up to energy levels of 400 KV and natural radioisotopes like Ra. The author makes a historical review of different radiological procedures and provides information about their application into medicine, with special emphasis on computerized tomography, ultrasounds and Nuclear Magnetic Resonance (NMR)