Nuclear medicine

This article presents a brief history of nuclear medicine in France and describes the recent developments and equipment of the 3 techniques most used in hospital nuclear departments: 1) gamma-camera, 2) single photon emission computed tomography (SPECT), and 3) positron emission computed tomography (PECT). Concerning gamma-camera, a new design is being studied in a collaboration between the Saint-Gobain company and the LETI (a laboratory of Cea). In this innovative design the scintillator and the photomultiplier are replaced by a matrix of semi-conductor detectors based on CdZnTe crystal combined with an adequate electronic equipment. Concerning SPECT, many different techniques and equipment are used. Most improvements handle with the reduction of the survey time for the patient by using several detectors set on a ring around the patient. Concerning PECT, the developments follow 2 parallel ways: first the use of better scintillating materials for detecting 511 KeV photons (BGO: bismuth germanate, BaF2, LSO: lutetium orthosilicate, or GSO: gadolinium orthosilicate), and secondly the use of beta+ decay radionuclides that are more easily integrated in molecules similar to those present in the humane metabolism (18F through the fluorodeoxyglucose molecule). (A.C.)