The physical performances of a single slice positron tomographic system and preliminary results in a clinical environment.

Metabolic phenomena can be studied and measured non-invasively using positron emitting radionuclides and a suitably adapted tomographic system. The choice of a single slice ring camera is justified by its physical performance, which is presented here and discussed. A series of measurements with geometrical phantoms and analytical simulations have been performed to determine the critical characteristics of the system. This has permitted optimization of certain parameters enabling very interesting clinical results to be obtained at SHFJ, particularly in the area of cerebral physiopathology. In addition, the potential of obtaining absolute quantitative values of regional activity is presented. The calibration of the regional activity is presented. The calibration of the system, spatial non-stationarities, and attenuation correction, which represent the main sources of error, are considered in detail. A precision of the order of 10% should be obtainable. Such a quantitation method has been successfully applied to the in vivo study of the regional extraction of cerebral oxygen.