The accurate and rapid location of the radionuclide distribution in radioactively labeled tissue or organs is the goal of nuclear medicine. The Compton camera, in principle, can improve the spatial resolution and effiency with respect to today's PET and SPECT techniques. Since it is necessary to reconstruct a full scattering event in the Compton camera, the detector technology is very demanding. Useful detectors have not been available in the past. However, a new detector type, the Silicon Drift Detector (SDD), developed
for experiments in x-ray astrophysics show promising features. The test of such a system is the main objective of this thesis.
The optimization of a Compton camera system in terms of effiency and resolution
is a complex multiparameter problem which depends on various detector properties. The influence of these parameters on the performance of the Compton camera system is investigated in this work using the analytical system models and Monte Carlo simulations in order to find optimum detector parameters.
Compton camera test setup has been constructed using a 19 channel SDD with onchip JFET as the scatter detector and an Anger camera without a lead collimator as the absorption detector. The equivalent noise charge of the SDD channels at 10 °C with a shaping time of 100 ns was measured to be between 30-40 electrons rms. New readout scheme has been implemented for the fast readout of the detector which is crucial for this application. The system is designed such that the measurements can be done in all detector orientations and kinematical conditions.
Compton camera coincidence events with high statistics have been acquired by irradiating the SDD cells with a finely-collimated 1 Ci 137 Cs source. Time, energy and angular distributions of coincidence events measured with this detector system are presented in this work. It is shown that with the scatter detector having an excellent energy resolution, it is possible to reconstruct the source distribution accurately using the locations of the interactions measured in two detectors.