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The aim of the SCINTIRAD experiment is to determine the radio-response of 188Rhenium (Re) in in vitro cells and the biodistribution in different organs of in vivo mice, and subsequently to assess the therapeutic effect on liver tumours induced in mice. Both the γ- and β- emissions of 188Re have been exploited in the experiment. The in vivo biodistribution in mice was studied also with a γ-camera using different parallel hole collimators. In the 188Re spectrum, while the 155 keV γ-peak is useful for imaging, the photons emitted at larger energies and the β-particles act as noise in the image reconstruction. The γ-cameras previously used to image biodistributions obtained with 99Tc are, therefore, not optimized for use with 188Re. A new setup of the γ-camera has been studied for 188Re: 66×66 YAP:Ce crystals (0.6×0.6×10 mm3, 5 μm optical insulation) guarantee a FOV of 40×40 mm2, a Hamamatsu R2486 PSPMT, 3 in. diameter, converts their light into an electrical signal and allows reconstructing the spatial coordinates of the light spot; incoming photon directions are selected through a lead collimator with 1.5 mm diameter hexagonal holes, 0.18 mm septa, 40 mm thickness. Using this setup, results have been obtained both with 99Tc filled and 188Re filled capillaries and wells. The energy spectrum of the collected photons and the spatial resolutions obtainable with the 188Re source will be presented.