Self-ion bombardment of pure tungsten with ion energies of 2 MeV is used to mimic the defects created by neutrons in a fusion reactor. Electron microscopy is used to characterize the microstructure of samples. Thermal Desorption Spectrometry (TDS) is performed on deuterium implanted samples in order to estimate deuterium inventory as function of damage and compare with previous results. A Positron Annihilation Spectroscopy (PAS) study of self-irradiated but not implanted samples allows to study density of irradiation defects as function of damage and saturation of the density at doses between 0.1 and 0.5 displacements per atom (dpa) is found. These results are discussed in relation to recent theoretical estimates for defect saturation.