Heavy ion CT reconstructed from range shift distribution measured by 2D detection system

An algorithm for heavy ion CT reconstruction from residual range measurement data is presented. The experimental procedure is described, in which an intensifying screen and a TV camera with a micro-channel-plate intensifier were used for the detection of energy deposition profile for the heavy ion ¹²C with an initial energy of 400 MeV/u emitted from a HIMAC. A series of projection images of a water phantom with PMMA pipes were experimentally taken for various values of range shifter thickness at each projection angle. From these images the distribution of residual range was obtained and used for reconstruction of the relative stopping power. The spatial resolution of the system was estimated as less than 2 mm