Toward proton computed tomography

Conventional 3D imaging of structures in medicine, biology and material science is done with computed tomography (CT), which relies on differential absorption of X-rays in materials depending on the atomic number. A potential alternative is the use of charged particles like protons, which can provide an image based on the specific energy loss and thus a density map of the traversed tissues. The proton CT (pCT) approach would provide superior reliability in radiation treatment planning at proton treatment center. Potentially, it could lead to a reduced radiation dose to the patient. We present initial results from a pCT feasibility study, which is based on proton transmission measurements on simple phantoms, taken with a telescope of silicon detectors with very high spatial and good energy resolution.