Investigation of the radiation dose in computed micro tomography using the Medipix3 semiconductor detector in combination with an iterative reconstruction algorithm

Due to the acquisition of up to two thousand projections, the radiation dose during computed tomography scans is severely higher, compared to planar radiographic imaging. Especially in medical diagnostics the minimization of the radiation dose a patient is exposed to, is of fundamental interest to reduce the appearance of radiation-induced damage. The use of photon-counting semiconductor detectors, like the Medipix3, in combination with iterative reconstruction algorithms, provides a possibility to achieve this objective. Therefore, measurements on phantoms are performed to determine the minimum amount of projections needed for the iterative reconstruction to work without the loss of spatial resolution and image contrast. We will show that it is possible to reduce the radiation dose necessary for computed tomography (CT) scans which will be a significant time saver and lower the cost of CT concerning material analysis. Regarding medical diagnostics, the reduction of the radiation dose can lead to a diminishing in the appearance of radiation-induced damages.