This invention relates to a high resolution and low dosage tomographic imaging in three dimensions, and more particularly, to a fully analytical fast iterative statistical algorithm for image reconstruction from projections obtained in a spiral cone-beam x-ray scanner is described. The presented method allows to improve the resolution of the reconstructed images and/or to decrease the x-ray intensity while maintaining the quality of the obtained CT images, because the signals obtained are adapted to the specific statistics for this imaging technique. The location of pixels in a reconstructed image and the location of detectors in a detector array in this new approach are described. The topology of pixels and detectors presented here avoids an inconsistency in the distribution of the coefficients assigned to the pixels in the image, which appears in the formulation of the analytical iterative statistical reconstruction problem.