We have developed an image quality theory for reconstruction that we apply to filtered back-projection (FBP) and statistical reconstruction (OSEM) for Single Photon Emission Computed Tomography (SPECT). Quantitative measures of reconstruction performance are given in terms of signal and noise power spectra, SPS and NPS, that we derive from phantom images. This allows evaluating the properties o...

3.3 Multi-slice CT Acquisition and Reconstruction for Body Imaging 52 3.3.1 Defi nition of the Pitch 52 3.3.2 The Cone-Angle Problem in Multi-slice CT 53 3.3.3 Multi-slice Spiral Reconstruction Neglecting the Cone-Beam Geometry 54 3.3.3.1 180° and 360° Multi-slice Linear Interpolation 54 3.3.3.2 z-Filter Approaches 56 3.3.4 Multi-slice Spiral Reconstruction with Cone-Beam Algorithms 58 3.3.4.1 ...

Abstract. We establish inversion formulas of the so called filtered back-projection type to recover a function supported in the ball in even dimensions from its spherical means over spheres centered on the boundary of the ball. We also find several formulas to recover initial data of the form (f, 0) (or (0, g)) for the free space wave equation in even dimensions from the trace of the solution o...

For all their diagnostic value, computed tomography (CT) examinations have relatively high radiation exposure. Past efforts to decrease patient dose emphasized advances in data acquisition technology because attempts to decrease dose resulted in increased image noise from filtered back projection reconstruction techniques. Iterative reconstruction techniques lead to reduced dose and maintain im...

Objective – Classically, the missing portions in the oblique projection data acquired from cylindrical scanners are synthesized by forward projecting an estimation of the activity computed from non-oblique data. Another quick and powerful way to perform the estimation of the truncated portions consists in applying Fourier rebinning methods. This paper intends to compare the performances of 3D g...

We present a development of the beam-tracking approach that allows its implementation in computed tomography. One absorbing mask placed before the sample and a high resolution detector are used to track variations in the beam intensity distribution caused by the sample. Absorption, refraction, and dark-field are retrieved through a multi-Gaussian interpolation of the beam. Standard filtered bac...

We have developed an image quality theory for reconstruction that we apply to filtered back-projection (FBP) and statistical reconstruction (OSEM) for Single Photon Emission Computed Tomography (SPECT). Quantitative measures of reconstruction performance are given in terms of signal and noise power spectra, SPS and NPS, that we derive from phantom images. This allows evaluating the properties o...