We introduce a novel approach for compressive coding at the sensor layer for an integrated imaging system. Compression at the physical layer reduces the measurements-to-pixels ratio and the data volume for storage and transmission, without confounding image estimation or analysis. We introduce a particular compressive coding scheme based on the quantized Cosine transform (QCT) and the correspon...

PURPOSE To assess the noise characteristics of the new adaptive statistical iterative reconstruction (ASiR-V) in comparison to ASiR. METHODS A water phantom was acquired with common clinical scanning parameters, at five different levels of CTDIvol . Images were reconstructed with different kernels (STD, SOFT, and BONE), different IR levels (40%, 60%, and 100%) and different slice thickness (S...

Cone-beam computed tomography (CBCT) images suffer from poor image quality, in a large part due to contamination from scattered X-rays. In this work, a Monte Carlo (MC)-based iterative scatter correction algorithm was implemented on measured phantom data acquired from a clinical on-board CBCT scanner. An efficient EGSnrc user code (egs_cbct) was used to transport photons through an uncorrected ...

Statistical iterative image reconstruction methods are compute intensive. Fixed-point calculations can substantially reduce the computational load, but also increase quantization error. To investigate the effect of fixed-point quantization, we analyze the error propagation after introducing perturbation in a diagonally preconditioned gradient descent algorithm for X-ray computed tomography. The...

This paper intends to compare the abilities of the two major imaging modalities in nuclear medicine imaging: Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT). The motivations are many-fold: (i) To gain a better understanding of the strengths and limitations of the two imaging modalities in the context of recent and ongoing developments in hardware ...

conclusions modern cts with the innovative technology of a built-in tin filter allow for significant reduction of radiation exposure in patients with suspected urolithiasis by optimizing the x - ray spectrum with image quality as high as in standard ct devices results ct examinations of a total of 143 patients were assessed. dlp of force was 56% and 55% lower in comparison to as+ and flash, (74...

We propose a direct nonlinear reconstruction algorithm for Computed Tomography (CT), designed to handle low-dose measurements. It involves the filtered back-projection and adaptive nonlinear filtering in both the projection and the image domains. The filter is an extension of the learned shrinkage method by Hel-Or and Shaked to the case of indirect observations. The shrinkage functions are lear...

Grating-based phase-contrast computed tomography (PCCT) is a promising imaging tool on the horizon for pre-clinical and clinical applications. Until now PCCT has been plagued by strong artifacts when dense materials like bones are present. In this paper, we present a new statistical iterative reconstruction algorithm which overcomes this limitation. It makes use of the fact that an X-ray interf...