Objective(s): In SPECT, the sinogram contains scatter and lack of attenuated counts that degrade the reconstructed image quality and quantity. Many techniques for attenuation and scatter correction have been proposed. An acceptable method of correction is to incorporate effects into an iterative statistical reconstruction. Here, we propose new Maximum Likelihood Expectation Maximiz...

OBJECTIVE To step-wise evaluate image quality of sinogram-affirmed iterative reconstruction (SAFIRE) in reduced-dose (RD) thoracoabdominal computed tomography (CT) compared to full-dose (FD) and RD filtered back projection (FBP) in a longitudinal study. MATERIALS AND METHODS 122 patients were included in this prospective study. 49 patients (14 men: mean age ± SD, 56±0.4 years; 35 women: 58±1....

PURPOSE To compare the image quality and diagnostic accuracy between sinogram affirmed iterative reconstruction (SAFIRE) algorithm and filtered back projection (FBP) reconstruction algorithm at 70 kVp-tube-voltage DSCT angiography in children with congenital heart disease (CHD). MATERIALS AND METHODS Twenty-eight patients (mean age: 13 months; range: 2-48 months; male: 16; female: 12; mean we...

Department of Physics of Molecular Imaging Systems, Institute for Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany Despite promising advances, attenuation correction of PET data remains challenging in PET/MRI. Known approaches to estimating attenuation maps from PET emission data take into account only true coincidences and fail to completely determine the attenuation map...

Purpose: The aim of this study is to evaluate the impact of different scatter correction strategies on quantification of high-resolution research tomograph (HRRT) data for three tracers covering a wide range in kinetic profiles. Procedures: Healthy subjects received dynamic HRRT scans using either (R)-[C]verapamil (n=5), [C]raclopride (n=5) or [C]flumazenil (n=5). To reduce the effects of patie...

In this paper, we suggest a new method for verifying the motion of a binary multileaf collimator (MLC) in helical tomotherapy. For this we used a combination of a cylindrical scintillator and a general-purpose camcorder. The camcorder records the light from the scintillator following photon irradiation, which we use to track the motion of the binary MLC. The purpose of this study is to demonstr...

In dynamic Positron Emission Tomography (PET), an estimate of the radio activity concentration is obtained from a series of frames of sinogram data taken at ranging in duration from 10 seconds to minutes under some criteria. So far, all the well-known reconstruction algorithms require known data statistical properties. It limits the speed of data acquisition, besides, it is unable to afford the...

objective(s): in spect, the sinogram contains scatter and lack of attenuated counts that degrade the reconstructed image quality and quantity. many techniques for attenuation and scatter correction have been proposed. an acceptable method of correction is to incorporate effects into an iterative statistical reconstruction. here, we propose new maximum likelihood expectation maximization (mlem) ...

This paper introduces two novel strategies for iterative reconstruction of full interior tomography (FINT) data, i.e. when the field of view is entirely inside the object support and knowledge of the object support itself or the attenuation coefficients inside specific regions of interest are not available. The first approach is based on data edge-padding. The second technique creates an interm...

BACKGROUND AND PURPOSE CT is a ubiquitous, efficient, and cost-effective method to evaluate pediatric ventricular size, particularly in patients with CSF shunt diversion who often need emergent imaging. We therefore sought to determine the minimum dose output or CT dose index required to produce clinically acceptable examinations. MATERIALS AND METHODS Using a validated noise insertion method...