OBJECTIVE To evaluate the image quality and diagnostic accuracy of very low-dose computed tomography (CT) angiography (CTA) for the evaluation of coronary artery stenosis. BACKGROUND Iterative reconstruction (IR) has shown to substantially reduce image noise and hence permit the use of very low-dose data acquisition protocols in coronary CTA. METHODS Fifty symptomatic patients with an inter...

AIM To assess quality and radiologists' preference of low-dose computed tomography (LDCT) reconstructed with filtered back projection (FBP) or Iterative Reconstruction. METHODS Thin-section LDCTs (1-mm thick contiguous images; 120 kVp; 30 mAs) of 38 consecutive unselected patients, evaluated for various clinical indications, were reconstructed by four different reconstruction algorithms: FBP ...

PURPOSE To compare the dose and image quality of a standard dose abdominal and pelvic CT with Filtered Back Projection (FBP) to low-dose CT with Adaptive Iterative Dose Reduction 3D (AIDR 3D). MATERIALS AND METHODS We retrospectively examined the images of 21 patients in the portal phase of an abdominal and pelvic CT scan before and after implementation of AIDR 3D iterative reconstruction. Th...

PURPOSE To assess image quality of CT pulmonary angiography (CTPA) at reduced radiation exposure (RD-CTPA) and contrast medium (CM) volume using two different iterative reconstruction (IR) algorithms (iDose4 and iterative model reconstruction (IMR)) in comparison to filtered back projection (FBP). MATERIALS AND METHODS 52 patients (body weight < 100 kg, mean BMI: 23.9) with suspected pulmonar...

This paper presents improved autoregressive modelling (AR) to reduce noise in SPECT images. An AR filter was applied to prefilter projection images and postfilter ordered subset expectation maximisation (OSEM) reconstruction images (AR-OSEM-AR method). The performance of this method was compared with filtered back projection (FBP) preceded by Butterworth filtering (BW-FBP method) and the OSEM r...

BACKGROUND: Positron emission tomography (PET) is a powerful imaging technique with the potential of obtaining functional or biochemical information by measuring distribution and kinetics of radiolabelled molecules in a biological system, both in vitro and in vivo. PET images can be used directly or after kinetic modelling to extract quantitative values of a desired physiological, biochemical o...

Purpose: Nonstationarity of CT noise presents a major challenge to the assessment of image quality. This work presents models for imaging performance in both filtered backprojection (FBP) and penalized likelihood (PL) reconstruction that describe not only the dependence on the imaging chain but also the dependence on the object as well as the nonstationary characteristics of the signal and nois...

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....

We quantitatively compare filtered backprojection (FBP), expectation maximization (EM), and Bayesian reconstruction algorithms as applied to the IndyPET scanner a dedicated research scanner which has been developed for small and intermediate field of view imaging applications. In contrast to previous approaches that rely on Monte Carlo simulations, a key feature of our investigation is the use ...

Abstract Background Q.Clear is a Bayesian penalized likelihood (BPL) reconstruction algorithm that presents improvements in signal-to-noise ratio (SNR) clinical positron emission tomography (PET) scans. Brain studies research require provides good spatial resolution and accentuates contrast features however, filtered back-projection (FBP) not available on GE SIGNA PET-Magnetic Resonance (PET-MR...