We investigated the performances of two computed tomography (CT) systems produced by the same manufacturers (Somatom Flash and Edge Siemens) with different detector technologies (Ultrafast Ceramic and Stellar) and different generation of iterative reconstruction (IR) algorithms (SAFIRE and ADMIRE). A homemade phantom was scanned and the images were reconstructed with filtered back-projection (FBP) and IR algorithms. In terms of image quality, the performances of the systems were checked using the low-contrast detectability, evaluated by a Channelized Hotelling Observer (CHO), and the noise power spectrum (NPS). The analysis with CHO showed the best performance of Edge respect to Flash system for both FBP and IR algorithms. This better behavior, which reaches 20%, has been ascribed to the Stellar detector. From the NPS analysis, the noise reduction due to Stellar detector was 57%, moreover ADMIRE algorithm preserves a more traditional CT image texture appearance versus SAFIRE due to a lower NPS peak shift.

Download full-text PDF

Source
http://dx.doi.org/10.1093/rpd/ncaa034DOI Listing

Publication Analysis

Top Keywords

channelized hotelling
8
hotelling observer
8
fbp algorithms
8
nps analysis
8
stellar detector
8
characterization systems
4
systems channelized
4
nps
4
observer nps
4
nps metric
4

Similar Publications

Statistical biases correction in channelized Hotelling model observers.

Phys Med Biol

December 2024

GE HealthCare, Interventional X-ray Image Quality Engineering, Buc, France.

Article Synopsis
  • Channelized Hotelling observers (CHO) effectively simulate human visual performance in medical imaging detection tasks, but they can be skewed by statistical biases related to zero-signal scenarios and small sample sizes.
  • A method to correct these biases and the asymmetry of confidence intervals (CIs) was investigated, using simulations with various image sizes and noise levels.
  • The use of median values proved effective for accurate correction, especially at low signal levels, and yielded results that closely matched extrapolated values, thus providing a reliable adjustment for CHO biases.
View Article and Find Full Text PDF

Myocardial perfusion imaging using single-photon emission computed tomography (SPECT), or myocardial perfusion SPECT (MPS) is a widely used clinical imaging modality for the diagnosis of coronary artery disease. Current clinical protocols for acquiring and reconstructing MPS images are similar for most patients. However, for patients with outlier anatomical characteristics, such as large breasts, images acquired using conventional protocols are often sub-optimal in quality, leading to degraded diagnostic accuracy.

View Article and Find Full Text PDF

Dual-Split CT to Simulate Multiple Radiation Doses From a Single Scan-Liver Lesion Detection Compared With Dose-Matched Single-Energy CT.

Invest Radiol

February 2025

From the Institute of Radiation Physics, University Hospital Lausanne (CHUV), University of Lausanne, Lausanne, Switzerland (D.R., L.G.M., A.V.); Department of Radiology, Kantonsspital Baden, Affiliated Hospital for Research and Teaching of the Faculty of Medicine of the University of Zurich, Baden, Switzerland (T.N., R.A.K.-H., A.E.); Department of Biomedical Imaging and Image-Guided Therapy, Division of Neuroradiology and Musculoskeletal Radiology, Medical University of Vienna, Vienna, Austria (B.N.); and Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (H.A., T.F.).

Objectives: The aim of this study was to evaluate the potential use of simulated radiation doses from a dual-split CT scan for dose optimization by comparing their lesion detectability to dose-matched single-energy CT acquisitions at different radiation dose levels using a mathematical model observer.

Materials And Methods: An anthropomorphic abdominal phantom with liver lesions (5-10 mm, both hyperattenuating and hypoattenuating) was imaged using a third-generation dual-source CT in single-energy dual-source mode at 100 kVp and 3 radiation doses (5, 2.5, 1.

View Article and Find Full Text PDF

Background: Lesion detection is one of the most important clinical tasks in positron emission tomography (PET) for oncology. An anthropomorphic model observer (MO) designed to replicate human observers (HOs) in a detection task is an important tool for assessing task-based image quality. The channelized Hotelling observer (CHO) has been the most popular anthropomorphic MO.

View Article and Find Full Text PDF

Purpose: We aim to compare the low-contrast detectability of a clinical whole-body photon-counting-detector (PCD)-CT at different scan modes and image types with an energy-integrating-detector (EID)-CT.

Approach: We used a channelized Hotelling observer (CHO) previously optimized for quality control purposes. An American College of Radiology CT accreditation phantom was scanned on both PCD-CT and EID-CT with 10 phantom positionings.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!