The influence of different physical parameters, such as the source size and the energy spectrum, on the functional capability of a grating interferometer applied for phase-contrast imaging is discussed using numerical simulations based on Fresnel diffraction theory. The presented simulation results explain why the interferometer could be well combined with polychromatic laboratory x-ray sources in recent experiments. Furthermore, it is shown that the distance between the two gratings of the interferometer is not in general limited by the width of the photon energy spectrum. This implies that interferometers that give a further improved image quality for phase measurements can be designed, because the primary measurement signal for phase measurements can be increased by enlargement of this distance. Finally, the mathematical background and practical instructions for the quantitative evaluation of measurement data acquired with a polychromatic x-ray source are given.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/j.1365-2818.2008.02072.x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Transmantle pressure under the influence of free breathing: non-invasive quantification of the aqueduct pressure gradient in healthy adults.
Fluids Barriers CNS
January 2025
Medical Image Processing Department, CHU Amiens-Picardie University Hospital, Amiens, France.
Background: The pressure gradient between the ventricles and the subarachnoid space (transmantle pressure) is crucial for understanding CSF circulation and the pathogenesis of certain neurodegenerative diseases. This pressure can be approximated by the pressure difference across the aqueduct (ΔP). Currently, no dedicated platform exists for quantifying ΔP, and no research has been conducted on the impact of breathing on ΔP.
View Article and Find Full Text PDFPredicting the Invasiveness of Mixed Ground-Glass Nodules Based on Spectral Computed Tomography-Derived Parameters and Tumor Abnormal Protein Levels: Development and Validation of a Model.
Acad Radiol
January 2025
Department of Radiology, Shengjing Hospital of China Medical University, China (Y.Y., T.W.). Electronic address:
Rationale And Objectives: Mixed ground-glass nodules (mGGNs) are highly malignant and common nonspecific lung imaging findings. This study aimed to explore whether combining quantitative and qualitative spectral dual-layer detector-based computed tomography (SDCT)-derived parameters with serological tumor abnormal proteins (TAPs) and thymidine kinase 1 (TK1) expression enhances invasive mGGN diagnostic efficacy and to develop a joint diagnostic model.
Materials And Methods: This prospective study included patients with mGGNs undergoing preoperative triple-phase contrast-enhanced SDCT with TAP and TK1 tests.
Identifying non-responders to cardiac resynchronization therapy in the non-left bundle branch block.
J Interv Card Electrophysiol
January 2025
Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, 6-1 Kishibe-Shimmachi, Suita, Osaka, 564-8565, Japan.
Background: Non-response to cardiac resynchronization therapy (CRT) is an important issue in the treatment of heart failure with reduced ejection fraction (HFrEF) and non-left bundle branch block (LBBB). Electrocardiogram-gated myocardial perfusion single-photon emission computed tomography imaging (G-MPI SPECT) is typically used to assess left ventricular (LV) dyssynchrony. This study aimed to determine whether G-MPI parameters are associated with non-responsiveness to CRT.
View Article and Find Full Text PDFBasic Science and Pathogenesis.
Alzheimers Dement
December 2024
Department of Radiology, miami, FL, USA.
Background: Clearance of brain toxins occurs during sleep, although the mechanism remains unknown. Previous studies implied that the intracranial aqueductal cerebrospinal fluid (CSF) oscillations are involved, but no mechanism was suggested. The rationale for focusing on the aqueductal CSF oscillations is unclear.
View Article and Find Full Text PDFBasic Science and Pathogenesis.
Alzheimers Dement
December 2024
Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA.
Background: Cognitive decline is often influenced by Alzheimer's disease (AD) pathology (e.g., beta-amyloid burden) and other pathology (e.
View Article and Find Full Text PDFWant 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!