AI Article Synopsis
Article Abstract
X-ray tubes for medical applications typically generate x-rays by accelerating electrons, emitted from a cathode, with an interelectrode electric field, towards an anode target. X-rays are not emitted from one point, but from an irregularly shaped area on the anode, the focal spot. Focal spot intensity distributions and off-focal radiation negatively affect the imaging spatial resolution and broadens the beam penumbra. In this study, a Monte Carlo simulation model of an x-ray tube was developed to evaluate the spectral and spatial characteristics of off-focal radiation for multiple photon energies. Slit camera measurements were used to determine the horizontal and vertical intensity profiles of the small and the large focal spot of a diagnostic x-ray tube. First, electron beamlet weighting factors were obtained via an iterative optimization method to represent both focal spot sizes. These weighting factors were then used to extract off-focal spot radiation characteristics for the small and large focal spot sizes at 80, 100, and 120 kV. Finally, 120 kV simulations of a steel sphere (d = 4 mm) were performed to investigate image blurring with a point source, the small focal spot, and the large focal spot. The magnitude of off-focal radiation strongly depends on the anode size and the electric field coverage, and only minimally on the tube potential and the primary focal spot size. In conclusion, an x-ray tube Monte Carlo simulation model was developed to simulate focal spot intensity distributions and to evaluate off-focal radiation characteristics at several energies. This model can be further employed to investigate focal spot correction methods and to improve cone-beam CT image quality.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1088/1361-6560/ab6178 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Molecular basis of resistance to leaf spot disease in oil palm.
Front Plant Sci
December 2024
School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom.
Introduction: Leaf spot disease caused by the fungal pathogen is one of the most common diseases found in oil palm () nurseries in South East Asia, and is most prevalent at the seedling stage. Severe infections result in localized necrotic regions of leaves that rapidly spread within nurseries leading to poor quality seedlings and high economic losses.
Methods: To understand the molecular mechanisms of this plant-pathogen interaction, RNA-Seq was used to elucidate the transcriptomes of three oil palm genotypes with contrasting pathogen responses (G10 and G12, resistant and G14, susceptible) following infection with spores.
An enhanced classification system of various rice plant diseases based on multi-level handcrafted feature extraction technique.
Sci Rep
December 2024
Information Technology Department, Faculty of Computers and Information, Mansoura University, Mansoura, 35516, Egypt.
The rice plant is one of the most significant crops in the world, and it suffers from various diseases. The traditional methods for rice disease detection are complex and time-consuming, mainly depending on the expert's experience. The explosive growth in image processing, computer vision, and deep learning techniques provides effective and innovative agriculture solutions for automatically detecting and classifying these diseases.
View Article and Find Full Text PDFOn the origin of MTF reduction in grating-based x-ray differential phase contrast CT imaging.
Med Phys
December 2024
Research Center for Advanced Detection Materials and Medical Imaging Devices, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China.
Background: The complementary absorption contrast CT (ACT) and differential phase contrast CT (DPCT) can be generated simultaneously from an x-ray computed tomography (CT) imaging system incorporated with grating interferometer. However, it has been reported that ACT images exhibit better spatial resolution than DPCT images. By far, the primary cause of such discrepancy remains unclear.
View Article and Find Full Text PDFDigital breast tomosynthesis system concept addressing the needs in breast cancer screening and diagnosis.
J Med Imaging (Bellingham)
January 2025
Siemens Healthineers AG, Forchheim, Germany.
Purpose: Digital breast tomosynthesis (DBT) has been introduced more than a decade ago. Studies have shown higher breast cancer detection rates and lower recall rates, and it has become an established imaging method in diagnostic settings. However, full-field digital mammography (FFDM) remains the most common imaging modality for screening in many countries, as it delivers high-resolution planar images of the breast.
View Article and Find Full Text PDFLeopard spot retinopathy represents the initial sign of rhegmatogenous retinal detachment in children: a report of two cases.
BMC Ophthalmol
December 2024
Department of Ophthalmology, The Second Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei Province, China.
Background: Leopard spots can appear in a variety of diseases; however, they are extremely rare in children with rhegmatogenous retinal detachment. This study presents two such rare cases in which leopard spot retinopathy was the initial manifestation of rhegmatogenous retinal detachment.
Case Presentation: Case 1 involved a 4-year-old boy had previously been diagnosed with left eye uveitis and received systemic steroid therapy at a local hospital, but symptoms persisted.
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!