In this study related to human brain SPECT imaging, simulation of half-cone-beam (HCB) collimation with different scan paths is performed and compared with simulated fan-beam and parallel-hole circular orbit acquisitions of disk-phantom projection data. Acquisition types are quantitatively evaluated based on the photon detection efficiency, the root-mean-squared error, contrast and signal-to-noise ratio measurements of the reconstructed images. We demonstrate that a triple-camera SPECT system with half-cone-beam collimators and circle-and-helix scan paths can offer up to a 26% efficiency increase over fan-beam, and up to a 128% increase over parallel-hole collimators for equal spatial resolutions, and display no visible axial sampling artifacts in reconstructed disk-phantom images. In addition, we perform qualitative experimental evaluation of triple-HCB circle-and-helix acquisition using a Hoffman 3D brain phantom. Reconstructed brain phantom images show improved quality due to reduced noise and no apparent sampling artifacts. Triple-HCB circle-and-helix SPECT has a potential for improved brain imaging, producing higher image quality with a smaller reconstruction error and better lesion detectability due to increased efficiency for equal spatial resolution compared to conventional fan-beam and parallel-hole SPECT.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2745161PMC
http://dx.doi.org/10.1109/TNS.2008.2003255DOI Listing

Publication Analysis

Top Keywords

scan paths
12
brain spect
8
fan-beam parallel-hole
8
equal spatial
8
sampling artifacts
8
triple-hcb circle-and-helix
8
brain phantom
8
brain
5
spect
5
quantitative evaluation
4

Similar Publications

Some large social environments are expected to use Covered Path Planning (CPP) methods to handle daily tasks such as cleaning and disinfection. These environments are usually large in scale, chaotic in structure, and contain many obstacles. The proposed method is based on the improved SCAN-STC (Spanning Tree Coverage) method and significantly reduces the solution time by optimizing the backtracking module of the algorithm.

View Article and Find Full Text PDF

LesionScanNet: dual-path convolutional neural network for acute appendicitis diagnosis.

Health Inf Sci Syst

December 2025

Section for Fisheries Technology, Institute of Aquatic Resources, DTU Aqua, Technical University of Denmark, 9850 Hirtshals, Denmark.

Acute appendicitis is an abrupt inflammation of the appendix, which causes symptoms such as abdominal pain, vomiting, and fever. Computed tomography (CT) is a useful tool in accurate diagnosis of acute appendicitis; however, it causes challenges due to factors such as the anatomical structure of the colon and localization of the appendix in CT images. In this paper, a novel Convolutional Neural Network model, namely, LesionScanNet for the computer-aided detection of acute appendicitis has been proposed.

View Article and Find Full Text PDF

Background: The search for rare elements, like mitotic figures, is crucial in pathology. Combining digital pathology with eye-tracking technology allows for the detailed study of how pathologists complete these important tasks.

Objectives: To determine if pathologists have distinct search characteristics in domain- and nondomain-specific tasks.

View Article and Find Full Text PDF

Integration of medicinal chemistry in therapeutic decision-making: A way forward?

Curr Pharm Teach Learn

November 2024

Teaching Emeritus, University of British Columbia, Faculty of Pharmaceutical Sciences, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada. Electronic address:

Many attempts have been made to integrate medicinal chemistry knowledge into therapeutic decision-making in pharmacy programs across North America. Examples include the use of Structure-Based Therapeutic Evaluations, alignment of medicinal chemistry content with courses in pharmacology, pharmaceutics and pharmacotherapeutics, and team-based or problem-based learning methods. The majority of these approaches indicate that students have greater confidence or comfort with medicinal chemistry, but there remain few cases where an improvement in performance has been measured.

View Article and Find Full Text PDF

Analyzing visual scan paths, the time-ordered sequence of eye fixations and saccades, can help us understand how operators visually search the environment before making a decision. To analyze and compare visual scan paths, prior studies have used metrics such as string edit similarity, which considers the order used to inspect areas of interest (AOIs), as well as metrics that consider the AOIs shared between visual scan paths. However, to identify similar visual scan paths, particularly in tasks and environments in which operators may apply variations of a common underlying visual scanning behavior, using solely one similarity metric might not be sufficient.

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!