Purpose: To quantify the type, frequency, and magnitude of artifacts in four-dimensional (4D) CT images acquired using a multislice cine method.
Methods And Materials: Fifty consecutive patients who underwent 4D-CT scanning and radiotherapy for thoracic or abdominal cancers were included in this study. All the 4D-CT scans were performed on the GE multislice PET/CT scanner with the Varian Real-time Position Management system in cine mode. The GE Advantage 4D software was used to create 4D-CT data sets. The artifacts were then visually and quantitatively analyzed. We performed statistical analyses to evaluate the relationships between patient- or breathing-pattern-related parameters and the occurrence as well as magnitude of artifacts.
Results: It was found that 45 of 50 patients (90%) had at least one artifact (other than blurring) with a mean magnitude of 11.6 mm (range, 4.4-56.0 mm) in the diaphragm or heart. We also observed at least one artifact in 6 of 20 lung or mediastinal tumors (30%). Statistical analysis revealed that there were significant differences between several breathing-pattern-related parameters, including abdominal displacement (p < 0.01), for the subgroups of patients with and without artifacts. The magnitude of an artifact was found to be significantly but weakly correlated with the abdominal displacement difference between two adjacent couch positions (R = 0.34, p < 0.01).
Conclusions: This study has identified that the frequency and magnitude of artifacts in 4D-CT is alarmingly high. Significant improvement is needed in 4D-CT imaging.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2583232 | PMC |
| http://dx.doi.org/10.1016/j.ijrobp.2008.06.1937 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Investigating the effects of table movement and sag on optical surrogate-driven respiratory-guided computed tomography.
J Appl Clin Med Phys
November 2024
Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Universitätsstraße 27, Erlangen, Germany.
Purpose: Respiratory-guided computed tomography (CT) typically employs breathing motion surrogates to feed image reconstruction or visual breathing coaching. Our study aimed to assess the impact of table movements and table sag on the breathing curves recorded in four-dimensional (4D) CT and deep-inspiration breath-hold (DIBH) CT.
Methods: For breathing curve measurements, static and dynamic phantom scenarios were used.
Fast motion-compensated reconstruction for 4D-CBCT using deep learning-based groupwise registration.
Biomed Phys Eng Express
December 2024
Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, United States of America.
. Previous work has that deep learning (DL)-enhanced 4D cone beam computed tomography (4D-CBCT) images improve motion modeling and subsequent motion-compensated (MoCo) reconstruction for 4D-CBCT. However, building the motion model at treatment time via conventional deformable image registration (DIR) methods is not temporally feasible.
View Article and Find Full Text PDF4DCT image artifact detection using deep learning.
Med Phys
November 2024
Biomedical Engineering, University of Iowa, Iowa City, Iowa, USA.
Article Synopsis
- Four-dimensional computed tomography (4DCT) is crucial for radiation therapy but can suffer from motion artifacts that hinder accurate imaging.
- A deep learning algorithm using a U-net convolutional neural network was created to identify various artifact types in 4DCT images, trained on over 23,000 slices from 98 scans.
- The model outperformed previous methods with a sensitivity of 78%, specificity of 99%, and an ROC AUC of 0.99, showing it can effectively detect multiple artifacts in a single image.
Development of a novel 3D-printed dynamic anthropomorphic thorax phantom for evaluation of four-dimensional computed tomography.
Phys Imaging Radiat Oncol
October 2024
Department of Radiation Oncology (Maastro), GROW Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands.
Background And Purpose: In radiotherapy, the image quality of four-dimensional computed tomography (4DCT) is often degraded by artifacts resulting from breathing irregularities. Quality assurance mostly employ simplistic phantoms, not fully representing complexities and dynamics in patients. 3D-printing allows for design of highly customized phantoms.
View Article and Find Full Text PDFSuper-resolution reconstruction of time-resolved four-dimensional computed tomography (TR-4DCT) with multiple breathing cycles based on TR-4DMRI.
Med Phys
January 2025
Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA.
Background: Respiratory motion irregularities in lung cancer patients are common and can be severe during multi-fractional (∼20 mins/fraction) radiotherapy. However, the current clinical standard of motion management is to use a single-breath respiratory-correlated four-dimension computed tomography (RC-4DCT or 4DCT) to estimate tumor motion to delineate the internal tumor volume (ITV), covering the trajectory of tumor motion, as a treatment target.
Purpose: To develop a novel multi-breath time-resolved (TR) 4DCT using the super-resolution reconstruction framework with TR 4D magnetic resonance imaging (TR-4DMRI) as guidance for patient-specific breathing irregularity assessment, overcoming the shortcomings of RC-4DCT, including binning artifacts and single-breath limitations.
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!