AI Article Synopsis
- The study aimed to assess the effectiveness of four-dimensional cone beam CT (4DCBCT) imaging at various gantry rotation speeds using a dynamic thorax phantom that mimicked tumor motion.
- Different speeds (36° to 200° per minute) were tested, revealing that faster speeds resulted in greater underestimation of the internal target volume (ITV) and poorer image quality indicators like spatial resolution.
- The findings emphasized the importance of gantry rotation speed on ITV accuracy, indicating that slower speeds lead to better image quality and smaller deviations in ITV measurements.
Article Abstract
Objective: The purpose of this work was to evaluate the four-dimensional cone beam CT (4DCBCT) imaging with different gantry rotation speed.
Methods: All the 4DCBCT image acquisitions were carried out in Elekta XVI Symmetry™ system (Elekta AB, Stockholm, Sweden). A dynamic thorax phantom with tumour mimicking inserts of diameter 1, 2 and 3 cm was programmed to simulate the respiratory motion (4 s) of the target. 4DCBCT images were acquired with different gantry rotation speeds (36°, 50°, 75°, 100°, 150° and 200° min(-1)). Owing to the technical limitation of 4DCBCT system, average cone beam CT (CBCT) images derived from the 10 phases of 4DCBCT were used for the internal target volume (ITV) contouring. ITVs obtained from average CBCT were compared with the four-dimensional CT (4DCT). In addition, the image quality of 4DCBCT was also evaluated for various gantry rotation speeds using Catphan(®) 600 (The Phantom Laboratory Inc., Salem, NY).
Results: Compared to 4DCT, the average CBCT underestimated the ITV. The ITV deviation increased with increasing gantry speed (-10.8% vs -17.8% for 36° and 200° min(-1) in 3-cm target) and decreasing target size (-17.8% vs -26.8% for target diameter 3 and 1 cm in 200° min(-1)). Similarly, the image quality indicators such as spatial resolution, contrast-to-noise ratio and uniformity also degraded with increasing gantry rotation speed.
Conclusion: The impact of gantry rotation speed has to be considered when using 4DCBCT for ITV definition. The phantom study demonstrated that 4DCBCT with slow gantry rotation showed better image quality and less ITV deviation.
Advances In Knowledge: Usually, the gantry rotation period of Elekta 4DCBCT system is kept constant at 4 min (50° min(-1)) for acquisition, and any attempt of decreasing/increasing the acquisition duration requires careful investigation. In this study, the 4DCBCT images with different gantry rotation speed were evaluated.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4846214 | PMC |
| http://dx.doi.org/10.1259/bjr.20150870 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
An automated treatment planning portfolio for whole breast radiotherapy.
Med Phys
December 2024
The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, Houston, Texas, USA.
Background: Automation in radiotherapy presents a promising solution to the increasing cancer burden and workforce shortages. However, existing automated methods for breast radiotherapy lack a comprehensive, end-to-end solution that meets varying standards of care.
Purpose: This study aims to develop a complete portfolio of automated radiotherapy treatment planning for intact breasts, tailored to individual patient factors, clinical approaches, and available resources.
Development of a new VMAT QA framework for Mobius3D using control-point specific EPID images.
Front Oncol
December 2024
Medical Physics and Biomedical Engineering Lab (MPBEL), Yonsei University College of Medicine, Seoul, Republic of Korea.
Purpose: This study presents novel quality assurance (QA) approach for volumetric modulated arc therapy (VMAT) that leverages frame-by-frame electronic portal imaging device (EPID) images integrated into Mobius3D for accurate three-dimensional dose calculations.
Methods: Sequential EPID images for VMAT plans were acquired every 0.4-second by iView system and processed through iterative deconvolution to mitigate blurring from photon scattering.
Diagnostic Accuracy of Dynamic Stress Myocardial CT Perfusion Compared with Invasive Physiology in Patients with Stents: The Advantage 2 Study.
Radiology
December 2024
From the Centro Cardiologico Monzino, IRCCS, Via C. Belgioioso 173, Milan, Italy (D.A., S.M., D.T., E.C., G.L., S. Galli, G.M., L.G., G.T., S.T., S. Gili, P.M., P.O., V.M., D.M., M.S., C.G., E.M., A.B., M.E.M., A.A., A F., G.P., A.L.B.); Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy (D.A.); IRCCS Ospedale Galeazzi Sant'Ambrogio, Milan, Italy (E.C., G.M., L.G., V.M., D.M., M.S., E.G., P.P., E.M., A.L.B.); Cardiovascular Center Aalst, OLV Hospital, Aalst, Belgium (J.S., M.B., E.G., P.P., K.S., T.M., C.C.); Department of Medicine, Division of Cardiology, Showa University School of Medicine, Tokyo, Japan (K.S., T.M.); Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy (G.P.); and Department of Radiology, Azienda Ospedaliera di Padova, Padua, Italy (L.Z.).
Background The detection of in-stent restenosis (ISR) with coronary CT angiography (CCTA) is challenging, but CT perfusion (CTP) has demonstrated improved diagnostic accuracy over CCTA in patients with stents. However, there are limited data on the performance of dynamic CTP, which allows noninvasive adjudication of regional myocardial blood flow. Purpose To compare the diagnostic performance of regadenoson-stress dynamic CTP with that of CCTA, using fractional flow reserve (FFR) and the index of microvascular resistance (IMR) as reference standards for epicardial coronary circulation and coronary microcirculation, respectively.
View Article and Find Full Text PDFMulti-IMPT: a biologically equivalent approach to proton ARC therapy.
ArXiv
November 2024
Department of Radiation Oncology, University of Kansas Medical Center, USA.
Objective: Proton spot-scanning arc therapy (ARC) is an emerging modality that can improve the high-dose conformity to targets compared with standard intensity-modulated proton therapy (IMPT). However, the efficient treatment delivery of ARC is challenging due to the required frequent energy changes during the continuous gantry rotation. This work proposes a novel method that delivers a multiple IMPT (multi-IMPT) plan that is equivalent to ARC in terms of biologically effective dose (BED).
View Article and Find Full Text PDFFive-year evaluation of linear accelerator-based SRS platform isocentricity.
J Appl Clin Med Phys
December 2024
Department of Radiation Oncology, Willis Knighton Cancer Center, Shreveport, Louisiana, USA.
Linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) has become a mainstay in the management of intracranial tumors. However, the high fractional doses and sharp gradients used in SRS place heavy demands on geometric accuracy. Image guidance systems such as ExacTrac (ETX, Brainlab AG, Munich, Germany) have been developed to facilitate position verification at nonzero table angles.
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!