Determination of prospective displacement-based gate threshold for respiratory-gated radiation delivery from retrospective phase-based gate threshold selected at 4D CT simulation

2007 ◽  
Vol 34 (11) ◽  
pp. 4247-4255 ◽  
Author(s):  
S. Vedam ◽  
L. Archambault ◽  
G. Starkschall ◽  
R. Mohan ◽  
S. Beddar
Keyword(s):  
4D Ct ◽  
Radiation Delivery ◽  
Ct Simulation ◽  
Displacement Based

TU-C-213CD-05: 4D-CT Simulation Using Individually Optimized Contrast Enhancement (CE): A Phantom Study

2012 ◽  
Vol 39 (6Part23) ◽  
pp. 3903-3903
Author(s):  
M Xue ◽  
W D'Souza ◽  
G Lasio ◽  
P Klahr ◽  
W Lu
Keyword(s):  
Contrast Enhancement ◽  
Phantom Study ◽  
4D Ct ◽  
Ct Simulation

scholarly journals Feasibility of 4D CT simulation with synchronized intravenous contrast injection in hepatocellular carcinoma

2020 ◽  
Vol 25 (2) ◽  
pp. 293-298
Author(s):  
Anil Gupta ◽  
Rishabh Kumar ◽  
Hanuman Prasad Yadav ◽  
Manik Sharma ◽  
Rose Kamal ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Contrast Injection ◽  
Intravenous Contrast ◽  
4D Ct ◽  
Ct Simulation

Determination of plasma displacement based on eddy current diagnostics for the Keda Torus eXperiment

2017 ◽  
Vol 24 (10) ◽  
pp. 102518 ◽  
Author(s):  
Cui Tu ◽  
Hong Li ◽  
Adi Liu ◽  
Zichao Li ◽  
Yuan Zhang ◽  
...  
Keyword(s):  
Eddy Current ◽  
Plasma Displacement ◽  
Displacement Based

The impact of four dimensions CT simulation on planning target volume in radiotherapy for primary lung cancer.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e20091-e20091
Author(s):  
Fawzi Jamil Abuhijla ◽  
Lubna Abdelrahman Hammoudeh ◽  
Ramiz Ahmad Abu-Hijlih ◽  
Jamal Khader
Keyword(s):  
Lung Cancer ◽  
Planning Target Volume ◽  
Tumor Volume ◽  
Multivariable Analysis ◽  
Primary Lung Cancer ◽  
Free Breathing ◽  
Target Volume ◽  
4D Ct ◽  
Ct Simulation ◽  
The Impact

e20091 Background: 4D CT simulation has been evolved to estimate the internal body motion and considered as a useful tool for intra-thoracic tumor definition. This study aimed to evaluate the impact of using 4D simulation on the planning target volume (PTV) for primary lung tumor. Methods: Patients who underwent CT simulation for primary lung cancer radiotherapy between 2012-2016 using 3D- (free breathing) and 4D- (respiratory gated) institutional protocol were included in this retrospective review. For each patient, gross tumor volume (GTV) was contoured in free breathing scan (3D-GTV), exhale scan (e-GTV) and inhale scan (i-GTV). The corresponding CTVs (3D-CTV, e-CTV and i-CTV) were created by adding 1 cm in all directions. 3D-internal target volume (3D-ITV) was generated by 0.5 cm cranio-caudal expansion of 3D-CTV, while 4D-ITV was created by combination of e-CTV and i-CTV. Subsequently, a 0.5 cm margin was added to generate the 3D-PTV and 4D-PTV respectively. The volumes of 3D-PTV and 4D-PTV were compared to examine the impact of 4D CT simulation on changes in the volume of PTV. Univariable and multivariable analysis were performed to test the impact of volume and location of GTV on the changes of PTV volume by more than 10 % between free breathing and respiratory gated scans. Results: A total of 10 patients were identified. The median [range] GTV, i-GTV, e-GTV volumes were 13.55 [1.44-628.66], 13.17 [1.77-627.36], 12.85 [1.34-630.25] cc respectively. The 3D-CTV, i-CTV, e-CTV volumes were 86.37 [23.76-1209], 84.97 [25.5- 1220.4], 83.40 [23.36-1224.12] cc respectively. 3D-ITV and 4D-ITV median volume was 106.06 [3.99-1422.8], 88.02 [20.51-1338.18] cc respectively. 3D-PTV was significantly larger than the 4D-PTV; median [range] volumes were 182.79 [58.65- 1861.05] vs. 158.21 [52.76-1771.02] cc, p = 0.0068). On multivariable analysis, neither the volume of GTV (p = 0.4917), nor the location of the tumor (peripheral, p = 0.4914 or lower location, p = 0.9594) had an in impact on PTV differences between free breathing and respiratory gated scans. Conclusions: The use of 4D simulation reduces the PTV for primary lung cancer, and it should be routinely implemented in clinical practice regardless the tumor volume or location.

Boundary integral equation evaluation of compression moduli of bonded rubber blocks

1983 ◽  
Vol 18 (4) ◽  
pp. 217-223 ◽  
Author(s):  
R T Fenner ◽  
E M Remzi
Keyword(s):  
Integral Equation ◽  
Boundary Integral Equation ◽  
Test Problem ◽  
Elastic Stress ◽  
Boundary Integral ◽  
Material Behaviour ◽  
Linear Elastic ◽  
Incompressible Materials ◽  
Displacement Based

The boundary integral equation (BIE) method for two-dimensional, linear, elastic stress analysis is applied to two plane strain problems involving either incompressible or nearly incompressible materials. One of these is a test problem with a known analytical solution, which facilitates checking of the accuracy of the numerical results. The other is the determination of compression moduli of bonded rubber blocks, for which some finite element (FE) solutions have been published previously. Comparison of the BIE and FE results suggests that the latter are increasingly inaccurate as the material behaviour approaches incompressibility. Unlike displacement-based FE methods, the BIE method is not subject to singularity problems when applied to incompressible materials.

Sign in / Sign up

Export Citation Format

Share Document