Physical approach to depth dose distributions in a water phantom irradiated by a teleisotope photon beam

1980 ◽  
Vol 7 (2) ◽  
pp. 120-126 ◽  
Author(s):  
Sain D. Ahuja ◽  
Steven L. Stroup ◽  
Marion G. Bolin ◽  
S. Julian Gibbs
Keyword(s):  
Photon Beam ◽  
Dose Distributions ◽  
Water Phantom ◽  
Depth Dose ◽  
Physical Approach

Erratum: Physical approach to depth dose distributions in a water phantom irradiated by a teleisotope photon beam [Med. Phys. 7 , 120 (1980)]

1980 ◽  
Vol 7 (5) ◽  
pp. 550-550
Author(s):  
Sain D. Ahuja ◽  
Steven L. Stroup ◽  
Marion G. Bolin ◽  
S. Julian Gibbs
Keyword(s):  
Photon Beam ◽  
Dose Distributions ◽  
Water Phantom ◽  
Depth Dose ◽  
Physical Approach

scholarly journals Design and Analysis Effect of Gantry Angle Photon Beam 4 MV on Dose Distributions using Monte Carlo Method EGSnrc Code System

2016 ◽  
Vol 27 (1) ◽  
pp. 18-20
Author(s):  
Uum Yuliani ◽  
Ridwan Ramdani ◽  
Freddy Haryanto ◽  
Yudha Satya Perkasa ◽  
Mada Sanjaya
Keyword(s):  
Monte Carlo ◽  
Vertical Axis ◽  
Photon Beam ◽  
Field Size ◽  
Dose Calculations ◽  
Dose Distributions ◽  
Percentage Depth Dose ◽  
Depth Dose ◽  
Surface Field ◽  
Gantry Angle

Varian linac modeling has been carried out to obtain Percentage Depth Dose (PDD) and profiles using variations gantry angle 0o, 15o, 30o , 45o in the vertical axis of the surface, field size 10x10 cm2, photon beam 4 MV and Monte Carlo simulations. Percentage Depth Dose and profile illustrates dose distributions in a phantom water measuring 40x40x40 cm3, changes gantry is one of the factors that determine the distribution of the dose to the patient research shows changes in Dmax in the Percentage Depth Dose is affected by changes in the angle gantry resulted in the addition of the area build up so it can be used for therapy in the region and produce skin sparing effects that can be used to protect the skin from exposure to radiation. The graph result is profiles obtained show lack simetrisan in areas positive quadrant has a distribution of fewer doses than the quadrant of negative as well as the slope of the surface so that it can be used for some cases treatments that require a depth and a certain slope, dose calculations are more accurate and can minimize side effects.

scholarly journals Dosimetric Characterizations of Megavoltage Therapeutic Photon Beam

2020 ◽  
pp. 83-88
Author(s):  
Md. Abdullah Al Mashud ◽  
M. Jahangir Alam
Keyword(s):  
Photon Beam ◽  
Treatment System ◽  
Water Phantom ◽  
Percentage Depth Dose ◽  
Depth Dose ◽  
Dose Variation

This paper presents the dosimetric parameters characterizations of a megavoltage therapeutic photon beam. The main focus of this study is to investigate and analyze the parameters of percentage depth dose (PDD) and tissue maximum ratio (TMR) due to the importance of treatment system. The depth dose characteristics of 6MV photon beam for different field sizes in water phantom has been measured, analyzed and found a robustness results. The results revealed that the depth dose variation from 0.067% to 1.812% and the TMR values varies from 0.501% to 2.111%. It seems the measured dosimetric quantities are clinically relevant for different field sizes and depths.

scholarly journals Improving Animal-Specific Radiotherapy Quality Assurance For Kilovoltage X-Ray Radiotherapy Using A 3D Printed Dog Skull Water Phantom

2021 ◽  
Author(s):  
Yoshinori Tanabe ◽  
Toshie Iseri ◽  
Ryouta Onizuka ◽  
Takayuki Ishida ◽  
Hidetoshi Eto ◽  
...  
Keyword(s):  
Medical Education ◽  
Monte Carlo ◽  
Quality Assurance ◽  
Dose Assessment ◽  
Axis Ratio ◽  
Dose Distributions ◽  
X Ray ◽  
Water Phantom ◽  
Depth Dose ◽  
Orthovoltage Radiotherapy

Abstract Accurate dose assessment during animal radiotherapy is beneficial for veterinary medicine and medical education. We evaluated the dose distributions of kilovoltage X-ray orthovoltage radiotherapy and created a dog skull water phantom for animal-specific radiotherapy. EGSnrc-based BEAMnrc and DOSXYZnrc codes were used to simulate orthovoltage dose distributions. At 10, 20, 30, 40, 50 and 80 mm in a water phantom, depth dose was measured with waterproof Farmer dosimetry chambers and the diagonal off-axis ratio was measured with Gafchromic EBT3 film to simulate orthovoltage dose distributions. Energy differences between orthovoltage and linear accelerated radiotherapy were assessed with a heterogeneous bone and tissue virtual phantom. The animal-specific phantom for radiotherapy quality assurance was created from CT scans of a dog and printed with a three-dimensional printer using polyamide 12 nylon, with insertion points for dosimetry chambers and Gafchromic EBT3 film. Monte Carlo simulated and measured dose distributions differed by no more than 2.0% along the central axis up to a depth of 80 mm. The anode heel effect occurred in shallow areas. The orthovoltage radiotherapy percentage depth dose in bone was >40%. Build-up was >40%, with build-down after bone exit, whereas linear accelerator radiotherapy absorption changed little in the bone. A highly water-impermeable, animal-specific dog skull water phantom could be created to evaluate dose distribution.Animal-specific water phantoms and Monte Carlo simulated pre-treatment radiotherapy is useful quality assurance for orthovoltage radiotherapy and yields a visually familiar phantom that will be useful for veterinary medical education.

scholarly journals Erratum: Semi-empirical model for depth dose distributions of megavoltage x-ray beams [Med. Phys. 7 , 537 (1980)]

1981 ◽  
Vol 8 (2) ◽  
pp. 251-251
Author(s):  
Sain D. Ahuja ◽  
Steven L. Stroup ◽  
Marion G. Bolin
Keyword(s):  
Empirical Model ◽  
Dose Distributions ◽  
X Ray ◽  
Depth Dose ◽  
Semi Empirical

Percentage depth dose fragmentation for investigating and assessing the photon beam dosimetry quality

2018 ◽  
Vol 18 (03) ◽  
pp. 280-284 ◽  
Author(s):  
Mohamed Bencheikh ◽  
Abdelmajid Maghnouj ◽  
Jaouad Tajmouati
Keyword(s):  
Exponential Decay ◽  
Target Volume ◽  
Photon Beam ◽  
Field Size ◽  
Photon Beams ◽  
Energy Agency ◽  
Percentage Depth Dose ◽  
Depth Dose ◽  
Beam Dosimetry

AbstractAimThe purpose of this study is to introduce a new approach to assess the dosimetry quality of photon beam with energy and irradiation field size. This approach is based on percentage depth dose (PDD) fragmentation for investigating the dosimetry quality.Materials and methodsFor the investigation of the dosimetry quality of 6 and 18 MV photon beams, we have proceeded to fragment the PDD at different field sizes. This approach checks the overall PDD and is not restricted to the exponential decay regions, as per the International Atomic Energy Agency Technical Reports Series No 398 and the American Association of Physicist in Medicine Task Group 51 recommendations.Results and discussionThe 6 MV photon beam deposited more energy in the target volume than the 18 MV photon beam. The dose delivered by the 6 MV beam is greater by a factor of 1·5 than that delivered by the 18 MV beam in the build-up region and the dose delivered by the 6 MV beam is greater by a factor of 2·6 than that delivered by the 18 MV beam in the electronic equilibrium and the exponential decay regions.ConclusionThe dose measured at different points of the beam is higher for 6 MV than for 18 MV photon beam. Therefore, the 6 MV beam is more dosimetrically efficient than the 18 MV beam. Using the proposed approach, we can assess the dosimetry quality by taking into account overall PDD not only in the exponential decay region but also in the field.

scholarly journals Degradation of proton depth dose distributions attributable to microstructures in lung‐equivalent material

2015 ◽  
Vol 42 (11) ◽  
pp. 6425-6432 ◽  
Author(s):  
Uwe Titt ◽  
Martin Sell ◽  
Jan Unkelbach ◽  
Mark Bangert ◽  
Dragan Mirkovic ◽  
...  
Keyword(s):  
Equivalent Material ◽  
Dose Distributions ◽  
Depth Dose

scholarly journals Commissioning Measurements of Electron Beam Using Montecarlo Algorithm on Truebeam STx® and Compariaon with Clinac iX Linear Accelerator

2021 ◽  
Vol 229 ◽  
pp. 01041
Author(s):  
Kamal Saidi ◽  
Redouane El Baydaoui ◽  
Hanae El Gouach ◽  
Othmane Kaanouch ◽  
Mohamed Reda Mesradi
Keyword(s):  
Electron Beam ◽  
Electron Beams ◽  
Measured Data ◽  
University Hospital ◽  
Field Size ◽  
Large Field ◽  
Water Phantom ◽  
Depth Dose ◽  
International University ◽  
The Absolute

TrueBeam STx latest generation linear accelerators (linacs) installed at Sheikh Khalifa International University Hospital in Casablanca, Morocco. The aim of this is to present and compare the result of the Electron commissioning measurement on TrueBeam Stx and clinac iX installed at Sheikh Khalifa International University Hospital in Casablanca, Morocco. A compariaon of eMC calculations and measurements for TrueBeam Stx were evaluated. Dosimetric parameters are systematically measured using a large water phantom 3D scanning system MP3 Water Phantom (PTW, Freiburg, Germany). The data of the electron beams commissioning including depth dose curves for each applicator, depth dose curves without applicator and the profile in air for a large field size 40x 40cm2, and the Absolute Dose (cGy/MU) for each applicator. All the data were examined and compared for five electron beams (E6MeV, E9MeV, E12MeV, E16MeV and E20MeV) of Varian’s TrueBeam STx and Clinac iX machines. A comparison, between measurement PDDs and calculated by the Eclipse electron Monte Carlo (eMC) algorithm were performed to validate Truebeam Stx commissioning. All this measurements were performed with a Roos and Markus plane parallel chamber. Our measured data indicated that electron beam PDDs from the TrueBeam Stx machine are well matched to those from our Varian Clinac iX machine. Significant differences between TrueBeam and Clinac iX were found in in‐air profiles and open field output. Maximum depth dose for the TrueBeam Stx and Clinac iX for the following energies (6, 9, 12, 16, 20 MeV) are respectively (1.15; 1.89; 2.6; 3.1; and 2.35) and (1.24; 1.95; 2.70; 2.99 and 2.4cm). For the TrueBeam Stx and Clinac iX the quality index R50 for applicator 15x15 cm2 are in the tolerance intervals. Surface dose increases by increasing energy for both machines. The Absolute Dose (cGy/MU) calibrated for both machine in Dmax at 1cGy/MU for the reference field size cone 15x15 cm2. Bremsstrahlung tail Rp per energy levels as follows for the TrueBeam Stx : 6 MeV – 2.85 cm, 9 MeV – 4.28 cm, 12 MeV – 5.97 cm, 16 MeV – 7.88 cm and 20 MeV – 9.86 cm. and for the Clinac iX : 6 MeV – 2.86 cm, 9 MeV – 4.32 cm, 12 MeV – 5.96 cm, 16 MeV – 7.93 cm and 20 MeV – 10.08 cm. A good agreement between modeled and measured data is observed.

SU-E-T-723: Pencil Beam Depth-Dose Distributions in the Astroid TPS

2011 ◽  
Vol 38 (6Part22) ◽  
pp. 3657-3657
Author(s):  
B Clasie ◽  
H Kooy ◽  
N Depauw ◽  
C Goma ◽  
A Carabe-Fernandez ◽  
...  
Keyword(s):  
Pencil Beam ◽  
Dose Distributions ◽  
Depth Dose ◽  
Beam Depth
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