Evaluation of depth-dose profiles in a water phantom at the BNCT facility at BINP

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.

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Bremsstrahlung Spectrum Reconstruction from Gradient Depth Dose Curves Obtained in a Water Phantom

Nuclear Technology ◽

10.13182/nt11-a12287 ◽

2011 ◽

Vol 175 (1) ◽

pp. 175-181 ◽

Cited By ~ 2

Author(s):

B. Juste ◽

R. Miró ◽

G. Verdú ◽

S. Díez ◽

J. M. Campayo

Keyword(s):

Bremsstrahlung Spectrum ◽

Spectrum Reconstruction ◽

Water Phantom ◽

Depth Dose

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Dosimetric Characterizations of Megavoltage Therapeutic Photon Beam

Annual Research & Review in Biology ◽

10.9734/arrb/2020/v35i930280 ◽

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.

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Neutron beam depth — dose dosimetry in a water phantom using an ionization chamber and SSNTDs

International Journal of Radiation Applications and Instrumentation Part D Nuclear Tracks and Radiation Measurements ◽

10.1016/1359-0189(90)90163-r ◽

1990 ◽

Vol 17 (1) ◽

pp. 72

Author(s):

L. Medveczky ◽

J. Hakl ◽

A. Fenyvesi

Keyword(s):

Neutron Beam ◽

Ionization Chamber ◽

Water Phantom ◽

Depth Dose ◽

Beam Depth

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Relative depth dose profile measurement in water phantom for Co-60 teletherapy machine using glycine (spectrophotometric read-out) system

Radiation Measurements ◽

10.1016/j.radmeas.2007.03.005 ◽

2007 ◽

Vol 42 (8) ◽

pp. 1419-1421

Author(s):

S.H. Shinde ◽

T. Mukherjee

Keyword(s):

Profile Measurement ◽

Relative Depth ◽

Water Phantom ◽

Dose Profile ◽

Depth Dose

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Depth dose measurement in water phantom for two X-ray energies (6MeV and 10MeV) in comparison with actual planning

Iraqi Journal of Science ◽

10.24996/ijs.2019.60.8.5 ◽

2019 ◽

pp. 1689-1693

Author(s):

Raghdah H. Hasan ◽

Samar I. Essa ◽

Manwar A. AL-Naqqash

Keyword(s):

Soft Tissue ◽

Field Size ◽

Vertical Position ◽

Dose Measurement ◽

High Similarity ◽

X Ray ◽

Water Phantom ◽

Percentage Depth Dose ◽

Depth Dose ◽

Different Depths

The purpose of this study is to measure doses delivered at different depths in water phantom at vertical position in comparison with the actual planning in order to verify the dose delivered to the tumor in addition to the measurement of the effect penumbra dose to assess the dose leaking to the healthy soft tissue. Percentage depth dose (PDD) values was measured at field sizes (5Ã—5,10Ã—10,15Ã—15, and 20Ã—20) cm2, and the depth dose was measured between (0-16) cm deep at 4cm intervals, for both energies 6 MeV and 10 MeV X-ray beam. Other readings were taken at different distances 1cm and 2cm outside of the actual beam in orthogonal directions at depth of 4 cm. These measurements were designed to measure the penumbra dose produced outside the central beam. Results show that the high similarity between water phantom and actual tissue for this reason water is taken as phantom for Quality Assurance (QA) and calculation the depth dose. The similar results may appear strange as the actual planning depth dose is taken in the chest wall where there is bone and soft tissue. The increase in the field size, increases the percentage of surface dose, this could be caused by an increase in the amount of scattering in the larger fields. There is almost no difference in depth dose between homogenous and non homogenous planning also similar to the water phantom. Because of higher photon energy 6MeV and 10MeV the bone has no influence in absorption from the soft tissue. A slight change in the depth dose with increase in the field size may be caused by the scattered radiation.

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Measurement of Percentage Depth Dose (PDD) for 6 MeV in water phantom and homogenous actual planning

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v16i37.70 ◽

2018 ◽

Vol 16 (37) ◽

pp. 1-6

Author(s):

Samar I. Essa

Keyword(s):

Ionizing Radiation ◽

Clinical Medicine ◽

Absorbed Dose ◽

Field Size ◽

X Ray ◽

Water Phantom ◽

Percentage Depth Dose ◽

Depth Dose ◽

Different Depths ◽

The Relationship

Radiotherapy is the branch of clinical medicine concerned with the application of ionizing radiation in the treatment of disease. And it is used to killing of cancer cells in a tissue using ionizing radiation while keeping the sparing of healthy cells at acceptable level. X-ray beams are used to deposit absorbed dose at depth within a patient at the site of the tumor. The aim of this work is studying the relationship between the depth dose and the field size in water phantom and homogenous actual planning. In our work, the dose distribution at different depths (zero-18 cm) deep at1cm interval treated with field size (10×10 and 20×20) cm2 were studied.Results show that high similarity between water phantom and actual planning for this reason water is taken as phantom for Quality Assurance (QA) and calculation the depth dose. When increasing the field size, the percentage of surface dose increases that this could be caused by an increase of the amount of scattering in the larger fields.Conclusion: There is almost no difference in depth dose between homogenous planning and water phantom.

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

10.21203/rs.3.rs-844438/v1 ◽

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.

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