scholarly journals Applications and benefits of using gradient percentage depth dose instead of percentage depth dose for electron and photon beams in radiotherapy

2021 ◽  
Vol 27 (1) ◽  
pp. 25-29
Author(s):  
Labinot Kastrati ◽  
Gezim Hodolli ◽  
Sehad Kadiri ◽  
Elvin Demirel ◽  
Lutfi Istrefi ◽  
...  
Keyword(s):  
Electron Beams ◽  
Published Data ◽  
Photon Beams ◽  
Data Set ◽  
Percentage Depth Dose ◽  
Depth Dose ◽  
Electron And Photon

Abstract Introduction: The aim of this study is to analyze the gradient of percentage depth dose for photon and electron beams of LINACs and to simplify the data set. Materials and Methods: Dosimetry measurements were performed in accordance with Technical Reports Series No. 398 IAEA. Results and discussion: The gradient of percentage depth dose was calculated and compared with the available published data. Conclusion: Instead of percentage depth dose for increasing and decreasing parts, the findings suggest using only two numbers for specific gradient of dose, separately. In this way, they can replace the whole set of the percentage depth dose (PDD).

scholarly journals Improving Clinical dosimetric Accuracy of cancer treatment using a special quality of Electron and Photon Beam

2021 ◽  
Vol 5 (3) ◽  
Author(s):  
Ayesha Ikhlaq ◽  
Saeed Ahmad Buzdar ◽  
Muhammad Usman Mustafa ◽  
Sana Salahuddin ◽  
Mehr-Un-Nisa ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Electron Beam ◽  
Electron Beams ◽  
Photon Beam ◽  
Field Size ◽  
External Beam Radiation ◽  
Photon Beams ◽  
Depth Dose ◽  
Electron And Photon

In external beam radiation therapy, electron and photon beams have extraordinary characteristics in the treatment of cancer. The electron and photon beam characteristic are essential to study before calibration of machine. This study focused on the dosimetric characteristics of different energies of electron beams for different field size. The basic objective of this work is, to calculate dosimetric parameters and characteristics of electron beam, specially depth dose characteristics along central axis. In this work, 6 MeV, 9 MeV, 12 MeV, 15 MeV and 18 MeV of electron beam and 6 MV and 15 MV of photon beam with different field size is used. Characteristics of depth dose of electron and photon beam in water have analyzed to provide better quality of radiation therapy treatment planning. The different beam characteristics are due to different interactions that occurs between electron beams giving them a definite range whereas photon beams are attenuated leading to dose deposition and much larger range with no definite end. Depth dose characteristics of electron and photon beams do not show same characteristics as interaction of beam with matter depends on the quality of beam. Attenuation and penetration factors change with changing dosimetric parameters. Complete analysis of dosimetric characteristics of electron and photon beam help to choose more accurate beam for the treatment of cancer. This work will help to increase accuracy in treatment of cancer with radiotherapy.

scholarly journals A modified formula for defining tissue phantom ratio of photon beams

2008 ◽  
Vol 33 (3) ◽  
pp. 92-97
Author(s):  
M Jahangir Alam ◽  
KS Rabbani ◽  
GA Zakaria ◽  
SM Akram Hussain ◽  
Adnan Kiber ◽  
...  
Keyword(s):  
Linear Accelerator ◽  
Measured Data ◽  
German Cancer Research ◽  
Photon Beams ◽  
Data Set ◽  
Surface Distance ◽  
Percentage Depth Dose ◽  
Depth Dose ◽  
Tissue Phantom ◽  
Modified Formula

Tissue phantom ratio (TPR), for square fields of various dimensions has been determined at varying depths in water. The dose in water has been measured at a fixed source-to-surface distance (SSD) of 100 cm and reference depth of 5 cm for 6 MV photon beam of Siemens Linear Accelerator Primus II in German Cancer Research Center (DKFZ), Heidelberg, Germany. A modified formula has been developed to calculate the TPR value for isocentric treatment. The present article describes the conversion of the measured data values into a comprehensive and consistent data set by the modified formula, that gives the TPR from Percentage Depth Dose (PDD) with depth as a function of field sizes from 10 mm x 10 mm up to 300 mm x 300 mm) and depth (from 0 mm to 300 mm).DOI = 10.3329/bmrcb.v33i3.1140Bangladesh Med Res Counc Bull 2007; 33: 92-97

scholarly journals Relevance of Combined Electron and Photon Beams in Radiotherapy of Head and Neck Cancers in the Era of Intensity-Modulated Radiotherapy

2020 ◽  
Author(s):  
Vinod Pandey ◽  
K. C. Pandey ◽  
N. K. Pant ◽  
L. P. Verma
Keyword(s):  
Head And Neck ◽  
Electron Beams ◽  
External Beam Radiotherapy ◽  
Intensity Modulated Radiotherapy ◽  
Modern Technology ◽  
Head And Neck Cancers ◽  
Photon Beams ◽  
Average Percentage ◽  
Intensity Modulated ◽  
Electron And Photon

Abstract Introduction External beam radiotherapy (EBRT) for head and neck (H&N) cancers continues to be delivered using varied technologies, ranging from the old two-dimensional conventional radiotherapy (2DRT) techniques to the modern three-dimensional conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), and volumetric modulated arc therapy (VMAT) in different centers in India. Due to limitations of spinal cord tolerance, electron and photon beams are combined in 2DRT and 3DCRT techniques for treating nodal volume of the H&N cases. However, many centers having modern technology practice IMRT/VMAT in place of electron beams. The purpose of this study is to analyze the role of combined electron and photon beams in radiotherapy of H&N cancers and its relevance in the modern era of IMRT/VMAT. Materials and Methods Data were collected through a survey conducted on cancer centers in India where radiotherapy is being given by 2DRT, 3DCRT, and IMR/VMAT for the treatment of head and neck cancers. Results The mean percentage of H&N (H&N) cases among all cases were 39.2% (standard deviation [SD]: 14.22), out of which 16.63% (SD: 20.83) were treated with a combination of photon and electron beams and 49.73% (SD: 37.41) were treated with IMRT/VMAT. The average percentage of H&N cases of government institutes was 38.39% (SD: 14.11) and that of private institutes was 40.14% (SD: 14.11). Patients treated with photon and electron combination and IMRT/VMAT were 22.19% (SD: 11.24) and 24.05% (SD: 23.99), respectively, in government institutes, and 10.29% (SD: 11.24) and 79.09% (SD: 26.75) in private institutes. Conclusion As per this study, we conclude that despite the availability of IMRT/VMAT, a combination of electron and photon beams is still relevant in India. Since a large proportion of the patients are still treated with the electron and photon combination, it is imperative that further studies on field–junction dosimetry should be conducted to ensure accurate dose delivery.

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.

PLASMA WAKES DRIVEN BY NEUTRINOS, PHOTONS AND ELECTRON BEAMS

2007 ◽  
Vol 21 (03n04) ◽  
pp. 343-350
Author(s):  
R. BINGHAM ◽  
L. O. SILVA ◽  
J. T. MENDONCA ◽  
P. K. SHUKLA ◽  
W. B. MORI ◽  
...  
Keyword(s):  
Single Particle ◽  
Electron Beams ◽  
Kinetic Equations ◽  
Particle Interactions ◽  
Photon Beams ◽  
Dense Plasmas ◽  
New Class ◽  
Collective Plasma ◽  
Collective Interactions ◽  
Electron And Photon

There is considerable interest in the propagation dynamics of intense electron and photon neutrino beams in a background dispersive medium such as dense plasmas, particularly in the search for a mechanism to explain the dynamics of type II supernovae. Neutrino interactions with matter are usually considered as single particle interactions. All the single particle mechanisms describing the dynamical properties of neutrino's in matter are analogous with the processes involving single electron interactions with a medium such as Compton scattering, and Cerenkov radiation etc. However, it is well known that beams of electrons moving through a plasma give rise to a new class of processes known as collective interactions such as two stream instabilities which result in either the absorption or generation of plasma waves. Intense photon beams also drive collective interactions such as modulational type instabilities. In both cases relativistic electron beams of electrons and photon beams can drive plasma wakefields in plasmas. Employing the relativistic kinetic equations for neutrinos interacting with dense plasmas via the weak force we explore collective plasma streaming instabilities driven by Neutrino electron and photon beams and demonstrate that all three types of particles can drive wakefields.

scholarly journals Studies of Dosimetry Protocols for Accelerated Photons and Electrons Delivered from Medical Linear Accelerator

2021 ◽  
Keyword(s):  
Comparative Study ◽  
Linear Accelerator ◽  
Electron Beams ◽  
Absorbed Dose ◽  
Photon Beam ◽  
Photon Beams ◽  
Medical Linear Accelerator ◽  
The Comparative Study ◽  
Electron And Photon ◽  
Medical Linac

We focus on the comparative study of dosimetry protocols in radiotherapy for accelerated photon and electron delivered from medical linear accelerator (LINAC). In this study, a comparison between the protocols (TRS 398, DIN 6800-2 and TG 51) for both the electron and photon delivered from Clinac 2300CD and Clinac DHX 3186 were performed. We used photon beams with energies of 6 and 15 MV and electron beams of 4, 6, 9, 12, 15 and 18 MeV for both Medical Linac. In case of Clinac the maximum deviations for the relative dose at Dmax for the photon beam (15 MV) among the protocols was observed to be 1.18% between TRS-398 and TG-51, 1.56% between TG-51 and DIN 6800-2; and 0.41% between TRS-398 and DIN 6800-2. Conversely, these deviations were 3.67% between TRS-398 and TG-51, 3.92% between TG-51 and DIN 6800-2 for 4 MeV and 0.95% between TRS-398 and DIN 6800-2 in the case of Clinac 2300 CD for the PTW Markus and Exradin A10. For the measurement of the maximum absorbed dose depth to water using three protocols, the maximum deviations were observed between TRS 398 and TG-51 as well as TG51 and DIN 6800-2.

Polimer Gafchromic EBT3 Films in Clinical Dosimetry

2015 ◽  
Vol 1084 ◽  
pp. 572-576 ◽  
Author(s):  
Evgeniia Sukhikh ◽  
Leonid Sukhikh ◽  
Evgeniy Malikov
Keyword(s):  
Polymer Film ◽  
Electron Beams ◽  
Dose Range ◽  
Film Dosimetry ◽  
Photon Beams ◽  
Calibration Curves ◽  
Electron And Photon

The results of the calibration of the Gafchromic EBT3 polymer film for photon and electron beams with different energies are presented. The results of these studies show that the use of film dosimetry for electron and photon beams in the dose range 0.2 - 40 Gy is possible. The resulting calibration curves are the same for electrons with different energies (2 MeV, 10 MeV), but there exists a difference for photons with the energy of 10 MV and 70 kV.

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