SU-E-T-09: Evaluation of Depth Dose Distribution with Limit Scatter Condition and Comparing with Treatment Planning System

2013 ◽  
Vol 40 (6Part10) ◽  
pp. 204-205
Author(s):  
P Zhou ◽  
I Das
Keyword(s):  
Treatment Planning ◽  
Dose Distribution ◽  
Planning System ◽  
Treatment Planning System ◽  
Depth Dose ◽  
Depth Dose Distribution

scholarly journals Quality Assurance of Dose Distribution of Photon Beam Planning by Anisotropic Analytical Algorithm (AAA)

2013 ◽  
Vol 4 (1) ◽  
pp. 43-49
Author(s):  
M Jahangir Alam ◽  
Syed Md Akram Hussain ◽  
Kamila Afroj ◽  
Shyam Kishore Shrivastava
Keyword(s):  
Quality Assurance ◽  
Treatment Planning ◽  
Dose Distribution ◽  
Maximum Dose ◽  
Photon Beam ◽  
Field Size ◽  
Planning System ◽  
Treatment Planning System ◽  
Anisotropic Analytical Algorithm ◽  
Analytical Algorithm

A three dimensional treatment planning system has been installed in the Oncology Center, Bangladesh. This system is based on the Anisotropic Analytical Algorithm (AAA). The aim of this study is to verify the validity of photon dose distribution which is calculated by this treatment planning system by comparing it with measured photon beam data in real water phantom. To do this verification, a quality assurance program, consisting of six tests, was performed. In this program, both the calculated output factors and dose at different conditions were compared with the measurement. As a result of that comparison, we found that the calculated output factor was in excellent agreement with the measured factors. Doses at depths beyond the depth of maximum dose calculated on-axis or off-axis in both the fields or penumbra region were found in good agreement with the measured dose under all conditions of energy, SSD and field size, for open and wedged fields. In the build up region, calculated and measured doses only agree (with a difference 2.0%) for field sizes > 5 × 5 cm2 up to 25 × 25 cm2. For smaller fields, the difference was higher than 2.0% because of the difficulty in dosimetry in that region. Dose calculation using treatment planning system based on the Anisotropic Analytical Algorithm (AAA) is accurate enough for clinical use except when calculating dose at depths above maximum dose for small field size.DOI: http://dx.doi.org/10.3329/bjmp.v4i1.14686 Bangladesh Journal of Medical Physics Vol.4 No.1 2011 43-49

scholarly journals Comparison of 3DCRT Dose Distribution in Radiotherapy for Lung Cancer Patient by Using AAA and PBC Algorithms

2016 ◽  
Vol 68 ◽  
pp. 54-60
Author(s):  
Muhammad Masud Rana ◽  
S.M. Azharul Islam ◽  
M. Moinul Islam ◽  
Md. Shakilur Rahman ◽  
Sarwar Alam ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Treatment Planning ◽  
Dose Distribution ◽  
Radiation Treatment ◽  
Planning System ◽  
Radiotherapy Planning ◽  
Treatment Planning System ◽  
Medical Systems ◽  
Calculation Algorithm ◽  
Conformal Radiation Therapy

The Pencil Beam Convolution (PBC) algorithm in radiation treatment planning system is widely used to calculate the radiation dose distribution in radiotherapy planning. A new photon dose calculation algorithm known as Anisotropic Analytical Algorithm (AAA) by Varian Medical Systems is applied to investigate the difference of dose distribution by using AAA and PBC algorithms for the lung cancer with an inhomogeneity of its low density. In the present work, radiotherapy treatment planning of 10 lung cancer patients are designed with 6 MV photon beam using three-dimensional conformal radiation therapy (3DCRT) and dose distribution was calculated by the AAA and the PBC Algorithms. The dose distribution performance is evaluated by dose profile curve along transversal slice of PTV and Dose Volume Histogram (DVH) covered by the 95% isodose of PTV. The mean dose of organ at risks did not changed significantly but the volume of the PTV covered by the 95% isodose curve was decreased by 6% with inhomogeneity due to the algorithms. The dose distribution and the accuracy in calculating the absorbed dose of the AAA algorithm of the Varian Eclipse treatment planning system is analyzed and discussed.

scholarly journals The Commissioning and Validation of EclipseTM Treatment Planning System on a Varian VitalBeamTM Medical Linear Accelerator for Photon and Electron Beams

2021 ◽  
Author(s):  
Samira Yazdani ◽  
Fateme Shirani Takabi ◽  
Abolfazl Nickfarjam
Keyword(s):  
Treatment Planning ◽  
Linear Accelerator ◽  
Electron Beams ◽  
Planning System ◽  
Treatment Planning System ◽  
Patient Treatment ◽  
Depth Dose ◽  
Tps Commissioning ◽  
Calculated Dose ◽  
Output Factors

Purpose: Commissioning of a linear accelerator is a process of acquiring a set of data used for patient treatment. This article presents the beam data measurement results from the commissioning of a VitalBeamTM linac. Materials and Methods: Dosimetric properties for 6,10, and 15 MV photon beams and 6, 9, 12, and 16 MeV electron beams have been performed. Parameters, including Percentage Depth Dose (PDD), depth dose profile, symmetry, flatness, quality index, output factors, and the vital data for Treatment Planning System (TPS) commissioning were measured. The imported data were checked by CIRS phantom accordingly to IAEA TRS-430, TECDOC. Eight different positions of CIRS phantom CT were planned and treated. Finally, the calculated dose at a determined position was compared with measuring data to TPS validation. Results: After comparing 84 points in a different plan, the 83 points were in agreement with the criteria, and just for one point in 15 MV failed. Conclusion: Commissioning of dose and field flatness and symmetry are in tolerance intervals given by Varian. This proves that the studied lines meet the specification and can be used in clinical practice with all available electron and photon energies.

scholarly journals Feasibility of a Reusable Radiochromic Dosimeter

2021 ◽  
Vol 11 (21) ◽  
pp. 9906
Author(s):  
Joseph R. Newton ◽  
Maxwell Recht ◽  
Joseph A. Hauger ◽  
Gabriel Segarra ◽  
Chase Inglett ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Optical Density ◽  
Dose Distribution ◽  
Ease Of Use ◽  
Planning System ◽  
Treatment Planning System ◽  
Patient Specific ◽  
High Dose ◽  
Wide Range ◽  
Radiochromic Dosimeter

The current practice for patient-specific quality assurance (QA) uses ion chambers or diode arrays primarily because of their ease of use and reliability. A standard routine compares the dose distribution measured in a phantom with the dose distribution calculated by the treatment planning system for the same experimental conditions. For the particular problems encountered in the treatment planning of complex radiotherapy techniques, such as small fields/segments and dynamic delivery systems, additional tests are required to verify the accuracy of dose calculations. The dose distribution verification should be throughout the total 3D dose distribution for a high dose gradient in a small, irradiated volume, instead of the standard practice of one to several planes with 2D radiochromic (GAFChromic) film. To address this issue, we have developed a 3D radiochromic dosimeter that improves the rigor of current QA techniques by providing high-resolution, complete 3D verification for a wide range of clinical applications. The dosimeter is composed of polyurethane, a radical initiator, and a leuco dye, which is radiolytically oxidized to a dye absorbing at 633 nm. Since this chemical dosimeter is single-use, it represents a significant expense. The purpose of this research is to develop a cost-effective reusable dosimeter formulation. Based on prior reusability studies, three promising dosimeter formulations were studied using small volume optical cuvettes and irradiated to known clinically relevant doses of 0.5–10 Gy. After irradiation, the change in optical density was measured in a spectrophotometer. All three formulations retained linearity of optical density response to radiation upon re-irradiations. However, only one formulation retained dose sensitivity upon at least five re-irradiations, making it ideal for further evaluation as a 3D dosimeter.

scholarly journals Integration of functional neuroimaging in CyberKnife radiosurgery: feasibility and dosimetric results

2013 ◽  
Vol 34 (4) ◽  
pp. E5 ◽  
Author(s):  
Alfredo Conti ◽  
Antonio Pontoriero ◽  
Giuseppe K. Ricciardi ◽  
Francesca Granata ◽  
Sergio Vinci ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Treatment Planning ◽  
Dose Distribution ◽  
Functional Neuroimaging ◽  
Brain Lesions ◽  
Morphological Data ◽  
Planning System ◽  
Treatment Planning System ◽  
Data Sets ◽  
Cyberknife Radiosurgery

Object The integration of state-of-the-art neuroimaging into treatment planning may increase the therapeutic potential of stereotactic radiosurgery. Functional neuroimaging, including functional MRI, navigated brain stimulation, and diffusion tensor imaging–based tractography, may guide the orientation of radiation beams to decrease the dose to critical cortical and subcortical areas. The authors describe their method of integrating functional neuroimaging technology into radiosurgical treatment planning using the CyberKnife radiosurgery system. Methods The records of all patients who had undergone radiosurgery for brain lesions at the CyberKnife Center of the University of Messina, Italy, between July 2010 and July 2012 were analyzed. Among patients with brain lesions in critical areas, treatment planning with the integration of functional neuroimaging was performed in 25 patients. Morphological and functional imaging data sets were coregistered using the Multiplan dedicated treatment planning system. Treatment planning was initially based on morphological data; radiation dose distribution was then corrected in relation to the functionally relevant cortical and subcortical areas. The change in radiation dose distribution was then calculated. Results The data sets could be easily and reliably integrated into the Cyberknife treatment planning. Using an inverse planning algorithm, the authors achieved an average 17% reduction in the radiation dose to functional areas. Further gain in terms of dose sparing compromised other important treatment parameters, including target coverage, conformality index, and number of monitor units. No neurological deficit due to radiation was recorded at the short-term follow-up. Conclusions Radiosurgery treatments rely on the quality of neuroimaging. The integration of functional data allows a reduction in radiation doses to functional organs at risk, including critical cortical areas, subcortical tracts, and vascular structures. The relative simplicity of integrating functional neuroimaging into radiosurgery warrants further research to implement, standardize, and identify the limits of this procedure.

scholarly journals Energy spectra considerations for synchrotron radiotherapy trials on the ID17 bio-medical beamline at the European Synchrotron Radiation Facility

2015 ◽  
Vol 22 (4) ◽  
pp. 1035-1041 ◽  
Author(s):  
Jeffrey C. Crosbie ◽  
Pauline Fournier ◽  
Stefan Bartzsch ◽  
Mattia Donzelli ◽  
Iwan Cornelius ◽  
...  
Keyword(s):  
Energy Spectrum ◽  
Synchrotron Radiation ◽  
Treatment Planning ◽  
European Synchrotron Radiation Facility ◽  
Planning System ◽  
Energy Spectra ◽  
Treatment Planning System ◽  
X Ray ◽  
Depth Dose ◽  
Cylindrical Ionization Chamber

The aim of this study was to validate the kilovoltage X-ray energy spectrum on the ID17 beamline at the European Synchrotron Radiation Facility (ESRF). The purpose of such validation was to provide an accurate energy spectrum as the input to a computerized treatment planning system, which will be used in synchrotron microbeam radiotherapy trials at the ESRF. Calculated and measured energy spectra on ID17 have been reported previously but recent additions and safety modifications to the beamline for veterinary trials warranted a fresh investigation. The authors used an established methodology to compare X-ray attenuation measurements in copper sheets (referred to as half value layer measurements in the radiotherapy field) with the predictions of a theoretical model. A cylindrical ionization chamber in air was used to record the relative attenuation of the X-ray beam intensity by increasing thicknesses of high-purity copper sheets. The authors measured the half value layers in copper for two beamline configurations, which corresponded to differing spectral conditions. The authors obtained good agreement between the measured and predicted half value layers for the two beamline configurations. The measured first half value layer was 1.754 ± 0.035 mm Cu and 1.962 ± 0.039 mm Cu for the two spectral conditions, compared with theoretical predictions of 1.763 ± 0.039 mm Cu and 1.984 ± 0.044 mm Cu, respectively. The calculated mean energies for the two conditions were 105 keV and 110 keV and there was not a substantial difference in the calculated percentage depth dose curves in water between the different spectral conditions. The authors observed a difference between their calculated energy spectra and the spectra previously reported by other authors, particularly at energies greater than 100 keV. The validation of the beam spectrum by the copper half value layer measurements means the authors can provide an accurate spectrum as an input to a treatment planning system for the forthcoming veterinary trials of microbeam radiotherapy to spontaneous tumours in cats and dogs.

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