Treatment planning systems dosimetry auditing project in Portugal.

Published on Feb 1, 2014in Physica Medica2.485
· DOI :10.1016/J.EJMP.2013.03.008
Maria do Carmo Lopes39
Estimated H-index: 39
,
A. Cavaco1
Estimated H-index: 1
+ 23 AuthorsJoanna Izewska18
Estimated H-index: 18
(IAEA: International Atomic Energy Agency)
Sources
Abstract
Abstract Background and purpose The Medical Physics Division of the Portuguese Physics Society (DFM_SPF) in collaboration with the IAEA, carried out a national auditing project in radiotherapy, between September 2011 and April 2012. The objective of this audit was to ensure the optimal usage of treatment planning systems. The national results are presented in this paper. Material and methods The audit methodology simulated all steps of external beam radiotherapy workflow, from image acquisition to treatment planning and dose delivery. A thorax CIRS phantom lend by IAEA was used in 8 planning test-cases for photon beams corresponding to 15 measuring points (33 point dose results, including individual fields in multi-field test cases and 5 sum results) in different phantom materials covering a set of typical clinical delivery techniques in 3D Conformal Radiotherapy. Results All 24 radiotherapy centers in Portugal have participated. 50 photon beams with energies 4–18 MV have been audited using 25 linear accelerators and 32 calculation algorithms. In general a very good consistency was observed for the same type of algorithm in all centres and for each beam quality. Conclusions The overall results confirmed that the national status of TPS calculations and dose delivery for 3D conformal radiotherapy is generally acceptable with no major causes for concern. This project contributed to the strengthening of the cooperation between the centres and professionals, paving the way to further national collaborations.
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References18
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#1L. RutonjskiH-Index: 2
#2B. PetrovicH-Index: 6
Last. Joanna Izewska (IAEA: International Atomic Energy Agency)H-Index: 18
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Background Independent external audits play an important role in quality assurance programme in radiation oncology. The audit supported by the IAEA in Serbia was designed to review the whole chain of activities in 3D conformal radiotherapy (3D-CRT) workflow, from patient data acquisition to treatment planning and dose delivery. The audit was based on the IAEA recommendations and focused on dosimetry part of the treatment planning and delivery processes.
Source
#1David S Followill (University of Texas MD Anderson Cancer Center)H-Index: 46
#2Stephen F Kry (University of Texas MD Anderson Cancer Center)H-Index: 41
Last. Geoffrey S. Ibbott (University of Texas MD Anderson Cancer Center)H-Index: 47
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Delivery of accurate intensity-modulated radiation therapy (IMRT) or stereotactic radiotherapy depends on a multitude of steps in the treatment delivery process. These steps range from imaging of the patient to dose calculation to machine delivery of the treatment plan. Within the treatment planning system’s (TPS) dose calculation algorithm, various unique small field dosimetry parameters are essential, such as multileaf collimator modeling and field size dependence of the output. One of the lar...
Source
#1Jessica Lowenstein (University of Texas MD Anderson Cancer Center)H-Index: 10
#2Stephen F KryH-Index: 41
Last. David S FollowillH-Index: 46
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Purpose: Describe the Radiological Physics Center's (RPC) extensive standard dosimetry data set determined from on‐site audits measurements.Method and Materials: Measurements were made during on‐site audits to institutions participating in NCI funded cooperative clinical trials for 44 years using a 0.6cc cylindrical ionization chamber placed within the RPC's water tank. Measurements were made on Varian, Siemens, and Elekta/Philips accelerators for 11 different energies from 68 models of accelera...
Source
#2C. PeshnyakH-Index: 1
Last. Joanna IzewskaH-Index: 18
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#2C. H. ClementH-Index: 10
#3P. Ortiz. LópezH-Index: 1
Lessons from accidental exposures are, therefore, an invaluable resource for revealing vulnerable aspects of the practice of radiotherapy, and for providing guidance for the prevention of future occurrences. These lessons have successfully been applied to avoid catastrophic events with conventional technologies and techniques. Recommendations, for example, include the independent verification of beam calibration and independent calculation of the treatment times and monitor units for external be...
#1P. Ortiz LópezH-Index: 6
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Last. S. VatnitskyH-Index: 10
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: Disseminating the knowledge and lessons learned from accidental exposures is crucial in preventing re-occurrence. This is particularly important in radiation therapy; the only application of radiation in which very high radiation doses are deliberately given to patients to achieve cure or palliation of disease. Lessons from accidental exposures are, therefore, an invaluable resource for revealing vulnerable aspects of the practice of radiotherapy, and for providing guidance for the prevention ...
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#2Rainer SchmidtH-Index: 12
Last. S. Vatnitsky (IAEA: International Atomic Energy Agency)H-Index: 10
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Abstract Background and purpose The methodology developed by IAEA for dosimetric quality control of treatment planning systems has been tested in different hospitals through a pilot study. The aim was to verify the methodology and observe the range of deviations between planned and delivered doses in 3D conformal radiotherapy in situations close to a clinical setting. Material and methods The methodology was based on an anthropomorphic phantom representing the human thorax, and simulates the who...
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#1P. CarrascoH-Index: 13
#2Nuria JornetH-Index: 16
Last. Maria RibasH-Index: 24
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To evaluate the dose values predicted by several calculation algorithms in two treatment planning systems, Monte Carlo (MC) simulations and measurements by means of various detectors were performed in heterogeneous layer phantoms with water- and bone-equivalent materials. Percentage depth doses (PDDs) were measured with thermoluminescent dosimeters (TLDs), metal-oxide semiconductor field-effect transistors (MOSFETs), plane parallel and cylindrical ionization chambers, and beam profiles with film...
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Last. Seyyed Rabie Mahdi Mahdavi (IUMS: Iran University of Medical Sciences)H-Index: 1
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Background: It is recommended for each set of radiation data and algorithm that subtle deliberation is done regarding dose calculation accuracy. Knowing the errors in dose calculation for each treatment plan will result in an accurate estimate of the actual dose achieved by the tumor. Objective: This study aims to evaluate the equivalent path length (EPL) and equivalent tissue air ratio (ETAR) algorithms in radiation dose calculation.Material and Methods: In this experimental study, the TEC-DOC ...
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#1Maria Daniela Falco (University of Chieti-Pescara)H-Index: 11
#2M. FusellaH-Index: 8
Last. Marta CasatiH-Index: 14
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PURPOSE The influence of basic plan parameters such as slice thickness, grid resolution, algorithm type and field size on calculated small field output factors (OFs) was evaluated in a multicentric study. METHODS AND MATERIALS Three computational homogeneous water phantoms with slice thicknesses (ST) 1, 2 and 3 mm were shared among twenty-one centers to calculate OFs for 1x1, 2x2 and 3x3 cm2 field sizes (FSs) (normalized to 10x10 cm2 FS), with their own treatment planning system (TPS) and the en...
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Abstract Purpose The IAEA newly developed “end-to-end” audit methodology for on-site verification of IMRT dose delivery has been carried out in Portugal in 2018. The main goal was to evaluate the physical aspects of the head and neck (H&N) cancer IMRT treatments. This paper presents the national results. Methods All institutions performing IMRT treatments in Portugal, 20 out of 24, have voluntarily participated in this audit. Following the adopted methodology, a Shoulder, Head and Neck End-to-En...
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Abstract An audit methodology was developed and applied for output factor (OF) calculations in radiotherapy. The auditees were asked to calculate OFs for field sizes from 10 × 10 cm 2 to 2 × 2 cm 2 . Sixty five beams were audited; missing reference OFs were interpolated. The calculated OFs were in 73% of cases higher than the reference data. The smaller the field size, the higher the overestimations which were observed in the higher fraction of cases. Treatment planning systems generally overest...
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#1S. Kasmuri (UI: University of Indonesia)
Treatment Planning System (TPS) is an important modality that determines radiotherapy outcome. TPS requires input data obtained through commissioning and the potentially error occurred. Error in this stage may result in the systematic error. The aim of this study to verify the TPS dosimetry to know deviation range between calculated and measurement dose. This study used CIRS phantom 002LFC representing the human thorax and simulated all external beam radiotherapy stages. The phantom was scanned ...
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#1Daryoush Shahbazi-Gahrouei (IUMS: Isfahan University of Medical Sciences)H-Index: 17
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Background: Performing audits play an important role in quality assurance program in radiation oncology. Among different algorithms, TiGRT is one of the common application software for dose calculation. This study aimed to clinical implications of TiGRT algorithm to measure dose and compared to calculated dose delivered to the patients for a variety of cases, with and without the presence of inhomogeneities and beam modifiers. Materials and Methods: Nonhomogeneous phantom as quality dose verific...
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#2Sophie ChiavassaH-Index: 13
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Abstract Purpose Static beam intensity-modulated-radiation-therapy (IMRT) and/or Volumetric-Modulated-Arc-Therapy (VMAT) are now available in many regional radiotherapy departments. The aim of this multi-institutional audit was to design a new methodology based on radiochromic films to perform an independent quality control. Methods A set of data were sent to all participating centres for two clinical localizations: prostate and Head and Neck (H&N) cancers. The agreement between calculations and...
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#1Jacek WendykierH-Index: 2
Last. Piotr Wendykier (University of Warsaw)H-Index: 2
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Abstract Aim This work addresses the problem of treatment planning system commissioning by introducing a new method of determination of boundaries between high and low gradient in beam profile. Background The commissioning of a treatment planning system is a very important task in the radiation therapy. One of the main goals of this task is to compare two field profiles: measured and calculated. Applying points of 80% and 120% of nominal field size can lead to the incorrect determination of boun...
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#1Leon DunnH-Index: 14
#2Joerg Lehmann (RMIT: RMIT University)H-Index: 19
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This work presents the Australian Clinical Dosimetry Service's (ACDS) findings of an investigation of systematic discrepancies between treatment planning system (TPS) calculated and measured audit doses. Specifically, a comparison between the Anisotropic Analytic Algorithm (AAA) and other common dose-calculation algorithms in regions downstream (� 2 cm) from low-density material in anthropomorphic and slab phantom geometries is presented. Two measurement setups involving rectilinear slabphantoms...
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