9 research outputs found
Quality Assurance of TPS: comparison of dose calculation for stereotactic patients in Eclipse and iPlan RT Dose
BackgroundQuality assurance (QA) in the radiation therapy planning process is essential to ensure accurate dose delivery to the patient and to minimize the possibility of accidental exposure. In recent years, several reports have been developed addressing issues related to the commissioning and quality assurance (QA) of RTPSs.AimTo evaluate the differences between dose distributions obtained with different dose calculation algorithms implemented in TPSs for stereotactic irradiation.Materials and MethodsBrainLab's iPlan v. 3.0.2 RT Dose calculates by pencil beam algorithm, while Eclipse v.7.5.18 (Varian Medical Systems) calculates by different types of pencil beam/AAA algorithms (selectable).ResultsThe largest difference was found in the lung patient, where a difference of 10.3% in the number of monitor units and 8.3% in dose to the isocentre occurred (with calculation by AAA algorithm of Eclipse in relation to iPlan PB algorithm). The average difference in all other cases (AAA compared to iPlan) was 2.2% for MUs and 1.5% for dose to the isocentre. The average difference in all other cases (PB compared to iPlan) was 1.9% for MUs and 3.2% for dose to the isocentre. When data were transferred from iPlan through DICOM RT to Eclipse, for all patients an isocentre shift was observed.ConclusionThe dose distribution calculated by three different photon calculation algorithms results in clinically significant dose differences in isodose distribution, especially in the area of high inhomogeneities
Dosimetric inter-institutional comparison in European radiotherapy centres: Results of IAEA supported treatment planning system audit.
BACKGROUND AND PURPOSE: One of the newer audit modalities operated by the International Atomic Energy Agency (IAEA) involves audits of treatment planning systems (TPS) in radiotherapy. The main focus of the audit is the dosimetry verification of the delivery of a radiation treatment plan for three-dimensional (3D) conformal radiotherapy using high energy photon beams. The audit has been carried out in eight European countries - Estonia, Hungary, Latvia, Lithuania, Serbia, Slovakia, Poland and Portugal. The corresponding results are presented.
MATERIAL AND METHODS: The TPS audit reviews the dosimetry, treatment planning and radiotherapy delivery processes using the \u27end-to-end\u27 approach, i.e. following the pathway similar to that of the patient, through imaging, treatment planning and dose delivery. The audit is implemented at the national level with IAEA assistance. The national counterparts conduct the TPS audit at local radiotherapy centres through on-site visits. TPS calculated doses are compared with ion chamber measurements performed in an anthropomorphic phantom for eight test cases per algorithm/beam. A set of pre-defined agreement criteria is used to analyse the performance of TPSs.
RESULTS: TPS audit was carried out in 60 radiotherapy centres. In total, 190 data sets (combination of algorithm and beam quality) have been collected and reviewed. Dosimetry problems requiring interventions were discovered in about 10% of datasets. In addition, suboptimal beam modelling in TPSs was discovered in a number of cases.
CONCLUSIONS: The TPS audit project using the IAEA methodology has verified the treatment planning system calculations for 3D conformal radiotherapy in a group of radiotherapy centres in Europe. It contributed to achieving better understanding of the performance of TPSs and helped to resolve issues related to imaging, dosimetry and treatment planning
EP-1403: Tolerance level assessment for different patient groups during clinical implementation of in vivo dosimetry
Occupational radiation dose of personnel involved in sentinel node biopsy procedure
Introduction
Sentinel node biopsy is a procedure used for axillary nodal staging in breast cancer surgery. The process uses radioactive 99mTc isotope for mapping the sentinel node(s) and all the staff involved in the procedure is potentially exposed to ionizing radiation. The colloid for radiolabelling (antimone-sulphide) with 99mTc isotope (half-life 6 h) is injected into the patient breast. The injection has activity of 18.5 MBq. The surgeon removes the primary tumor and detects active lymph nodes with gamma detection unit. The tumor as well as the active nodal tissue is transferred to pathologist for the definitive findings. The aim of the study was to measure dose equivalents to extremities and whole body for all staff and suggest practice improvement in order to minimize exposure risk.
Materials and methods
The measurements of the following operational quantities were performed: Hp(10) personal dose equivalent to whole body and Hp(0.07) to extremities for staff as well as ambiental dose for operating theatre and during injection.
Hp(0.07) were measured at surgeon’s finger by ring thermoluminescent dosimeter (TLD) type MTS-N, and reader RADOS RE2000. Surgeon and nurse were wearing TLD personal dosimeter at the chest level. Anesthesiologist and anesthetist were wearing electronic personal dosimeters, while pathologist was wearing ring TLD while manipulating tissue samples.
Electronic dosimeters used were manufactured by Polimaster, type PM1610.
All TLD and electronic dosimeters data were reported, including background radiation. Background radiation was also monitored separately. Personal TLDs are standard for this type of personal monitoring, provided by accredited laboratory.
Measurements of ambiental dose in workplaces of other staff involved around the patient was performed before the surgery took place, by calibrated survey meters manufactured by Atomtex, type 1667.
The study involved two surgeons and one pathologist, two anesthesiologists and three anesthetists during two months period.
Results and discussion
The doses received by all staff are evaluated using passive and active personal dosimeters and ambiental dose monitors and practice was improved based on results collected. Average annual whole body dose for all staff involved in the procedure was less than 0.8 mSv. Extremity dose equivalents to surgeon and pathologist were far below the limits set for professionally exposed (surgeon) and for public (pathologist).
Conclusions
Although has proven to be very safe for all staff, additional measures for radiation protection, in accordance to ALARA principle (As Low As Reasonably Achievable) should be conducted. The recommendations for practice improvement with respect to radiation protection were issued
Linear array measurements of enhanced dynamic wedge and treatment planning system (TPS) calculation for 15 MV photon beam and comparison with electronic portal imaging device (EPID) measurements
The 3rd ESTRO-EFOMP core curriculum for medical physics experts in radiotherapy
Purpose: To update the 2011 ESTRO-EFOMP core curriculum (CC) for education and training of medical physics experts (MPE)s working in radiotherapy (RT), in line with recent EU guidelines, and to provide a framework for European countries to develop their own curriculum. Material and methods: Since September 2019, 27 European MPEs representing ESTRO, EFOMP and National Societies, with expertise covering all subfields of RT physics, have revised the CC for recent advances in RT. The ESTRO and EFOMP Education Councils, all European National Societies and international stakeholders have been involved in the revision process. Results: A 4-year training period has been proposed, with a total of 240 ECTS (European Credit Transfer and Accumulation System). Training entrance levels have been defined ensuring the necessary physics and mathematics background. The concept of competency-based education has been reinforced by introducing the CanMEDS role framework. The updated CC includes (ablative) stereotactic-, MR-guided- and adaptive RT, particle therapy, advanced automation, complex quantitative data analysis (big data/artificial intelligence), use of biological images, and personalized treatments. Due to the continuously increasing RT complexity, more emphasis has been given to quality management. Clear requirements for a research project ensure a proper preparation of MPE residents for their central role in science and innovation in RT. Conclusion: This updated, 3rd edition of the CC provides an MPE training framework for safe and effective practice of modern RT, while acknowledging the significant efforts needed in some countries to reach this level. The CC can contribute to further harmonization of MPE training in Europe
The 3rd ESTRO-EFOMP core curriculum for medical physics experts in radiotherapy.
PURPOSE
To update the 2011 ESTRO-EFOMP core curriculum (CC) for education and training of medical physics experts (MPE)s working in radiotherapy (RT), in line with recent EU guidelines, and to provide a framework for European countries to develop their own curriculum.
MATERIAL AND METHODS
Since September 2019, 27 European MPEs representing ESTRO, EFOMP and National Societies, with expertise covering all subfields of RT physics, have revised the CC for recent advances in RT. The ESTRO and EFOMP Education Councils, all European National Societies and international stakeholders have been involved in the revision process.
RESULTS
A 4-year training period has been proposed, with a total of 240 ECTS (European Credit Transfer and Accumulation System). Training entrance levels have been defined ensuring the necessary physics and mathematics background. The concept of competency-based education has been reinforced by introducing the CanMEDS role framework. The updated CC includes (ablative) stereotactic-, MR-guided- and adaptive RT, particle therapy, advanced automation, complex quantitative data analysis (big data/artificial intelligence), use of biological images, and personalized treatments. Due to the continuously increasing RT complexity, more emphasis has been given to quality management. Clear requirements for a research project ensure a proper preparation of MPE residents for their central role in science and innovation in RT.
CONCLUSION
This updated, 3rd edition of the CC provides an MPE training framework for safe and effective practice of modern RT, while acknowledging the significant efforts needed in some countries to reach this level. The CC can contribute to further harmonization of MPE training in Europe