scholarly journals Analyses of integrated EPID images for on‐treatment quality assurance to account for interfractional variations in volumetric modulated arc therapy

2020 ◽  
Vol 21 (1) ◽  
pp. 110-116
Author(s):  
Norimasa Matsushita ◽  
Mitsuhiro Nakamura ◽  
Makoto Sasaki ◽  
Shinsuke Yano ◽  
Michio Yoshimura ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Volumetric Modulated Arc Therapy ◽  
Treatment Quality ◽  
Arc Therapy

Retrospective analysis of portal dosimetry pre-treatment quality assurance of prostate volumetric-modulated arc therapy (VMAT) plans

2017 ◽  
Vol 17 (1) ◽  
pp. 44-52 ◽  
Author(s):  
Borna Maraghechi ◽  
Jack Davis ◽  
Shyam Badu ◽  
Andre Fleck ◽  
Johnson Darko ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiation Therapy ◽  
Treatment Quality ◽  
Average Dose ◽  
Imaging Device ◽  
Passing Rate ◽  
Arc Therapy ◽  
Pre Treatment ◽  
Dose Difference

AbstractBackgroundElectronic portal imaging device (EPID) offers high-resolution digital image that can be compared with a predicted portal dose image. A very common method to quantitatively compare a measured and calculated dose distribution that is routinely used for quality assurance (QA) of volumetric-modulated arc therapy (VMAT) and intensity-modulated radiation therapy treatment plans is the evaluation of the gamma index. The purpose of this work was to evaluate the gamma passing rate (%GP), maximum gamma (γmax), average gamma (γave), maximum dose difference (DDmax) and the average dose difference (DDave) for various regions of interest using Varian’s implementation of three absolute dose gamma calculation techniques of improved, local, and combined improved and local.Methods and materialsWe analyzed 232 portal dose images from 100 prostate cancer patients’ VMAT plans obtained using the Varian EPID on TrueBeam Linacs.ResultsOur data show that the %GP, γmax and γave depend on the gamma calculation method and the acceptance criteria. Higher %GP values were obtained compared with both our current institutional action level and the American Association of Physicists in Medicine Task Group 119 recommendations.ConclusionsThe results of this study can be used to establish stricter action levels for pre-treatment QA of prostate VMAT plans. A stricter 3%/3 mm improved gamma criterion with a passing rate of 97% or the 2%/2 mm improved gamma criterion with a passing rate of 95% can be achieved without additional measurements or configurations.

Quality assurance of volumetric modulated arc therapy using Elekta Synergy

2009 ◽  
pp. 1-5 ◽  
Author(s):  
Akihiro Haga ◽  
Keiichi Nakagawa ◽  
Kenshiro Shiraishi ◽  
Saori Itoh ◽  
Atsuro Terahara ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Volumetric Modulated Arc Therapy ◽  
Arc Therapy

scholarly journals Physical dosimetry of volumetric modulated arc therapy (VMAT) using EPID and 2D array for quality assurance

2018 ◽  
Vol 49 (2) ◽  
pp. 477-484
Author(s):  
Ismail E. Mohamed ◽  
Ayman G. Ibrahim ◽  
Hamdy M. Zidan ◽  
Hesham S. El-Bahkiry ◽  
Adel Y. El-sahragti
Keyword(s):  
Quality Assurance ◽  
Volumetric Modulated Arc Therapy ◽  
Arc Therapy ◽  
2D Array

scholarly journals Positional Accuracy and Quality Assurance of Backup JAWs Required for Volumetric Modulated Arc Therapy

2012 ◽  
Vol 68 (11) ◽  
pp. 1486-1491
Author(s):  
Daisaku Tatsumi ◽  
Ryosei Nakada ◽  
Akinori Ienaga ◽  
Akane Yomoda ◽  
Makoto Inoue ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Volumetric Modulated Arc Therapy ◽  
Positional Accuracy ◽  
Arc Therapy

Quality assurance of volumetric-modulated arc therapy head and neck cancer treatment using PRESAGE® dosimeter

2018 ◽  
Vol 17 (4) ◽  
pp. 441-446 ◽  
Author(s):  
Jalil ur Rehman ◽  
Muhammad Isa ◽  
Nisar Ahmad ◽  
H. M. Noor ul Huda Khan Asghar ◽  
Zaheer A. Gilani ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Cancer Treatment ◽  
Head And Neck ◽  
Treatment Planning ◽  
Volumetric Modulated Arc Therapy ◽  
Planning System ◽  
Treatment Planning System ◽  
Ct Scans ◽  
Arc Therapy ◽  
Calculated Dose

AbstractBackgroundAccurate three-dimensional dosimetry is essential in modern radiotherapy techniques such as volumetric-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). In this research work, the PRESAGE® dosimeter was used as quality assurance (QA) tool for VMAT planning for head and neck (H&N) cancer.Material and methodComputer tomography (CT) scans of an Image Radiation Oncology Core (IROC) H&N anthropomorphic phantom with both IROC standard insert and PRESAGE® insert were acquired separately. Both CT scans were imported into the Pinnacle (9.4 version) TPS for treatment planning, where the structures [planning target volume (PTV), organs at risk) and thermoluminescent detectors (TLDs) were manually contoured and used to optimise a VMAT plan. Treatment planning was done using VMAT (dual arc: 182°–178°, 178°–182°). Beam profile comparisons and gamma analysis were used to quantify agreement with film, PRESAGE® measurement and treatment planning system (TPS) calculated dose distribution.ResultsThe average ratio of TLD measured to calculated doses at the four PTV locations in the H&N phantom were between 0·95 to 0·99 for all three VMAT deliveries. Dose profiles were taken along the left–right, the anterior–posterior and superior–inferior axes, and good agreement was found between the PRESAGE® and Pinnacle profile. The mean value of gamma results for three VMAT deliveries in axial and sagittal planes were found to be 94·24 and 93·16% when compared with film and Pinnacle, respectively. The average values comparing the PRESAGE® results and dose values calculated on Pinnacle were observed to be 95·29 and 94·38% in the said planes, respectively, using a 5%/3 mm gamma criteria.ConclusionThe PRESAGE® dose measurements and calculated dose of pinnacle show reasonable agreement in both axial and sagittal planes for complex dual arc VMAT treatment plans. In general, the PRESAGE® dosimeter is found to be a feasible QA tool of VMAT plan for H&N cancer treatment.

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