SUFT381: Fast Calculation of ThreeDimensional Dose Considering MLC Leaf Positional Errors for VMAT Plans
Abstract
Purpose: In this study, we developed a system to calculate three dimensional (3D) dose that reflects dosimetric error caused by leaf miscalibration for head and neck and prostate volumetric modulated arc therapy (VMAT) without additional treatment planning system calculation on real time. Methods: An original system called clarkson dose calculation based dosimetric error calculation to calculate dosimetric error caused by leaf miscalibration was developed by MATLAB (Math Works, Natick, MA). Our program, first, calculates point doses at isocenter for baseline and modified VMAT plan, which generated by inducing MLC errors that enlarged aperture size of 1.0 mm with clarkson dose calculation. Second, error incuced 3D dose was generated with transforming TPS baseline 3D dose using calculated point doses. Results: Mean computing time was less than 5 seconds. For seven head and neck and prostate plans, between our method and TPS calculated error incuced 3D dose, the 3D gamma passing rates (0.5%/2 mm, global) are 97.6±0.6% and 98.0±0.4%. The dose percentage change with dose volume histogram parameter of mean dose on target volume were 0.1±0.5% and 0.4±0.3%, and with generalized equivalent uniform dose on target volume were −0.2±0.5% and 0.2±0.3%. Conclusion: The erroneous 3D dose calculated by our method is usefulmore »
 Authors:
 Takeda General Hospital, Aizuwakamatsu City, Fukushima (Japan)
 (Japan)
 Tohoku University Graduate School of Medicine, Sendal, Miyagi (Japan)
 Publication Date:
 OSTI Identifier:
 22648979
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Medical Physics; Journal Volume: 43; Journal Issue: 6; Other Information: (c) 2016 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 60 APPLIED LIFE SCIENCES; 61 RADIATION PROTECTION AND DOSIMETRY; DOSIMETRY; ERRORS; PLANNING; RADIATION DOSES; RADIOTHERAPY; THREEDIMENSIONAL CALCULATIONS
Citation Formats
Katsuta, Y, Tohoku University Graduate School of Medicine, Sendal, Miyagi, Kadoya, N, Jingu, K, Shimizu, E, and Majima, K. SUFT381: Fast Calculation of ThreeDimensional Dose Considering MLC Leaf Positional Errors for VMAT Plans. United States: N. p., 2016.
Web. doi:10.1118/1.4956566.
Katsuta, Y, Tohoku University Graduate School of Medicine, Sendal, Miyagi, Kadoya, N, Jingu, K, Shimizu, E, & Majima, K. SUFT381: Fast Calculation of ThreeDimensional Dose Considering MLC Leaf Positional Errors for VMAT Plans. United States. doi:10.1118/1.4956566.
Katsuta, Y, Tohoku University Graduate School of Medicine, Sendal, Miyagi, Kadoya, N, Jingu, K, Shimizu, E, and Majima, K. 2016.
"SUFT381: Fast Calculation of ThreeDimensional Dose Considering MLC Leaf Positional Errors for VMAT Plans". United States.
doi:10.1118/1.4956566.
@article{osti_22648979,
title = {SUFT381: Fast Calculation of ThreeDimensional Dose Considering MLC Leaf Positional Errors for VMAT Plans},
author = {Katsuta, Y and Tohoku University Graduate School of Medicine, Sendal, Miyagi and Kadoya, N and Jingu, K and Shimizu, E and Majima, K},
abstractNote = {Purpose: In this study, we developed a system to calculate three dimensional (3D) dose that reflects dosimetric error caused by leaf miscalibration for head and neck and prostate volumetric modulated arc therapy (VMAT) without additional treatment planning system calculation on real time. Methods: An original system called clarkson dose calculation based dosimetric error calculation to calculate dosimetric error caused by leaf miscalibration was developed by MATLAB (Math Works, Natick, MA). Our program, first, calculates point doses at isocenter for baseline and modified VMAT plan, which generated by inducing MLC errors that enlarged aperture size of 1.0 mm with clarkson dose calculation. Second, error incuced 3D dose was generated with transforming TPS baseline 3D dose using calculated point doses. Results: Mean computing time was less than 5 seconds. For seven head and neck and prostate plans, between our method and TPS calculated error incuced 3D dose, the 3D gamma passing rates (0.5%/2 mm, global) are 97.6±0.6% and 98.0±0.4%. The dose percentage change with dose volume histogram parameter of mean dose on target volume were 0.1±0.5% and 0.4±0.3%, and with generalized equivalent uniform dose on target volume were −0.2±0.5% and 0.2±0.3%. Conclusion: The erroneous 3D dose calculated by our method is useful to check dosimetric error caused by leaf miscalibration before pre treatment patient QA dosimetry checks.},
doi = {10.1118/1.4956566},
journal = {Medical Physics},
number = 6,
volume = 43,
place = {United States},
year = 2016,
month = 6
}

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Practical aspects and uncertainty analysis of biological effective dose (BED) regarding its threedimensional calculation in multiphase radiotherapy treatment plans
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SUFT277: Using Dose Weighted Mean Effective Depth to Improve Accuracy of Secondary MU Calculation for VMAT Plans
Purpose: In commercial secondary dose calculation system, an average effective depth is used to calculate the Monitor Units for an arc beam from the volumetric modulated arc (VMAT) plans. Typically, an arithmetic mean of the effective depths (AMED) of a VMAT arc beam is used, which may result in large MU discrepancy from that of the primary treatment planning system. This study is to demonstrate the use of a dose weighted mean effective depth (DWED) can improve accuracy of MU calculation for the secondary MU verification. Methods: Inhouse scripts were written in the primary treatment planning system (TPS) to firstmore » 
SUFT386: Analysis of Three QA Methods for Predicting Dose Deviation Pass Percentage for Lung SBRT VMAT Plans
Purpose: To investigate the significance of using pinpoint ionization chambers (IC) and RadCalc (RC) in determining the quality of lung SBRT VMAT plans with low dose deviation pass percentage (DDPP) as reported by ScandiDos Delta4 (D4). To quantify the relationship between DDPP and point dose deviations determined by IC (ICDD), RadCalc (RCDD), and median dose deviation reported by D4 (D4DD). Methods: Point dose deviations and D4 DDPP were compiled for 45 SBRT VMAT plans. Eighteen patients were treated on Varian Truebeam linear accelerators (linacs); the remaining 27 were treated on Elekta Synergy linacs with Agility collimators. A oneway analysis ofmore »