BACKGROUND AND PURPOSE: Volumetric modulated arc therapy (VMAT) has the potential to deliver dose distributions comparable to the established intensity-modulated radiotherapy techniques for a multitude of target paradigms. Prior to implementing VMAT into their clinical routine in December 2008, the authors evaluated the dose calculation/delivery accuracy of 24 sample VMAT plans (prostate and anal cancer target paradigms) with film and ionization dosimetry. After the start of the clinical program, in vivo measurements with a rectal probe were performed. MATERIAL AND METHODS: The VMAT plans were generated by the treatment-planning system (TPS) ERGO++ (Elekta, Crawley, UK) and transferred to a phantom. Film dosimetry was performed with Kodak EDR2 films, and evaluated with dose profiles and gamma-index analysis. Appropriate ionization chambers were used for absolute dose measurements in the phantom and for in vivo measurements. The ionization chamber was used with localization of the measurement volume based on positioning cone-beam computed tomography. RESULTS: Plans were transferred from ERGO++ to the record and verify (R&V) system/linear accelerator (linac). The absolute dose deviations recorded with the ionization chamber were 1.74% +/- 1.62% across both indications. The gamma-index analysis of the film dosimetry showed no deviation > 3%/3 mm in the high-dose region. On in vivo measurements, a deviation between calculation and measurement of 2.09% +/- 2.4% was recorded, when the chamber was successfully positioned in the high-dose region. CONCLUSION: VMAT plans can be planned and treated reproducibly in high quality after the commissioning of the complete delivery chain consisting of TPS, R&V system and linac. The results of the individual plan verification meet the commonly accepted requirements. The first in vivo measurements confirm the reproducible precision of the delivered dose during clinical treatments.
BACKGROUND AND PURPOSE: Volumetric modulated arc therapy (VMAT) has the potential to deliver dose distributions comparable to the established intensity-modulated radiotherapy techniques for a multitude of target paradigms. Prior to implementing VMAT into their clinical routine in December 2008, the authors evaluated the dose calculation/delivery accuracy of 24 sample VMAT plans (prostate and anal cancer target paradigms) with film and ionization dosimetry. After the start of the clinical program, in vivo measurements with a rectal probe were performed. MATERIAL AND METHODS: The VMAT plans were generated by the treatment-planning system (TPS) ERGO++ (Elekta, Crawley, UK) and transferred to a phantom. Film dosimetry was performed with Kodak EDR2 films, and evaluated with dose profiles and gamma-index analysis. Appropriate ionization chambers were used for absolute dose measurements in the phantom and for in vivo measurements. The ionization chamber was used with localization of the measurement volume based on positioning cone-beam computed tomography. RESULTS: Plans were transferred from ERGO++ to the record and verify (R&V) system/linear accelerator (linac). The absolute dose deviations recorded with the ionization chamber were 1.74% +/- 1.62% across both indications. The gamma-index analysis of the film dosimetry showed no deviation > 3%/3 mm in the high-dose region. On in vivo measurements, a deviation between calculation and measurement of 2.09% +/- 2.4% was recorded, when the chamber was successfully positioned in the high-dose region. CONCLUSION: VMAT plans can be planned and treated reproducibly in high quality after the commissioning of the complete delivery chain consisting of TPS, R&V system and linac. The results of the individual plan verification meet the commonly accepted requirements. The first in vivo measurements confirm the reproducible precision of the delivered dose during clinical treatments.
Authors: G O De Meerleer; L A Vakaet; W R De Gersem; C De Wagter; B De Naeyer; W De Neve Journal: Int J Radiat Oncol Biol Phys Date: 2000-06-01 Impact factor: 7.038
Authors: Wim Duthoy; Werner De Gersem; Koen Vergote; Tom Boterberg; Cristina Derie; Peter Smeets; Carlos De Wagter; Wilfried De Neve Journal: Int J Radiat Oncol Biol Phys Date: 2004-11-01 Impact factor: 7.038
Authors: Frank Schneider; Martin Polednik; Dirk Wolff; Volker Steil; Anna Delana; Frederik Wenz; Loris Menegotti Journal: Z Med Phys Date: 2009 Impact factor: 4.820
Authors: M J Zelefsky; Z Fuks; L Happersett; H J Lee; C C Ling; C M Burman; M Hunt; T Wolfe; E S Venkatraman; A Jackson; M Skwarchuk; S A Leibel Journal: Radiother Oncol Date: 2000-06 Impact factor: 6.280
Authors: Wilko F A R Verbakel; Johan P Cuijpers; Daan Hoffmans; Michael Bieker; Ben J Slotman; Suresh Senan Journal: Int J Radiat Oncol Biol Phys Date: 2009-05-01 Impact factor: 7.038
Authors: James L Bedford; Vibeke Nordmark Hansen; Helen A McNair; Alexandra H Aitken; Juliet E C Brock; Alan P Warrington; Michael Brada Journal: Acta Oncol Date: 2008 Impact factor: 4.089
Authors: G Z Gong; Y Yin; L G Xing; Y J Guo; T Liu; J Chen; J Lu; C Ma; T Sun; T Bai; G Zhang; R Wang Journal: Strahlenther Onkol Date: 2012-02-08 Impact factor: 3.621
Authors: Dirk Van Gestel; Dirk Verellen; Lien Van De Voorde; Bie de Ost; Geert De Kerf; Olivier Vanderveken; Carl Van Laer; Danielle Van den Weyngaert; Jan B Vermorken; Vincent Gregoire Journal: Oncologist Date: 2013-05-30
Authors: F Röhner; M Schmucker; K Henne; F Momm; G Bruggmoser; A-L Grosu; H Frommhold; F E Heinemann Journal: Strahlenther Onkol Date: 2012-12-20 Impact factor: 3.621
Authors: P Hüttenrauch; M Witt; D Wolff; S Bosold; R Engenhart-Cabillic; J Sparenberg; H Vorwerk; K Zink Journal: Strahlenther Onkol Date: 2014-01-16 Impact factor: 3.621