J. Verstraete - Academia.edu (original) (raw)

Papers by J. Verstraete

Research paper thumbnail of The cost of radiotherapy in a decade of technology evolution

Radiotherapy and Oncology, 2012

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Research paper thumbnail of Implementation of volumetric modulated arc therapy for rectal cancer: Pitfalls and challenges

Acta Oncologica, 2015

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Research paper thumbnail of PD-0372: The cost of hadron therapy in Belgium: Comparison of a business model with activity-based costing

Radiotherapy and Oncology, 2013

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Research paper thumbnail of Salvage radiotherapy for biochemical failure after radical prostatectomy: long-term results from a single institution

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Research paper thumbnail of EP-1431: Implementing PRISMA-RT to analyze digitally reported (near) incidents and classify them for benchmarking

Radiotherapy and Oncology, 2014

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Research paper thumbnail of Time and motion study of radiotherapy delivery: Economic burden of increased quality assurance and IMRT

Radiotherapy and Oncology, 2009

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Research paper thumbnail of OC-0073: A comparitive study of four commercial thermoplastic masks used in head and neck radiotherapy

Radiotherapy and Oncology, 2013

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Research paper thumbnail of Hypofractionated intensity modulated irradiation for localized prostate cancer, results from a phase I/II feasibility study

Radiation Oncology, 2007

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Research paper thumbnail of 1253 poster LOCALIZATION AND REAL-TIME FIDUCIAL TRACKING OF THE PROSTATE WITH A RADIOACTIVE MARKER

Radiotherapy and Oncology, 2011

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Research paper thumbnail of Feasibility study of entrance in vivo dose measurements with mailed thermoluminescence detectors

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, 2004

The aim of this work is to set-up mailed entrance in vivo dosimetry by means of thermoluminescenc... more The aim of this work is to set-up mailed entrance in vivo dosimetry by means of thermoluminescence dosimeters (TLDs) in the form of LiF powder in order to assess the overall accuracy of patient treatment delivery by comparing the doses delivered to patients with the doses calculated by the treatment planning system (TPS) in different institutions. Two millimeter thick copper (for 6 MV photon beams) and 1.3 mm thick aluminium (for (60)Co gamma beams) build-up caps are developed. The characteristics of these build-up caps are tested by phantom measurements: the response of the TLD inside the build-up cap is compared to the ionisation chamber (IC) signal in the same irradiation conditions. A pilot study using the copper build-up cap is performed on 8 patients, treated with a 6 MV photon beam at the radiotherapy department of the University Hospital of Leuven. Additionally, a first run of mailed entrance in vivo dosimetry is performed by 18 radiotherapy centres in Europe. For 80 differe...

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Research paper thumbnail of Set-up verification on a belly-board device using electronic portal imaging

Journal of Radiotherapy …, 2007

Methods: First, we conducted a retrospective study in ten patients. Skin marks were used for set-... more Methods: First, we conducted a retrospective study in ten patients. Skin marks were used for set-up and the position was verified and corrected at the start of treatment by portal imaging. Second, we analysed the implementation of a more rigorous verification and correction ...

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Research paper thumbnail of SU‐FF‐T‐133: RapidArcTM: Commissioning and Dose Escalation Possibilities

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Research paper thumbnail of The use of a multipurpose phantom for mailed dosimetry checks of therapeutic photon beams: ‘OPERA’ (operational phantom for external radiotherapy audit)

Radiotherapy and Oncology, 2002

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Research paper thumbnail of Use of QA forms to register procedural errors in a radiotherapy department in an attempt to improve the overall process: a pilot study

Journal of Radiotherapy in Practice

Background and purpose: Due to the increased complexity of the radiotherapy process in recent yea... more Background and purpose: Due to the increased complexity of the radiotherapy process in recent years, many QA procedures have been introduced to improve the quality of the treatment preparation and the treatment delivery. Most of these procedures give no direct information on the efficiency of the overall process in the radiotherapy department. It is quite evident that the frequency of errors will affect the efficiency of the process (for instance manpower to solve the detected problems), but also affect more generally the patients' experience.Material and methods: To make some objective assessment of the erroneous entries in the process of radiotherapy, a pilot study was initiated to report all problems during a period of 2 months on a dedicated QA form. By registration of these errors, the QA group could trace the main sources of the decrease in efficiency and increased waiting time for patients.Results and conclusions: For 46% of the patients during the two months at least one...

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Research paper thumbnail of PD-0575: The dosimetrical advantage of prone position on a bellyboard for rectal cancer: does it still hold with VMAT?

Radiotherapy and Oncology

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Research paper thumbnail of In vivo dosimetry for tangential breast irradiation: role of the equipment in the accuracy of dose delivery

Radiotherapy and Oncology, 1991

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Research paper thumbnail of 14 EZ-port: precision radiation therapy skin marking system

Radiotherapy and Oncology, 1996

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Research paper thumbnail of Pre-treatment dosimetric verification by means of a liquid-filled electronic portal imaging device during dynamic delivery of intensity modulated treatment fields

Radiotherapy and Oncology, 2001

Although intensity modulated radiation therapy is characterized by three-dimensional dose distrib... more Although intensity modulated radiation therapy is characterized by three-dimensional dose distributions which are often superior to those obtained with conventional treatment plans, its routine clinical implementation is partially held back by the complexity of the beam verification. This is even more so when a dynamic multileaf collimator (dMLC) is used instead of a segmented beam delivery. We have therefore investigated the possibility of using a commercially available, liquid-filled electronic portal imaging device (EPID) for the pre-treatment quality assurance of dynamically delivered dose distributions. A special acquisition mode was developed to optimize the image acquisition speed for dosimetry with the liquid-filled EPID. We investigated the accuracy of this mode for 6 and 18 MV photon beams through comparison with film and ion chamber measurements. The impact of leaf speed and pulse rate fluctuations was quantified by means of dMLC plans especially designed for this purpose. Other factors influencing the accuracy of the dosimetry (e.g. the need for build-up, remanence of the ion concentration in the liquid and bulging of the liquid at non-zero gantry angles) were studied as well. We finally compared dosimetric EPID images with the corresponding image prediction delivered without a patient in the beam. The dosimetric accuracy of the measured dose distribution is approximately 2% with respect to film and ion chamber measurements. The accuracy declines when leaf speed is increased beyond 2 cm/s, but is fairly insensitive to accelerator pulse rate fluctuations. The memory effect is found to be of no clinical relevance. When comparing the acquired and expected distributions, an overall agreement of 3% can be obtained, except at areas of steep dose gradients where slight positional shifts are translated into large errors. Accurate dosimetric images of intensity modulated beam profiles delivered with a dMLC can be obtained with a commercially available, liquid-filled EPID. The developed acquisition mode is especially suited for fast and accurate pre-treatment verification of the intensity modulated fields.

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Research paper thumbnail of WE-D-224A-06: Comparison of Film Based IMRT Verification with EPID Based Fluence Verification

Medical Physics, 2006

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Research paper thumbnail of 173 oral PROCARE /RT PART/: IMPROVING CARE OF RECTAL CANCER IN BELGIUM BY STANDARDIZING CTV DELINEATION

Radiotherapy and Oncology, 2011

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Research paper thumbnail of The cost of radiotherapy in a decade of technology evolution

Radiotherapy and Oncology, 2012

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Implementation of volumetric modulated arc therapy for rectal cancer: Pitfalls and challenges

Acta Oncologica, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of PD-0372: The cost of hadron therapy in Belgium: Comparison of a business model with activity-based costing

Radiotherapy and Oncology, 2013

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Salvage radiotherapy for biochemical failure after radical prostatectomy: long-term results from a single institution

Bookmarks Related papers MentionsView impact

Research paper thumbnail of EP-1431: Implementing PRISMA-RT to analyze digitally reported (near) incidents and classify them for benchmarking

Radiotherapy and Oncology, 2014

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Time and motion study of radiotherapy delivery: Economic burden of increased quality assurance and IMRT

Radiotherapy and Oncology, 2009

Bookmarks Related papers MentionsView impact

Research paper thumbnail of OC-0073: A comparitive study of four commercial thermoplastic masks used in head and neck radiotherapy

Radiotherapy and Oncology, 2013

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Hypofractionated intensity modulated irradiation for localized prostate cancer, results from a phase I/II feasibility study

Radiation Oncology, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of 1253 poster LOCALIZATION AND REAL-TIME FIDUCIAL TRACKING OF THE PROSTATE WITH A RADIOACTIVE MARKER

Radiotherapy and Oncology, 2011

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Feasibility study of entrance in vivo dose measurements with mailed thermoluminescence detectors

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, 2004

The aim of this work is to set-up mailed entrance in vivo dosimetry by means of thermoluminescenc... more The aim of this work is to set-up mailed entrance in vivo dosimetry by means of thermoluminescence dosimeters (TLDs) in the form of LiF powder in order to assess the overall accuracy of patient treatment delivery by comparing the doses delivered to patients with the doses calculated by the treatment planning system (TPS) in different institutions. Two millimeter thick copper (for 6 MV photon beams) and 1.3 mm thick aluminium (for (60)Co gamma beams) build-up caps are developed. The characteristics of these build-up caps are tested by phantom measurements: the response of the TLD inside the build-up cap is compared to the ionisation chamber (IC) signal in the same irradiation conditions. A pilot study using the copper build-up cap is performed on 8 patients, treated with a 6 MV photon beam at the radiotherapy department of the University Hospital of Leuven. Additionally, a first run of mailed entrance in vivo dosimetry is performed by 18 radiotherapy centres in Europe. For 80 differe...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Set-up verification on a belly-board device using electronic portal imaging

Journal of Radiotherapy …, 2007

Methods: First, we conducted a retrospective study in ten patients. Skin marks were used for set-... more Methods: First, we conducted a retrospective study in ten patients. Skin marks were used for set-up and the position was verified and corrected at the start of treatment by portal imaging. Second, we analysed the implementation of a more rigorous verification and correction ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of SU‐FF‐T‐133: RapidArcTM: Commissioning and Dose Escalation Possibilities

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The use of a multipurpose phantom for mailed dosimetry checks of therapeutic photon beams: ‘OPERA’ (operational phantom for external radiotherapy audit)

Radiotherapy and Oncology, 2002

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Use of QA forms to register procedural errors in a radiotherapy department in an attempt to improve the overall process: a pilot study

Journal of Radiotherapy in Practice

Background and purpose: Due to the increased complexity of the radiotherapy process in recent yea... more Background and purpose: Due to the increased complexity of the radiotherapy process in recent years, many QA procedures have been introduced to improve the quality of the treatment preparation and the treatment delivery. Most of these procedures give no direct information on the efficiency of the overall process in the radiotherapy department. It is quite evident that the frequency of errors will affect the efficiency of the process (for instance manpower to solve the detected problems), but also affect more generally the patients' experience.Material and methods: To make some objective assessment of the erroneous entries in the process of radiotherapy, a pilot study was initiated to report all problems during a period of 2 months on a dedicated QA form. By registration of these errors, the QA group could trace the main sources of the decrease in efficiency and increased waiting time for patients.Results and conclusions: For 46% of the patients during the two months at least one...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of PD-0575: The dosimetrical advantage of prone position on a bellyboard for rectal cancer: does it still hold with VMAT?

Radiotherapy and Oncology

Bookmarks Related papers MentionsView impact

Research paper thumbnail of In vivo dosimetry for tangential breast irradiation: role of the equipment in the accuracy of dose delivery

Radiotherapy and Oncology, 1991

Bookmarks Related papers MentionsView impact

Research paper thumbnail of 14 EZ-port: precision radiation therapy skin marking system

Radiotherapy and Oncology, 1996

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Pre-treatment dosimetric verification by means of a liquid-filled electronic portal imaging device during dynamic delivery of intensity modulated treatment fields

Radiotherapy and Oncology, 2001

Although intensity modulated radiation therapy is characterized by three-dimensional dose distrib... more Although intensity modulated radiation therapy is characterized by three-dimensional dose distributions which are often superior to those obtained with conventional treatment plans, its routine clinical implementation is partially held back by the complexity of the beam verification. This is even more so when a dynamic multileaf collimator (dMLC) is used instead of a segmented beam delivery. We have therefore investigated the possibility of using a commercially available, liquid-filled electronic portal imaging device (EPID) for the pre-treatment quality assurance of dynamically delivered dose distributions. A special acquisition mode was developed to optimize the image acquisition speed for dosimetry with the liquid-filled EPID. We investigated the accuracy of this mode for 6 and 18 MV photon beams through comparison with film and ion chamber measurements. The impact of leaf speed and pulse rate fluctuations was quantified by means of dMLC plans especially designed for this purpose. Other factors influencing the accuracy of the dosimetry (e.g. the need for build-up, remanence of the ion concentration in the liquid and bulging of the liquid at non-zero gantry angles) were studied as well. We finally compared dosimetric EPID images with the corresponding image prediction delivered without a patient in the beam. The dosimetric accuracy of the measured dose distribution is approximately 2% with respect to film and ion chamber measurements. The accuracy declines when leaf speed is increased beyond 2 cm/s, but is fairly insensitive to accelerator pulse rate fluctuations. The memory effect is found to be of no clinical relevance. When comparing the acquired and expected distributions, an overall agreement of 3% can be obtained, except at areas of steep dose gradients where slight positional shifts are translated into large errors. Accurate dosimetric images of intensity modulated beam profiles delivered with a dMLC can be obtained with a commercially available, liquid-filled EPID. The developed acquisition mode is especially suited for fast and accurate pre-treatment verification of the intensity modulated fields.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of WE-D-224A-06: Comparison of Film Based IMRT Verification with EPID Based Fluence Verification

Medical Physics, 2006

Bookmarks Related papers MentionsView impact

Research paper thumbnail of 173 oral PROCARE /RT PART/: IMPROVING CARE OF RECTAL CANCER IN BELGIUM BY STANDARDIZING CTV DELINEATION

Radiotherapy and Oncology, 2011

Bookmarks Related papers MentionsView impact