P B Greer

Summary

Affiliation: New South Wales
Country: Australia

Publications

  1. ncbi Comparison of prostate set-up accuracy and margins with off-line bony anatomy corrections and online implanted fiducial-based corrections
    P B Greer
    Department of Radiation Oncology, Calvary Mater Newcastle Hospital, 2University of Newcastle, Newcastle, Australia
    J Med Imaging Radiat Oncol 52:511-6. 2008
  2. ncbi Assessment of a daily online implanted fiducial marker-guided prostate radiotherapy process
    P B Greer
    Radiation Oncology Department, Calvary Mater Newcastle Hospital, University of Newcastle, Newcastle, New South Wales, Australia
    J Med Imaging Radiat Oncol 52:517-24. 2008
  3. ncbi Experimental investigation of the response of an amorphous silicon EPID to intensity modulated radiotherapy beams
    Peter B Greer
    Calvary Mater Newcastle Hospital, Newcastle, New South Wales, Australia
    Med Phys 34:4389-98. 2007
  4. ncbi Off-axis dose response characteristics of an amorphous silicon electronic portal imaging device
    Peter B Greer
    Calvary Mater Newcastle Hospital, Newcastle, New South Wales, Australia
    Med Phys 34:3815-24. 2007
  5. ncbi Investigation of an amorphous silicon EPID for measurement and quality assurance of enhanced dynamic wedge
    Peter B Greer
    Radiation Oncology Department, Newcastle Mater Hospital, and Physics and Mathematical Physics, University of Newcastle, Newcastle, New South Wales 2298, Australia
    Phys Med Biol 52:1075-87. 2007
  6. ncbi An energy fluence-convolution model for amorphous silicon EPID dose prediction
    Peter B Greer
    Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Locked Bag 7, Hunter Region Mail Centre, Newcastle, NSW 2310, Australia
    Med Phys 36:547-55. 2009
  7. ncbi Correction of pixel sensitivity variation and off-axis response for amorphous silicon EPID dosimetry
    Peter B Greer
    Newcastle Mater Hospital, and University of Newcastle, Newcastle, New South Wales, Australia
    Med Phys 32:3558-68. 2005
  8. ncbi Improving the resolution of dynamic intensity modulated radiation therapy delivery by reducing the multileaf collimator sampling distance
    Peter B Greer
    B C Cancer Agency, Vancouver Island Center, Victoria, B C, Canada
    Med Phys 30:2793-803. 2003
  9. ncbi The effect of leaf width and sampling distance on the "stair-stepping" of field borders defined by multileaf collimators
    P B Greer
    Department of Medical Physics, BC Cancer Agency, Vancouver Island Centre, Victoria, V8R 6V5, Canada
    Australas Phys Eng Sci Med 26:45-52. 2003
  10. ncbi Dosimetric properties of an amorphous silicon electronic portal imaging device for verification of dynamic intensity modulated radiation therapy
    Peter B Greer
    Department of Medical Physics, B C Cancer Agency, Vancouver Island Centre, 2410 Lee Avenue, Victoria V8R 6V5, Canada
    Med Phys 30:1618-27. 2003

Detail Information

Publications29

  1. ncbi Comparison of prostate set-up accuracy and margins with off-line bony anatomy corrections and online implanted fiducial-based corrections
    P B Greer
    Department of Radiation Oncology, Calvary Mater Newcastle Hospital, 2University of Newcastle, Newcastle, Australia
    J Med Imaging Radiat Oncol 52:511-6. 2008
    ..The margin required for set-up errors was found to be 10-15 mm unless implanted fiducial markers are available for treatment guidance...
  2. ncbi Assessment of a daily online implanted fiducial marker-guided prostate radiotherapy process
    P B Greer
    Radiation Oncology Department, Calvary Mater Newcastle Hospital, University of Newcastle, Newcastle, New South Wales, Australia
    J Med Imaging Radiat Oncol 52:517-24. 2008
    ..The inability in the current software to incorporate in-plane prostate rotations is a limitation that should not introduce large errors, provided that the treatment isocentre is positioned near the centre of the prostate...
  3. ncbi Experimental investigation of the response of an amorphous silicon EPID to intensity modulated radiotherapy beams
    Peter B Greer
    Calvary Mater Newcastle Hospital, Newcastle, New South Wales, Australia
    Med Phys 34:4389-98. 2007
    ..Accounting for the difference in EPID response to open and MLCtr radiation should improve IMRT dosimetry with a-Si EPIDs...
  4. ncbi Off-axis dose response characteristics of an amorphous silicon electronic portal imaging device
    Peter B Greer
    Calvary Mater Newcastle Hospital, Newcastle, New South Wales, Australia
    Med Phys 34:3815-24. 2007
    ..The response change is unlikely to be significant for clinical IMRT verification with this imaging/acclerator system where MUs are of the order of 100-300, provided the detector does not exhibit radiation damage artifacts...
  5. ncbi Investigation of an amorphous silicon EPID for measurement and quality assurance of enhanced dynamic wedge
    Peter B Greer
    Radiation Oncology Department, Newcastle Mater Hospital, and Physics and Mathematical Physics, University of Newcastle, Newcastle, New South Wales 2298, Australia
    Phys Med Biol 52:1075-87. 2007
    ..Due to the ease of use and reproducibility of the EPID-measured EDW profiles the device is highly suited to regular measurement of EDW...
  6. ncbi An energy fluence-convolution model for amorphous silicon EPID dose prediction
    Peter B Greer
    Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Locked Bag 7, Hunter Region Mail Centre, Newcastle, NSW 2310, Australia
    Med Phys 36:547-55. 2009
    ..Removing the backscatter component of the pixel sensitivity matrix correction reduces the effect of nonuniform E-arm backscatter...
  7. ncbi Correction of pixel sensitivity variation and off-axis response for amorphous silicon EPID dosimetry
    Peter B Greer
    Newcastle Mater Hospital, and University of Newcastle, Newcastle, New South Wales, Australia
    Med Phys 32:3558-68. 2005
    ..The new correction method gives consistent dosimetry for any EPID position and retains beam profile information in the image...
  8. ncbi Improving the resolution of dynamic intensity modulated radiation therapy delivery by reducing the multileaf collimator sampling distance
    Peter B Greer
    B C Cancer Agency, Vancouver Island Center, Victoria, B C, Canada
    Med Phys 30:2793-803. 2003
    ..0 cm leaf width at a sampling distance of 0.5 cm, with only a small benefit for further reduction. For the 0.5 cm leaf width, a sampling distance of 0.25 cm resulted in a dose resolution that was nearly independent of direction...
  9. ncbi The effect of leaf width and sampling distance on the "stair-stepping" of field borders defined by multileaf collimators
    P B Greer
    Department of Medical Physics, BC Cancer Agency, Vancouver Island Centre, Victoria, V8R 6V5, Canada
    Australas Phys Eng Sci Med 26:45-52. 2003
    ..5 cm leaf width compared to a 1.0 cm leaf width. Reducing the sampling distance for the 1.0 cm MLC leaf can approximate the 0.5 cm leaf width, at the expense of longer treatment times, and increased quality assurance investment...
  10. ncbi Dosimetric properties of an amorphous silicon electronic portal imaging device for verification of dynamic intensity modulated radiation therapy
    Peter B Greer
    Department of Medical Physics, B C Cancer Agency, Vancouver Island Centre, 2410 Lee Avenue, Victoria V8R 6V5, Canada
    Med Phys 30:1618-27. 2003
    ..The EPID shows promise as a device for verification of IMRT, the major limitation currently being due to dead-time in frame acquisition...
  11. ncbi Evaluation of an a-Si EPID in direct detection configuration as a water-equivalent dosimeter for transit dosimetry
    Mahsheed Sabet
    School of Mathematical and Physical Sciences, Faculty of Science and IT Callaghan Campus, University of Newcastle, Newcastle, New South Wales 2308, Australia
    Med Phys 37:1459-67. 2010
    ....
  12. ncbi Experience converting an RT department to full CT simulation: technical issues identified during commissioning of a wide-bore scanner
    M A Ebert
    Department of Radiation Oncology, Sir Charles Gairdner Hospital, Hospital Avenue, Nedlands, Western Australia 6009, Australia
    J Med Imaging Radiat Oncol 53:325-30. 2009
    ..Departments should be mindful of these issues when using a GE Lightspeed wide-bore scanner and should consider how scanner settings should be optimised for the use of images in treatment planning...
  13. ncbi CT-ED conversion on a GE Lightspeed-RT scanner: influence of scanner settings
    M A Ebert
    Department of Radiation Oncology, Sir Charles Gairdner Hospital, Nedlands, Australia
    Australas Phys Eng Sci Med 31:154-9. 2008
    ....
  14. ncbi Software tool for portal dosimetry research
    P Vial
    Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
    Australas Phys Eng Sci Med 31:216-22. 2008
    ..The operation of the software tool was validated. This software provided useful tools for EPID dosimetry research, and it is being utilised and further developed in ongoing EPID dosimetry and IMRT dosimetry projects...
  15. ncbi Evaluation of an algorithm for the assessment of the MTF using an edge method
    P B Greer
    Department of Medical Physics, Royal Adelaide Hospital, Australia
    Med Phys 27:2048-59. 2000
    ..The MTF calculation algorithm and the transfer function analysis have been incorporated into a Windows-based software program to be made available for general use...
  16. ncbi Initial evaluation of a commercial EPID modified to a novel direct-detection configuration for radiotherapy dosimetry
    Philip Vial
    Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres, Sydney 2170, Australia
    Med Phys 35:4362-74. 2008
    ..The modified DD-EPID configuration studied here has the potential to improve the performance of EPIDs for dose verification of radiotherapy treatments...
  17. ncbi Measurement and modeling of the effect of support arm backscatter on dosimetry with a varian EPID
    Pejman Rowshanfarzad
    School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, New South Wales 2308, Australia
    Med Phys 37:2269-78. 2010
    ..In this study, a method has been described to quantify, model and correct for the effect of backscattered radiation from the EPID support arm (E-Arm type, Varian Medical Systems)...
  18. ncbi An EPID based method for efficient and precise asymmetric jaw alignment quality assurance
    Luke Clews
    Calvary Mater Newcastle Hospital, Newcastle, New South Wales, 2298, Australia
    Med Phys 36:5488-96. 2009
    ..The aim of this work was to investigate the use of amorphous silicon electronic portal imaging devices (EPIDs) for regular quality assurance of linear accelerator asymmetric jaw junctioning...
  19. ncbi Direct-detection EPID dosimetry: investigation of a potential clinical configuration for IMRT verification
    Philip Vial
    Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centre, NSW, 2170, Australia
    Phys Med Biol 54:7151-69. 2009
    ..The dEPID is a water-equivalent dosimeter that can be implemented with minimal modifications to the standard commercial EPID design. The proposed dEPID design greatly simplifies the verification of IMRT dose delivery...
  20. ncbi Correction of systematic setup errors in prostate radiation therapy: how many images to perform?
    Joanna J S Ludbrook
    Radiation Therapy Program, British Columbia Cancer Agency, Vancouver Island Centre, Victoria, BC, Canada
    Med Dosim 30:76-84. 2005
    ..A small tolerance level should be utilized with 2 mm giving good accuracy with minimal unnecessary shifts...
  21. ncbi Cone beam computerized tomography: the effect of calibration of the Hounsfield unit number to electron density on dose calculation accuracy for adaptive radiation therapy
    Joan Hatton
    Radiation Oncology Department, Calvary Mater Newcastle, NSW, Australia
    Phys Med Biol 54:N329-46. 2009
    ..More importantly, the amount of scattering material used with the HU to ED calibration phantom has a significant effect on the dosimetric accuracy, particularly in the radial direction...
  22. ncbi A simple approach to using an amorphous silicon EPID to verify IMRT planar dose maps
    Christopher Lee
    Central Coast Radiation Oncology Centre, Gosford, New South Wales, 2250, Australia
    Med Phys 36:984-92. 2009
    ..Based on the range of fields studied, the author's results appear to justify using this approach as a method to verify dose distributions calculated on a treatment planning system, including complex intensity modulated fields...
  23. ncbi An experimental investigation into the radiation field offset of a dynamic multileaf collimator
    Philip Vial
    Northern Sydney Cancer Centre, Radiation Oncology, Royal North Shore Hospital, NSW 2065, Australia
    Phys Med Biol 51:5517-38. 2006
    ..We propose a methodology for measuring and implementing MLC leaf offsets that is suitable for both SMLC and DMLC IMRT. In addition, we propose some definitions that more clearly describe the MLC leaf position for accurate IMRT dosimetry...
  24. ncbi The impact of MLC transmitted radiation on EPID dosimetry for dynamic MLC beams
    Philip Vial
    Royal North Shore Hospital, Institute of Medical Physics, School of Physics, University of Sydney, Sydney, Australia
    Med Phys 35:1267-77. 2008
    ..Further investigation into the detector response function and the radiation source model are required to achieve improvements in accuracy for the general case...
  25. ncbi A design for a dual assembly multileaf collimator
    P B Greer
    Department of Medical Physics, Royal Adelaide Hospital, University of Adelaide, Australia
    Med Phys 27:2242-55. 2000
    ..The shielding of this design was found to be adequate provided the leaf faces of the adjacent vertically displaced leaves are at least aligned, therefore an overlap or tongue and groove is not required...
  26. ncbi Long-term two-dimensional pixel stability of EPIDs used for regular linear accelerator quality assurance
    B W King
    School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, NSW 2308, Australia
    Australas Phys Eng Sci Med 34:459-66. 2011
    ..Since the EPID response was found to be very stable over long periods of time, an annual calibration should be sufficient in most cases. More complex dosimetric calibrations should be clinically feasible...
  27. ncbi Measuring time to biochemical failure in the TROG 96.01 trial: when should the clock start ticking?
    James W Denham
    School of Medicine and Public Health, University of Newcastle, New South Wales, Australia
    Int J Radiat Oncol Biol Phys 75:1008-12. 2009
    ..We sought to determine whether short-term neoadjuvant androgen deprivation (STAD) duration influences the optimal time point from which Phoenix fail (time to biochemical failure; TTBF) should be measured...
  28. ncbi Recognizing false biochemical failure calls after radiation with or without neo-adjuvant androgen deprivation for prostate cancer
    James W Denham
    University of Newcastle, New South Wales, Australia
    Int J Radiat Oncol Biol Phys 74:404-11. 2009
    ..We studied prostate-specific antigen (PSA) changes after radiation with or without neoadjuvant androgen deprivation to determine posttreatment PSA scenarios in which false-positive biochemical failures (FPBF) are most likely to occur...
  29. ncbi Time to biochemical failure and prostate-specific antigen doubling time as surrogates for prostate cancer-specific mortality: evidence from the TROG 96.01 randomised controlled trial
    James W Denham
    School of Medicine and Public Health, University of Newcastle, Newcastle, NSW, Australia
    Lancet Oncol 9:1058-68. 2008
    ..We sought to assess time to biochemical failure (TTBF) and prostate-specific antigen doubling time (PSADT) after failure of curative treatment as candidates for this endpoint...