3D Dose reconstruction: Banding artefacts in cine mode EPID images during VMAT delivery

Cine (continuous) mode images obtained during VMAT delivery are heavily degraded by banding artefacts. We have developed a method to reconstruct the pulse sequence (and hence dose deposited) from open field images. For clinical VMAT fields we have devised a frame averaging strategy that greatly improves image quality and dosimetric information for three-dimensional dose reconstruction.

[1]  E. Schreibmann,et al.  Patient-specific quality assurance method for VMAT treatment delivery. , 2009, Medical physics.

[2]  E. Bezak,et al.  Two-dimensional transmitted dose measurements using a scanning liquid ionization chamber EPID , 2006, Physics in medicine and biology.

[3]  P B Greer,et al.  Dosimetric properties of an amorphous-silicon EPID used in continuous acquisition mode for application to dynamic and arc IMRT. , 2009, Medical physics.

[4]  M van Herk,et al.  Catching errors with in vivo EPID dosimetry. , 2010, Medical physics.

[5]  Frederik Wenz,et al.  Fast kilovoltage/megavoltage (kVMV) breathhold cone-beam CT for image-guided radiotherapy of lung cancer , 2010, Physics in medicine and biology.

[6]  Maarten L P Dirkx,et al.  Fast and accurate leaf verification for dynamic multileaf collimation using an electronic portal imaging device. , 2002, Medical physics.

[7]  M C Kirby,et al.  Verification of dynamic multileaf collimation using an electronic portal imaging device. , 2000, Physics in medicine and biology.

[8]  Peter B. Greer,et al.  An evaluation of cine-mode 3D portal image dosimetry for Volumetric Modulated Arc Therapy , 2010 .

[9]  M. V. van Herk,et al.  Replacing pretreatment verification with in vivo EPID dosimetry for prostate IMRT. , 2007, International journal of radiation oncology, biology, physics.

[10]  P. Lambin,et al.  A literature review of electronic portal imaging for radiotherapy dosimetry. , 2008, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.