Introduction ...........................................................103 IMRT or 3DCRT? ...................................................105 The MSKCC IMRT Planning Process....................107 Patient Selection • Patient Simulation And Structure Localization • Selection Of Beam Energy, Number, And Direction • Optimization • Conversion Of Intensity Profiles To Leaf Motion • Forward Dose ...

A methodology for the dosimetric verification of micro-multileaf collimator MMLC) based intensity modulated radiation therapy (IMRT) plans intended for stereotactic applications is described. The procedure is similar to that of conventional IMRT patient-specific quality assurance with some notable exceptions. Relative dosimetry measurements are performed with radiographic film, a commercial fil...

PURPOSE To compare dose reconstruction accuracy with different oblique beam angles when 2d detector arrays are used for small field IMRT QA. METHODS 2D detector arrays are convenient to use but their low resolution limits the number of sampling points inside small radiation fields. In this study, we demonstrate that with oblique beam incidence, more points can be measured and 3D dose volume c...

Introduction: Electronic portal imaging devices (EPIDs) are extensively used for dosimetric information of pre-treatment field verification and in-vivo dosimetry for Intensity Modulated Radiotherapy (IMRT). In the present work, we have implemented the newly developed portal dosimetry software using independent dose prediction algorithm EPIDose and evaluated this new tool for the pretreatment IM...

To evaluate the utility of Dynalog file information for planar dose verification in IMRT QA, a program is developed to convert Dynalog file data to DMLC field files. For this study, five predefined fluencies are planned and delivered using Varian, Eclipse 3D planning system and 6MV photon beam of Varian, Clinac DMX linear accelerator. To measure planar dose distribution, Kodak, EDR2 films are e...

Agreement between planned and delivered dose distributions for patient-specific quality assurance in routine clinical practice is predominantly assessed utilizing the gamma index method. Several reports, however, fundamentally question current IMRT QA practice due to poor sensitivity and specificity of the standard gamma index implementation. An alternative is to employ dose volume histogram (D...

This study proposes a quality assurance (QA) method incorporating radiobiological factors based on the QUANTEC-determined tumor control probability and the normal tissue complication probability (NTCP) of head-and-neck intensity-modulated radiation therapy (HN-IMRT). Per-beam measurements were conducted for 20 cases using a 2D detector array. Three-dimensional predicted dose distributions withi...

PURPOSE To develop a GPU-based Monte Carlo (MC) 3D dosimetry quality assurance (QA) tool employing patient geometry and actual delivery information. METHODS First, we generate fluence maps at all beam angles from the initial treatment plan. A GPU-based MC dose engine, gDPM, is employed for the secondary dose calculation (SDC) on patient CT. This SDC is used to verify the TPS plan dose (PD) ac...