MagicPlate-512: A 2D silicon detector array for quality assurance of stereotactic motion adaptive radiotherapy

• DOI: 10.1118/1.4921126
• Publication Date: 2015-05-21T20:30:19Z
• Authors: M. Petasecca; M. K. Newall; J. T. Booth; M. Duncan; A. H. Aldosari; I. Fuduli; A. A. Espinoza; C. S. Porumb; S. Guatelli; P. Metcalfe; E. Colvill; D. Cammarano; M. Carolan; B. Oborn; M. L. F. Lerch; V. Perevertaylo; P. J. Keall; A. B. Rosenfeld
• Keywords: Multileaf collimator; Collimator

Purpose: Spatial and temporal resolutions are two of the most important features for quality assurance instrumentation motion adaptive radiotherapy modalities. The goal this work is to characterize performance 2D high spatial resolution monolithic silicon diode array named "MagicPlate-512" stereotactic body radiation therapy (SBRT) radiosurgery (SRS) combined with a dynamic multileaf collimator (MLC) tracking technique compensation. Methods: MagicPlate-512 used in combination movable platform HexaMotion research version radiofrequency system Calypso driving MLC software. authors reconstruct dose distributions small field square beams three modalities: static conditions, mimicking movement pattern lung tumor moving target while compensates almost instantaneously displacement. Use requires proper interference shielding. Impact shielding on dosimetry has been simulated by geant4 verified experimentally. Temporal allow also accurate verification segments complex plans identification instant location where certain delivered. This feature allows retrospective reconstruction delivery process easy error or systems. A sliding wedge measured. ability (MP512) mapping all modes operation was benchmarked EBT3 film. Results: Full width at half maximum penumbra stationary profiles measured film confirm that significant impact distribution. Motion, no motion, agreed within 1 0.4 mm, respectively, sizes tested. electromagnetic generates fluctuation detector baseline up 10% full scale signal requiring strategy. able variation pulse-by-pulse each pixel detector. An analysis transients shows feedback algorithm experiment can compensate effectively only effect slower transient components. fast changing components organ contribute discrepancy order 15% penumbral region change profile 75% expected dose. Conclusions: shown be, potentially, valid alternative ionizing chambers SRS SBRT. Its any conditions motion. It excellent deposition real time retrospectively as function detailed specific area interest.