Τίτλος:
Dose verification in clinical imrt prostate incidents
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Purpose In view of the need for dose-validation procedures on each individual intensity-modulated radiation therapy (IMRT) plan, dose-verification measurements by film, by ionization chamber, and by polymer gel-MRI dosimetry were performed for a prostate-treatment plan configuration. Treatment planning system (TPS) calculations were evaluated against dose measurements. Methods and materials Intensity-modulated radiation therapy (IMRT) treatments were planned on a commercial TPS. Kodak EDR-2 films were used for the verification of two-dimensional (2D) dose distributions at 1 coronal and 5 axial planes in a water-equivalent phantom. Full three-dimensional (3D) dose distributions were measured by use of a novel polymer gel formulation and a 3D magnetic resonance imaging (MRI) readout technique. Calculations were compared against measurements by means of isocontour maps, γ-index maps (3% dose difference, 3-mm distance to agreement) and dose-volume histograms. Results A good agreement was found between film measurements and TPS predictions for points within the 60% isocontour, for all the examined plans (γ-index <1 for 96% of pixels). Three-dimensional dose distributions obtained with the polymer gel-MRI method were adequately matched with corresponding TPS calculations, for measurements in a gel phantom covering the planning-target volume (PTV). Conclusions Measured 2D and 3D dose distributions suggest that, for the investigated prostate IMRT plan configuration, TPS calculations provide clinically acceptable accuracy. © 2004 Elsevier Inc.
Συγγραφείς:
Sandilos, P.
Angelopoulos, A.
Baras, P.
Dardoufas, K.
Karaiskos, P.
Kipouros, P.
Kozicki, M.
Rosiak, J.M.
Sakelliou, L.
Seimenis, I.
Vlahos, L.
Περιοδικό:
International Journal of Radiation, Oncology, Biology, Physics
Λέξεις-κλειδιά:
Intensity modulated radiation therapy (IMRT); Polymer gels, Disease control; Dosimetry; Gels; Ionization chambers; Magnetic resonance imaging, Radiotherapy, polymer, article; film dosimeter; gel; histogram; human; intensity modulated radiation therapy; ionization chamber; male; mathematical computing; measurement; medical instrumentation; nuclear magnetic resonance imaging; priority journal; prostate cancer; radiation dose; radiation dose distribution; three dimensional imaging; treatment planning; validation process, Humans; Male; Phantoms, Imaging; Radiometry; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Conformal
DOI:
10.1016/j.ijrobp.2004.04.029
