Optimization of Breast Cancer Treatment by Dynamic Intensity Modulated Electron Radiotherapy
Abstract
Three specific work projects were pursued during the first year of this grant: 1) Static electron fields defined by the photon MLC were measured. Beam profiles and output factors at distances of 75, 85 and 100 cm SSD were measured for fields from 1 cm to 20 cm wide. Measurements were made for electron energies of 6, 9, 12, 16 and 20 MeV. Profiles were compared vs. energy, and their departure from strictly divergent fields was noted. Profiles defined by the MLC were compared with previous profiles defined by cerrobend(Trademark) apertures. 2) Monte Carlo techniques were applied to 3D electron dose calculations. The rounded shape of the MLC ends, the long air scatter column, and the reduced density air at Utah altitude were addressed in the calculations. Excellent agreement was achieved compared to measured profiles and.measured relative output factors. The Monte Carlo calculations correctly account for air scatter effects vs. field size and SSD, and correctly predict relative output factors vs. field size and SSD. 3) An iterative optimization technique to determine the required MLC leaf positions vs. arc rotation was defined. The work to date is on track for successful completion of the project within the grant period.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2002
- Accession Number
- ADA412101
Entities
People
- David K. Gaffney
- Dennis D. Leavitt
Organizations
- University of Utah