MR Imaging Based Treatment Planning for Radiotherapy of Prostate Cancer
Annual rept. 1 Feb 2005-31 Jan 2006
FOX CHASE CANCER CENTER PHILADELPHIA PA
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This work is aimed at MRI-based treatment planning for radiation therapy. The tasks for the second year include a Evaluate MRI-based prostate treatment planning dose calculation b Develop practical methods for heterogeneity correction for MR-based dose calculation and c Implement and validate a MRI-based Monte Carlo dose verification system for IMRT QA. We have quantified the residual distortions and developed computer software to reduce them using point-by point corrections for large patients lateral dimension up to 42 cm. We have verified dosimetric accuracy and consistency for MR based IMRT treatment planning for prostate cancer using the Monte Carlo method. Our results showed that for IMRT treatments with coplanar beam arrangements, the mean dose values of the CTV for homogeneous geometry based on CT were about 2 higher than those for heterogeneous geometry based on CT. The difference in the mean CTV dose between homogenous MRI and heterogeneous CT geometries was about 3 and less. We have also studied heterogeneity corrections for patients with hip replacements prostheses.
- Medicine and Medical Research