Development of Novel Treatment Plan Verification Techniques for Prostate Intensity Modulation Arc Therapy
Abstract
For fractionated treatment, adaptive radiation therapy (ART) is a strategy of which the subsequent fractional delivery can be adaptively modified based on a closed-loop control framework using systematic feedback of geometric and dosimetric information. However, a critical component that is missing in current linac-based radiation therapy is a treatment plan verification system capable of validating and documenting the dose delivered and preventing geographic misses, especially for modern volumetric intensity modulated arc therapy (VMAT). The objective of this project is to develop a novel clinical useful delivered-dose verification protocol for modern prostate VMAT using Electronic Portal Imaging Device (EPID) and onboard Cone beam Computed Tomography (CBCT). We have carried a systematic study on developing the CBCT and EPID imaging based dose verification technique. A number of important milestones have been accomplished, which include (i) calibrated CBCT HU vs. electron density curve; (ii) established technical infrastructures for deformable registration between CBCT and pCT and detecting MLC leaf end positions using EPID images acquired during treatment; (iii) developed a gantry and imager geometric calibration procedure; (iv) developed an intrafraction prostate motion monitoring and correction strategy and a dose reconstruction technique for treatment plan verification; and (v) performed phantom studies using the developed techniques.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2010
- Accession Number
- ADA526611
Entities
People
- Wu Liu
Organizations
- Stanford University