Automated Patient Positioning Guided by Cone-Beam CT for Prostate Radiotherapy
Abstract
Modern radiotherapy equipment is capable of delivering high precision conformal dose distributions to the target. However, the target localization especially for soft-tissue target such as prostate is an issue, because of its possible non-rigid internal motion relative to bony structures or external landmarks. Recently, a new technology of kilo-voltage cone-beam CT (CBCT) has been integrated with the linear accelerator treatment machine. Superior to the common approach based on the two orthogonal images provided by the mega-voltage EPID, CBCT can provide high-resolution three-dimensional (3D) information of the patient in the treatment position. Thus the target localization could be potentially done more accurately without using any implanted fiducials. In practice, however, there is currently still a general lack of efficient method to utilize the 3D CBCT images. In this work, we have developed a clinically practical technique for automatic patient positioning based on the newly emerged CBCT, accounting for the non-rigid motions of the prostate and surrounding structures. A novel deformable registration method has also been developed to improve the positioning accuracy. Furthermore, a low-dose CBCT acquisition protocol is being developed so that a daily use of CBCT becomes possible for prostate patients.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2007
- Accession Number
- ADA466162
Entities
People
- Tianfang Li
Organizations
- Stanford University