This is a proposal for a Port Digital Imager (PDI). The PDI is a monolithic, solid state, detector array substitute for port film. Because the solid state electronics digitize the image, imaging software can be used in conjunction with the PDI to immediately enhance the image contrast. An evaluation of beam position with respect to boney landmarks and simulator treatment plan is, therefore, possible, on line, in real time, while the patient is still on the treatment table. Localization errors can, therefore, be avoided. The instrument will increase the effectiveness of radiation therapy and help prevent treatment injuries. The technical objective of the Phase I effort is the detailed design and computer simulation, performance verification of the Port Digital Imager. PDI hardware and image formation will be computer simulated in Phase I. The technical objective of Phase II is the fabrication of a prototype PDI with imaging processing software. Anthoprometric phantom experiments will be performed using UCLA therapeutic x-ray equipment to determine instrument performance and refine image processing. Potential for PDI commercial application is high. Research clearly demonstrates that localization errors decrease with increased use of port films and a well-defined need for a convenient, fast, high contrast, port imaging method is recognized by the Radiotherapy community.
