Abstract
A non‐film‐based system was used to obtain high quality portal film images. Digital portal images were obtained with a computed radiography (CR) system, in which the film is replaced with a photostimulable phosphor plate. Digital processing of portal images enhanced the display contrast using regional histogram equalization. The images were compared to images on radiographic film, exposed in the same cassette. The contrast‐enhanced CR images of prostate treatment fields facilitated identification of the entire contour of the ischium, the location of the pubic symphysis, and the ischial tuberosity to determine the anterior and inferior locations of the prostate and bladder. Identifying the coccyx on the processed portal images permits the physician to locate accurately the posterior wall of the rectum. In each case the quality of the CR image was judged by the clinician to be superior to conventional portal film. The identification of these anatomical structures on the portal images is clinically important for verifying 3D conformal therapy of the prostate. With the same CR system one may acquire digital treatment portal and simulation images. This provides a foundation for a picture archival communication system for radiation oncology. Existing software can be used to register these digital portal and simulation images to facilitate verification of treatment setup.PACS number(s): 87.53.–j, 87.57. –s
Highlights
Recent advances in radiation oncology, including the development of computerized tomographyCTsimulators, three-dimensional treatment planning systems, stereotactic frames, and intensitymodulated radiation permit the use of more complex, noncoplanar methods to treat tumors with higher doses and tighter margins
Digital portal images were obtained with a computed radiographyCRsystem, in which the film is replaced with a photostimulable phosphor plate
The images obtained of the treatment portal fields are important for verification of both the precision and accuracy of treatment delivery
Summary
Recent advances in radiation oncology, including the development of computerized tomographyCTsimulators, three-dimensional treatment planning systems, stereotactic frames, and intensitymodulated radiation permit the use of more complex, noncoplanar methods to treat tumors with higher doses and tighter margins. This is intended to increase local control in the treatment of a number of tumors. Verification of the treatment set-up fields is more complicated requiring beams-eye view projections of the internal anatomy that are reconstructed from axial CT studies. The reduced planning-target volumes required to spare normal tissues and the tighter definition of tumor margins makes the accuracy of the treatment setup more critical.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
