A number of publications have appeared in the scientific literature relating to PIPSpro and/or the QC-3 phantom. For a list of some of these publications click here

PIPS was developed at the Manitoba Cancer Treatment and Research Foundation (MCTRF) during the period 1993-1997. The scientific concepts used in PIPS are based in part on the published research work carried out by Shlomo Shalev and colleagues in the Precision Radiotherapy research group at MCTRF during the period 1985-1997. This research involved portal imaging, image processing, quality control, and treatment planning, and the results were published in technical journals, scientific conference proceedings, and as abstracts of presentations at national and international conferences. A brief non-technical summary of these research topics is given here for the general reader, and links are provided to lists of publications by the group for further reading. See also Dr. Shlomo Shalev's bibliography at the University of Manitoba website for on-line abstracts of most of these publications.

Electronic portal imaging.

Treatment of cancer by high energy radiation ("megavoltage radiation therapy") can be successful only if the treatments are delivered with exceptionally high accuracy. One of the ways to verify that the treatment is correct is to acquire images, called portal images, during the actual treatment session, using the high energy radiation beams passing through the body of the patient. The Precision Radiotherapy group was involved in the design, construction, and clinical application of electronic portal imaging devices (EPIDs) for this purpose. This work was mainly involved with fluoroscopic EPIDs, the optimization of cameras and metal/phosphor screens, and the acquisition and digitization of video images. For a selective list of our publications on these topics click here

Image processing.

Megavoltage portal images have inherently poor spatial and contrast resolution. The Precision Radiotherapy group was involved in the development of algorithms for the enhancement of portal images and for the determination of treatment field size, shape and position. It is very important that the enhancement does not change the field edge, since this is used for measurements of field displacements. Various techniques were developed for image registration, and for the display of field placement errors both quantitatively and visually using images of regret. A comprehensive set of image processing algorithms has been incorporated into the PIPS package for easy application even by computer-wary personnel. For a partial list of our publications on these topics click here

Quality Control.

Electronic portal imaging can be useful in the clinic only if the images are of sufficient quality to clearly show anatomical features. However, electronic portal imaging devices cannot easily be adjusted to give optimal image quality, nor were there any quantitative tests for checking image quality on a regular basis. The Precision Radiotherapy group developed a test phantom for this purpose, and used it to investigate the image quality from numerous EPIDs in cancer treatment centers around the world. For a partial list of our publications on this topic click here

Treatment planning.

Planning a course of megavoltage radiation therapy is a complex proceedure, involving the careful consideration of both physical and biological parameters. The Precision Radiotherapy group was involved in the development of mathematical techniques which permit the optimization of treatment plans, using clinical prescriptions of radiation dosage and balancing the curative effect of the radiation on the tumor and its harmful effect on normal tissues. With the advent of electronic portal imaging, more information is becoming available on the limitations of setup accuracy, and techniques were investigated for incorporating these data into the planning process. For a partial list of our publications on this topic click here