Quality assurance for nonradiographic radiotherapy localization and positioning systems: Report of Task Group 147

Abstract

New technologies continue to be developed to improve the practice of radiation therapy. As several of these technologies have been implemented clinically, the Therapy Committee and the Quality Assurance and Outcomes Improvement Subcommittee of the American Association of Physicists in Medicine commissioned Task Group 147 to review the current nonradiographic technologies used for localization and tracking in radiotherapy. The specific charge of this task group was to make recommendations about the use of nonradiographic methods of localization, specifically; radiofrequency, infrared, laser, and video based patient localization and monitoring systems. The charge of this task group was to review the current use of these technologies and to write quality assurance guidelines for the use of these technologies in the clinical setting. Recommendations include testing of equipment for initial installation as well as ongoing quality assurance. As the equipment included in this task group continues to evolve, both in the type and sophistication of technology and in level of integration with treatment devices, some of the details of how one would conduct such testing will also continue to evolve. This task group, therefore, is focused on providing recommendations on the use of this equipment rather than on the equipment itself, and should be adaptable to each user's situation in helping develop a comprehensive quality assurance program.

Quality assurance for the clinical implementation of kilovoltage intrafraction monitoring for prostate cancer VMAT

“…The proposed test frequency is based on TG 147 recommendations. 17 Although TG 147 is based on nonradiographic systems, it encompasses the QA of a real-time localization modality which can be applied other real-time methods.…”

“…16) and 147. 17 The four important differences between KIM and Calypso which require adapting Santanam's approach are (1) KIM delivers kV dose to the patient while Calypso does not, (2) KIM only monitors the prostate position when the kV beam is activated while Calypso continuously monitors the prostate position, (3) KIM does not require additional equipment (assuming KIM is implemented on a Linac with an existing gantry-mounted kV imager), and (4) KIM does not require a dedicated couch.…”

Accuracy and efficiency of an infrared based positioning and tracking system for patient set-up and monitoring in image guided radiotherapy

“…The AAPM (American Association of Physicists in Medicine) Task Group 147 [8] has reviewed the current technologies specifically used for non-radiographic localization and tracking of the patient in radiotherapy. Based on some of the recommendations from this report, we have tested the characteristics of IPT system including spatial drift, positioning reproducibility as well as static and dynamic localization accuracy.…”

Direct aperture optimization using an inverse form of back‐projection

“…Algorithms for IMRT leaf sequencing have been developed and improved to reduce total segment numbers in order to shorten treatment delivery time 1 , 2 , 3 , 4 . Recent studies indicate that shortening treatment time could reduce dose delivery uncertainty due to organ motion and patient setup for image‐guided radiotherapy, adaptive radiotherapy, and radiotherapy quality assurance 5 , 6 , 7 , 8 . In addition to dosimetric quality, the workflow efficiency of the cancer clinic is also affected by long treatment time.…”