Click here to


Are you sure ?

Yes, do it No, cancel

Present and Future of IMRT QA

B Hasson1*, J Carroll2*, J Park3*, M Miften4*, (1) Anne Arundel Medical Center, Annapolis, MD, (2) Versant Medical Physics & Radiation Safety, Tewksbury, MA, (3) University of Florida, Gainesville, FL, (4) University of Colorado School of Medicine, Aurora, CO


(Monday, 4/1/2019) 10:30 AM - 12:30 PM

Room: Osceola Ballroom C

To provide attendees with an understanding of present IMRT QA practices and tools, overview of patient specific QA considering Task Group 218 recommendations, logfile/electronic IMRT QA, and insights into research efforts of the future of patient Specific IMRT QA.

A main cornerstone in Clinical Medical Physics is conducting quality assurance measures to insure accurate and reliable treatments. The field of Medical Physics is a dynamically changing field that requires continual evolution of the processes and methods to deliver the highest quality care. The introduction and clinical implementation of Intensity Modulated Radiation Therapy (IMRT) in the 1990’s created a paradigm shift in radiation therapy1. However, the QA processes for a dynamic treatment delivery had not been developed. In 1994 TG-40 was introduced to update the existing QA standards that were in place since 19842,3. Though TG-40 was comprehensive, it did not address the quality assurance for MLC or dynamic treatment deliveries. In 2001, TG-50 introduced concepts for quality assurance measures with MLC’s4. The first AAPM report that specifically addressed IMRT quality assurance was 082 published in 2003, and the authors stated, “IMRT was one of the most significant technical advances in Radiation Therapy�5. The first report to highlight specific QA measures for IMRT based delivery machines was TG-1426. TG-218, published in 2018, addresses the tolerance limits and measurement methods for IMRT/VMAT QA6. TG-218 provides guidance for the Medical Physicist, and a solid basis for standardization of IMRT QA across institutions. However, TG-218 does not provide recommendations or tolerance limits for electronic (logfile) based QA. This session will provide an understanding of the evolution of IMRT and VMAT QA techniques, and highlight the importance of the Medical Physicist role in advancing technologies while providing the QA measures to insure accurate and reliable treatments in the future.

Learning Objectives:
1. Recognize characteristics of IMRT specific phantoms and detectors.
2. The difference in measurement techniques for IMRT QA and recommendations from TG-218.
3. Specific QA measures associated with IMRT QA.
4. IMRT QA processes and limitations of portal imagers.
5. Logfiles to compliment or possibly replace measurement based IMRT QA.


Contact Email