Woodruff School of Mechanical Engineering

NRE 8011/8012 and MP 6011/6012 Seminar

Nuclear & Radiological Engineering and Medical Physics Programs


VMAT-Treatment Technique and 3D Rotational Verification QA Methods


Dr. Anees H. Dhabaan


Emory University School of Medicine


Thursday, February 4, 2010 at 11:00:00 AM


Boggs Building, Room 3-47, 3rd FL


Farzad Rahnema


Advances in radiotherapy have played a pivotal role in improving the long term survival of cancer patients and improving the quality of life. One of these recent advances is the development of Volumetric Modulated Arc Therapy (VMAT) for external beam radiotherapy. VMAT is a an extension of intensity modulated radiation therapy (IMRT) that delivers optimized three-dimensional dose distributions with a single gantry rotation rather than the multiple fields required for standard IMRT techniques. Compared to IMRT total monitor units (MUs) for VMAT plans are significantly less than for IMRT plans. Thus, VMAT reduces total treatment times significantly, and it will also lead to less intra fraction patient movements. Furthermore, a recent study at our department utilizing TLD measurements in a pediatric phantom showed that a VMAT procedure would reduce radiation dose outside of the target volume compared to IMRT techniques without compromising target conformity. This may play a pivotal role in improving the long term survival of patients by reducing the long-term side effects of treatment including the development of secondary malignancies. The delivery accuracy of each treatment plan is vital. Therefore, plan verification QA is very important for the success of the VMAT treatments. While current 2D dosimetric systems provide adequate information about the accuracy of dose delivered, they lack the geometric/volumetric details. Our research group has been evaluating an online 3D Dosimetry system (Compass) for treatment plan verification which provides indirectly measured dose details for PTV and OAR. This presentation will discuss the VMAT treatment technique and QA measurements used in our research program. Clinical case examples will also be described using VMAT techniques.


Dr. Anees Dhabaan is an Assistant Professor at the department of radiation Oncology, Emory University School of Medicine. Dr. Dhabaan is implementing new technology such as Rapid ARC and Novalis TX in the stereotactic radiosurgery program. His postgraduate research has included in designing a blanket for nuclear fusion reactor which entailed work in the area of neutron and photon transport and the use of Monte Carlo method in tracking these particles. As a medical physicist, he worked in various areas in the past such as developing a numerical algorithm that simulates charged particle transport (proton and electron) in a dense media. His research interest is simulating charged particle transport in dense media using Monte Carlo Codes. His research focus on image guided radiation therapy. He received his Ph.D. in Physics from University of Birmingham, England, U.K. He received his Masters in Medical Physics from Emory University. He received his certification in 2003 from American Board of Radiology in Therapeutic Radiological Physics. He also obtained his M.Sc. in Nuclear Reactor Science and Engineering, University of London, England and a B.Sc. in Nuclear Engineering, University of Baghdad.


Refreshments will be served.