Cynthia Chuang

Cynthia Fu-Yu Chuang, Ph.D.

Associate Professor
Division of Physics
Department of Radiation Oncology

UCSF Medical Center at Mission Bay
1825 4th Street, M2260
San Francisco, CA 94158
Phone: (415) 353-8659

Make A Gift Button

Professional Focus


Dr. Chuang is a certified medical physicist with 15 years of clinical experience. She was the main physicist for the CyberKnife stereotactic radiotherapy program at UCSF for more than 7 years. Over the past 3 years, she was the lead physicist to coordinate the installation, conduct radiation survey, commission and finish the Eclipse treatment planning verification for two new Varian TrueBeam linear accelerators. She also commissioned the cone based iPlan treatment planning system for SRS. In addition to routine quality assurance tasks and chart checks, her duties include creating quality assurance procedures, establishing and implementing clinical workflow for SRS/SBRT on the TrueBeam STx, and now will extend to include implementing Gating and gated SBRT at Mission Bay TrueBeam.


Dr. Chuang is an independent researcher with 1 patent, and more than 40 peer-reviewed papers and book chapters. She is interested in the integration of better tumor visualization/delineation and better treatment delivery quality assurance for Adaptive Radiation Therapy, which includes Intensity Modulated Radiation Therapy (IMRT), Image-Guided Precision Radiation Therapy, and Stereotactic Body Radiosurgery/Radiotherapy (SBRT).

For the past 3 years, one of her research interests has been to quantify the accuracy of deformable image registration (DIR), which is needed for accurate dose accumulation for adaptive RT. The patent was awarded for the design and creation of a physical phantom that will allow quantitative verification of DIR. She worked closely with one of our previous medical physics residents to design a second-generation deformable measurement phantom with known deformation, which can be used to quantify the accuracy of deformable image registration algorithms. She also worked with another physics resident on utilizing ImSim QA, a software that can create deformed images with known deformation matrices, to be used to independently validate the accuracy of the commercial deformation algorithms.

One of her research interests currently is focusing on getting more frequent and better on-line imaging during treatments, and utilizing those data for adaptive radiation treatment planning for the new Varian True Beam at Mission Bay. To be sure that these imaging data are accurate, more frequent imaging QA is needed to ensure that the imagers are functioning correctly and at their optimal performance level. Last year, her research group created automatic image acquisition sequences and imager positioning accuracy analysis scripts to be used on the TrueBeam. They also developed automatic image artifacts detection algorithms based on machine learning. They hope that by using these procedures, they can make imager QA much more accurate, efficient and thorough, and enabling the physicists to perform the QA more frequently to assure the quality of IGRT delivery.

The installation of the new TrueBeam at Mission Bay opens the possibility of patients being treated there for liver and pancreatic tumors using gated stereotactic body radiotherapy. So one of her new research directions will be to investigate the feasible workflow and delivery precision for gated SBRT. The group will be studying the feasibility of using on-line EPID and transit dosimetry to ensure that each patient receives the dose that was planned. This is of particular importance as we are going forward to implement gated SBRT.


1986-1990 Massachusetts Institute of Technology, Cambridge, MA BS Electrical Engineering
1990-1992 University of Pennsylvania, Philadelphia, PA MS Bioengineering
1992-1994 Massachusetts Institute of Technology, Cambridge, MA MS Nuclear Engineering
1994-1999 Massachusetts Institute of Technology, Cambridge, MA PhD Nuclear Engineering
1999-2001 Lawrence Livermore National Laboratory, Livermore, CA Post-Doctoral Research Fellow Peregrine Project
1999-2002 University of California San Francisco, San Francisco, CA Medical Physics Resident Department of Radiation Oncology


06/2006 Therapeutic Physics. American Board of Radiology

Professional Experience

06/13-present UCSF Associate Professor Radiation Oncology
07/09-06/13 UCSF Assistant Professor in Residence Radiation Oncology
07/05-06/09 UCSF Assistant Adjunct Professor Radiation Oncology
10/02-06/05 UCSF Clinical Instructor Radiation Oncology

Awards & Honors

1998 The Fairchild Award for Young Researchers, International Society for Neutron Capture Therapy
2004 AAPM Travel Grant Award, The American Association of Physicists in Medicine


Recent Significant Publications :

G. Valdes, O. Morin, J. Pouliot, C. Chuang, "Use of the TrueBeam Developer Mode for Imaging QA", Journal of Applied Clinical Medical Physics, 16 (4), pg. 322-333, 2015

K. Nie, C. Chuang, N. Kirby, S. Braunstein, J Pouliot, "Site-Specific Deformable Imaging Registration (DIR) Algorithm Selection using Patient-Based Simulated Deformations", Medical Physics, 40 (4): 041911, 2013

N. Kirby, C. Chuang, U. Ueda, J. Pouliot, “The Need for Application-Based Adaptation of Deformable Image Registration”, Medical Physics, 40 (1): 011702 (10 pages), 2013

M. Dayal, A. Perez-Andujar, C. Chuang, A. T. Parsa, I.J. Barani, “Management of Vestibular Schwannoma: Focus on Vertigo”, CNS Oncology, 2(1): 99-104, 2013

J. M Lupo, C. F. Chuang, S. M. Chang, I. J. Barani, B. Jimenez, C. P. Hess, S. J. Nelson, “7_Tesla Susceptibility-Weighted Imaging to Assess the Effects of Radiotherapy on Normal-Appearing Brain in Patients with Glioma”, Int. J. of Rad. Oncol. Biol. Phys., 82 (3): 493-500, 2012

M. Descovich, L. Ma, C. F. Chuang, D. A. Larson, I. J. Barani, “Comparison Between Prone and Supine Patient Setup for Spine Stereotactic Body Radiosurgery”, Technology in Cancer Research & Treatment. 11 (3): 229-236, 2012

S. Jabbari, V.K. Weinberg, T. Kaprealian, I.C. Hsu, L. Ma, C. Chuang, M. Descovich, S. Shiao, K. Shinohara, M. Roach, A. R. Gottschalk, "Stereotactic Body Radiotherapy (SBRT) as Monotherapy or Post-External Beam Radiotherapy (EBRT)-Boost for Prostate Cancer (PCa): Technique, Early Toxicity, and PSA Response," Int. J. of Rad. Oncol. Biol. Phys., 82 (1): 228-234, 2012.

N. Kirby, C. Chuang, J. Pouliot, A. Hwang, I. J. Barani, "Physics Strategies for Sparing of Neural Stem Cells During Whole-brain Radiation Treatments" Medical Physics, 38 (10): 5338-5344, 2011

N. Kirby, C. Chuang, J. Pouliot, "A Two-Dimensional Deformable Phantom for Quantitatively Verifying Deformation Algorithms", Medical Physics, 38 (8): 4583-4586, 2011

S. Dieterich, C. Cavedon, C. F. Chuang, A. B. Cohen, J. A. Garrett, C. L. Lee, J. R. Lowenstein, M. F. d'Souza, D. D. Taylor, X. Wu, C. Yu, "Quality Assurance for Robotic Radiosurgery, TG135 report," Medical Physics, 38 (6): 2914-2936, 2011