March 6: Web Site Transition
We have transitioned our web site to the updated version of Google Sites. While some content has been rearranged, the only very significant change is that there is no longer any "sign in" link. All parts of this new site are public. Only the User Forum still requires membership in our User and Development Community (see the Registration link on the navigation menu).
TOPAS wraps and extends the Geant4 Simulation Toolkit to make advanced Monte Carlo simulation of all forms of radiotherapy easier to use for medical physicists. TOPAS can model x-ray and particle therapy treatment heads, model a patient geometry based on CT images, score dose, fluence, etc., save and replay a phase space, provides advanced graphics, and is fully four-dimensional (4D) to handle variations in beam delivery and patient geometry during treatment. TOPAS users configure pre-built components (such as nozzles, patient geometry, dosimetry and imaging components) to simulate a wide variety of radiation therapies with no required knowledge of the underlying Geant4 Simulation Toolkit or any programming language. All aspects of the simulation, including all 4D behaviors, are controlled from a unique, TOPAS Parameter Control System. TOPAS was engineered from the ground up to be flexible, yet easy to use, reliable and repeatable. The code includes a strong focus on “engineering-in” safety, employing a variety of techniques to make it harder for users to make mistakes. Two very brief introduction to TOPAS videos can be found here and here.
TOPAS is further described in the open-access manuscript: Perl J, Shin J, Schumann J, Faddegon B, Paganetti H. TOPAS: an innovative proton Monte Carlo platform for research and clinical applications. Med Phys. 2012 Nov; 39(11):6818-37. (View in: PubMed). This manuscript has has been cited 794 times in Google Scholar.
TOPAS basic concepts were originally created out of an NIH-funded collaboration of the SLAC National Accelerator Laboratory, Massachusetts General Hospital and the University of California at San Francisco. NIH support for TOPAS continues through a U24 grant from the ITCR (itcr.cancer.gov), awarded for the period June, 2018 through May, 2023. TOPAS MC Inc. serves as a central resource for TOPAS users. At last count, our TOPAS User and Development Community included 2372 users at 616 institutions in 67 countries.
While most early applications of TOPAS were in proton therapy, TOPAS is now applied in all areas of radiation therapy research and is also suitable for some medical imaging applications. Work is ongoing to extend TOPAS to radiation biology and to science education. Other potential applications include studies of radiation damage to electronics, particle physics, nuclear physics and astrophysics.
Our mission is to make TOPAS into a tool that fits comfortably into the hands of every medical physicist.
TOPAS MC Inc. is a nonprofit public benefit corporation and is recognized by the IRS as a tax exempt public charity under section 501(c)(3).