Plaque Simulator

IMPORTANT NOTICE: If you have already, or intend to update to MacOS 10.13 (High Sierra) or MacOS 10.14 (Mojave), please read this page regarding a cosmetic issue when loading patient files created under prior versions of MacOS. Plaque Simulator version 6.6.2 is compatible with MacOS 10.13. The changes are described in the Whats new page.

IMPORTANT NOTICE: January 2015, to all users of BEBIG Plaque Simulator version 5 and earlier versions (PS5). PS5 is now 21 years old and has reached end-of-life as a sustainable product. The computers for which it was designed (Apple Macs with PowerPC processors) were phased out by Apple in 2005 and the last operating system that supported software emulation of the PowerPC processor was OSX 10.6 which was released in 2009.

Plaque Simulator version 6 (PS6) has been in development and testing since 2012 by Eye Physics, LLC and is now available to replace PS5. PS6 is designed for recent Apple Macintosh computers with Intel Xeon, Core i7 and i9 multicore processors running MacOS versions 10.11 through 10.14 (Mojave). PS6 leverages multiple cores to accelerate dosimetry calculations by distributing the work uniformly and concurrently amongst all available logical cores. Hardware recommendations are discussed in the PS6 User Guide.

Plaque Simulator is a 3D treatment simulation and modeling package for I-125, Pd-103, Ir-192 and Ru-106 plaque therapy of ocular tumors. Applicable ophthalmic tumors include choroidal melanoma in adults, retinoblastoma in young children and various forms of metastatic disease. In plaque therapy, small radioactive sources are embedded in a gold or silver bowl-like shell called a "plaque" which is placed on the surface of the eye adjacent to the tumor. The plaque directs therapeutic radiation towards the tumor while shielding the orbit and other surrounding anatomy.

The video below illustrates some of the features of Plaque Simulator image based conformal treatment planning which fuses CT or MR imaging, ultrasound and fundus photography to build a detailed model of each patient's eye. In this example isodose lines are plotted on the meridian plane passing through the tumor apex, a translucent isodose surface enclosing the tumor mass, and points of interest along the central axis of the plaque. Also seen are the rectus and oblique muscle attachments, the lens, optic nerve, I-125 seeds inside the plaque, the plaque shell, and its suture eyelets with their coordinate projections onto the scleral surface. These suture coordinates are provided to the surgeon to simplify implanting the plaque. This movie was created using PS version 6.

For Plaque Simulator technical support contact Eye Physics directly at

Plaque Simulator 6 is the property of Eye Physics, LLC. Following his retirement from the University of Southern California (USC) in 2010, Emeritus Professor of Radiation Oncology, Dr. Melvin Astrahan, PhD, incorporated Eye Physics and began the process of completely rewriting and modernizing the technologies he pioneered during his tenure at USC from 1984-2010. In North America, email technical support questions, bug reports and requests for teleconferencing appointments to the author Dr. Astrahan in Los Angeles at

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