A rapid method of production of irregular-shaped fields for use with patients receiving electron radiotherapy

A 3D technique for simulation of irregular electron treatment fields using a digital camera

Cerrobend inserts, which define electron field apertures, are manufactured at our institution using perspex templates. Contours are reproduced manually on these templates at the simulator from the field outlines drawn on the skin or mask of a patient. A previously reported technique for simulation of electron treatment fields uses a digital camera to eliminate the need for such templates. However, avoidance of the image distortions introduced by non-flat surfaces on which the electron field outlines were drawn could only be achieved by limiting the application of this technique to surfaces which were flat or near flat. We present a technique that employs a digital camera and allows simulation of electron treatment fields contoured on an anatomical surface of an arbitrary three-dimensional (3D) shape, such as that of the neck, extremities, face, or breast. The procedure is fast, accurate, and easy to perform.

Simulation of irregularly shaped electron treatment fields using a digital camera

The use of a digital camera to simulate irregularly shaped electron treatment fields was investigated. The simulation of electron treatment fields, drawn on patient's skin or shell, is required to fabricate cerrobend inserts for defining the beam apertures. The use of the digital camera made the procedure very easy and time efficient, which was essential for patient comfort as well. The mathematical formulism and accessories required to use the camera for simulating the electron treatment fields are described in detail.