A multiple layer structure comprising a first and a second skin layer, each skin layer composed of a polypropylene containing polymer, and a radio frequency susceptible layer adhered to and between the first and second skin layers. The systems have an interface which is adapted to receive information related to a prescribed radiation dose, a predefined target volume within a patient, and parameters associated with an external beam delivery unit. Each average white value is compared to a predetermined reference value to determine a correction value for each pixel. These probe units are configured through a central master unit and each of the probe units may have different configurations according to the demand of network administrators.