TU-E-TOUR-T-00: Exhibit Hall Guided Tours-Microdosimeters for Therapy (Tuesday).

Tour Leader: Indra Das, NYU Langone Medical Center, New York, NY Tour Guides: Hsui Ai, Indiana University School of Medicine, Indianapolis, IN Aaron Andersen, Indiana University School of Medicine, Indianapolis, IN Olga Volotoskova, NYU Langone Medical Center, New York, NY Participating Vendors: IBA PTW - New York RTI Electronics, Inc. Standard Imaging, Inc. Sun Nuclear Corporation Small fields are increasing used in specialized radiation treatments such as Gammaknife, Cyberknife, Tomotherapy, IMRT, VMAT, SRS and SBRT. Due to small field size electron transport creates lateral electronic disequilibrium and thus dosimetry could be very difficult. Microdetectors are used for small field dosimetry which will be discussed in preface of this tour as below: • Understanding small field e.g. meaning and definition of small field • IAEA definition and approach • Characteristics of microdetectors in terms of perturbation, recombination, correction • Suitability of microdetectors in small field dosimetry.