Radiotherapy equipment – Coordinates, movements and scales
Amendment 2 of the International Standard IEC 61217 “Radiotherapy equipment – Coordinates, movements and scales” has been incorporated into this standard. This Amendment 2 increases the possibilities of rotating the patient positioning device around the Z-axis in the fixed IEC coordinate system by two additional rotations: inclination around the longitudinal axis of the patient and tilt around the transverse axis of the patient. The use of two additional degrees of freedom (inclination and tilt) generalizes the coordinate system; as a result it systematically includes three rotations and three translations and thus supports six degrees of freedom in a systematic way. On modern patient positioning devices with six degrees of freedom translation and rotation can be combined such that the same results are obtained as with the eccentric rotation of the upper part of the table. When the data regarding the table position are changed by using the new IEC system, the definition of isocentric rotations is sufficient for transferring any treatment-related information. The eccentric coordinate system of the upper part of the table is however maintained for the purpose of downward compatibility. The International Standard has been prepared by IEC/SC 62C “Equipment for radiotherapy, nuclear medicine and radiation dosimetry”, with the German collaboration of NA 080-00-15 GA NAR/DKE Gemeinschaftsausschuss “Strahlentherapie” (NAR/DKE Joint Committee “Radiotherapy”) of the Radiology Standards Committee (NAR) at DIN, the German Institute for Standardization, collaborating with Deutsche Röntgengesellschaft (German Radiological Society) and the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE and Deutsche Gesellschaft für Nuklearmedizin e. V. (DGN) (German Society of Nuclear Medicine), Deutsche Gesellschaft für Medizinische Physik e. V. (DGMP) (German Society for Medical Physics) and Deutsche Gesellschaft für Radioonkologie e. V. (DEGRO) (German Society for Radio Oncology).