Dose comparative study between two different 3D mobile intra-operative systems

Abstract

3D imaging devices, when coupled to an image guided surgery system, allow for a more precise surgical approach than classical C-arms. Nevertheless, the exposure to radiation of both patient and staff remains a concern and therefore the choice of imaging device plays an important role. Two 3D imaging systems, an imaging mobile device with an O-ring geometry and an imaging mobile device with a C-arm geometry, have been compared in terms of absorbed doses to organs as well as ambient dose equivalent. Absorbed organ doses were evaluated for thoracic and pelvic examinations using TLDs placed within a CIRS anthropomorphic phantom representing an adult woman. Equivalent ambient dose measurements were performed at various positions in the room around the X-ray system using a calibrated dose rate meter. Results suggest that the O-ring system exposes both patient and staff to higher levels of radiation than the C-arm system. Indeed, organ absorbed doses were found to be 3.5 and 1.7 higher for the O-ring system than for the C-arm system for the same thoracic and pelvic explorations respectively. Concerning the ambient dose equivalent, it was found that for a single 3D image acquisition at a radial distance of one meter from the isocentre, measurements for the O-ring system were approximately 30% larger than the C-arm system.