A review of the effects of exposure parameters on DAP and ESD on fluoroscopy X-rays systems

During fluoroscopic and interventional procedures, radiographers monitor and record patient DAP/ESD values, from which local DRLs can be established. DRLs are used as a guide for dose optimisation for different imaging modalities. However the relevance of DRLs in paediatric fluoroscopic procedures is questionable. Different factors, e.g. pulse rate, magnification, etc. enable radiographers to optimise the radiation dose received by the patient. This is especially important in paediatric radiology, were optimal exposure is of utmost importance. The fundamental aim of this work is to provide adequate information to radiographers of the effects different parameters have to the DAP and ESD values on the various fluoroscopy systems in the hospital. Two mobile and one fixed fluoroscopy system were studied. Results indicate that at higher pulse rates, the increase in DAP and ESD rates when going from one pulse rate to another vary across the different systems, with one system increasing by up to 160%. Results also showed a decrease in DAP values of up to 30% when changing from full field to higher magnification settings while the ESD rates increased by up to 16%. A comprehensive investigation is presented here of the effects the varying parameters have on DAP and ESD values. Information sheets are being developed for the respective unit to improve the radiographer’s understanding of the systems. This will subsequently provide more confidence in their decisions with real time dose optimisation during complex procedures, which will be in line with image gently protocols and the new BSS.