Optimization of simulated cranial, thorax, and abdominal examination in paediatric digital radiography

This study was aimed to obtain optimum parameter combination in simulated cranial, thorax, and abdominal examinations using computed radiography (CR) and direct digital radiography (DDR) systems. Optimization was performed using in-house phantom with contrast objects on Siemens Luminos Agile Max DDR and Siemens Axiom Luminos TF CR. Paediatric patients were separated into four age groups; 0-1 year (group A), 1-5 years (group B), 5-10 years (group C), and 10-15 years (group D). Slab phantoms with different total thickness were used to simulate patients belonging to each age group for different anatomical region (cranial, thorax, and abdomen). Optimization were performed in three steps; first kVp, followed by mAs, and then additional filter optimization. All the steps of optimization were performed based on FOM (figure of merit) values calculated as ratio of squared SDNR (signal difference to noise ratio) and entrance surface dose with the highest FOM representing the optimum condition. The results of this optimization were evaluated based on the highest FOM generated from each exposure. For both CR and DDR, optimum parameters (i.e. highest FOM) are different for each age group and anatomical region. Even with different X-Ray units, the CR device had slightly similar optimized parameters.