A paediatric X‐ray exposure chart

Abstract

The aim of this review was to develop a radiographic optimisation strategy to make use of digital radiography (DR) and needle phosphor computerised radiography (CR) detectors, in order to lower radiation dose and improve image quality for paediatrics. This review was based on evidence-based practice, of which a component was a review of the relevant literature. The resulting exposure chart was developed with two distinct groups of exposure optimisation strategies – body exposures (for head, trunk, humerus, femur) and distal extremity exposures (elbow to finger, knee to toe). Exposure variables manipulated included kilovoltage peak (kVp), target detector exposure and milli-ampere-seconds (mAs), automatic exposure control (AEC), additional beam filtration, and use of antiscatter grid. Mean dose area product (DAP) reductions of up to 83% for anterior–posterior (AP)/posterior–anterior (PA) abdomen projections were recorded postoptimisation due to manipulation of multiple-exposure variables. For body exposures, the target EI and detector exposure, and thus the required mAs were typically 20% less postoptimisation. Image quality for some distal extremity exposures was improved by lowering kVp and increasing mAs around constant entrance skin dose. It is recommended that purchasing digital X-ray equipment with high detective quantum efficiency detectors, and then optimising the exposure chart for use with these detectors is of high importance for sites performing paediatric imaging. Multiple-exposure variables may need to be manipulated to achieve optimal outcomes.

Imaging neonates within an incubator – A survey to determine existing working practice

“…Many studies still advocate the use of a low kV and relatively high mAs values as standard practice, 3,9,21 although Rizzi et al 9 did conclude after an optimisation study that higher kV and lower mAs can reduce the radiation dose and still provide the same image quality (60 kV/1 mAs). Another attempt was made 22 to systematically search the literature for paediatric radiography exposure techniques and subsequently develop an updated paediatric exposure chart. This study concluded that the optimal exposure factors for a neonate (0e6 months) were 63 kVp and 1.6 mAs which is still much higher than the average exposure factors found within the current study.…”

“…This was reinforced by some exposure charts having only one recommended kV and mAs for neonates aged 0e6 months. 22 Seven (37%) of the responding departments used a set SID for acquiring CXRs on neonates within the incubator, however only three specified this distance (100 cm). Over half of the remaining responding departments used the maximum achievable SID for imaging the neonatal chest within incubators.…”

“…Although consideration was given to the variation in exposure factor selection and the different acquisition technologies (CR v DR) used, this could have been explored further in terms of the specification of mobile X-ray units as this may influence exposure factor selection. In addition, neonatal body weight was not considered as part of the same question, although a few studies on exposure charts and neonatal exposures 21,22 along with guidelines form the European Commission 29 do not separate exposure parameters between neonates of different body sizes. It must be noted that only a single response was extracted from each department and was used as the best judge of existing working practices.…”

Effects of Plastic Wedges on Whole Foot Radiograph in Anteroposterior and Oblique Positions

“…The X-ray tube current was set at 100 milliamperes (mA) and the time of exposure was 0.02 sec (s)(2 mAs) (Knight, 2014). Plastic wedges were mounted on the collimator of X-ray machines.…”

Construction and validation of a low cost paediatric pelvis phantom

“…PMMA was used as the soft tissue equivalent [24,25] (Figure 1). PoP has been reported [25] as a possible cortical bone substitute and has been used in literature for imaging of paediatric distal extremities [26] and the construction of body contours [27]. The problem with this substitute is that its density does not exactly match that of paediatric cortical bone [28].…”