Optimising and standardising neonatal chest and abdomen imaging protocols

Abstract

Radiographers perform neonatal radiographic X-ray examinations daily for several diagnostic purposes. The South African radiographer's scope of practice is to provide radiographic X-ray images of optimal quality, while limiting repeats and keeping radiation dose to a minimum. The study aimed to determine which image acquisition techniques and radiation protection measures would contribute to a standardised neonatal chest and abdominal imaging protocol aligned with dose optimisation principles. This aim was addressed by a five-phase research study. In the first phase, a literature-based imaging protocol was determined by means of a literature search. Six articles and four textbooks were used to design the literature-based imaging protocol. This literature-based imaging protocol included imaging aspects such as patient position, main beam direction and recommended exposure factors. The study's second phase was based on neonatal intensive care unit radiographic X-ray examination observations. The observation checklist recorded the technique used by the radiographers and nursing staff during routine radiographic X-ray examinations. The observation checklist was derived from published literature. The researcher observed 158 radiographic X-ray examinations consisting of 109 chest, 16 abdominal, and 33 combined chest and abdominal X-rays. The data from this second phase were used during the third experimental phase of the study. The third experimental phase of the study was to test the protocols observed in phase 2 with consideration of dose optimisation. From the experimental phase, an optimal chest X-ray imaging protocol was designed based on optimal recorded exposure index and deviation index, as well as calculated entrance skin dose (ESD) values. No optimal abdominal imaging protocol was created because there was no optimal recorded exposure index, deviation index, or calculated ESD values for any of the protocols assessed. For the combined chest and abdominal imaging protocol, only an optimal ESD protocol could be created. The experimental phase allowed the design of a one-pager imaging protocol stating the preferred positioning techniques, technical factors, and exposure factors for chest X-rays, abdominal X-rays, and combined chest and abdominal X-rays. The one-pager imaging protocol was used during the fourth implementation phase of the study. The fourth phase included a short training session created for and presented to the participating radiographers. The radiographers completed implementation checklists during the fourth phase when they performed routine radiographic X-ray examinations in the neonatal intensive care unit. Three chest X-rays, two abdominal and 45 combined chest and abdominal X-rays were performed during the fourth phase. The fifth and final stage of the study compared the data accumulated in the second and fourth phases. This comparison was done to determine the effect on exposure index for dose optimisation after the one-pager imaging protocol had been implemented. The comparison indicated that the radiographers did not entirely abide by the imaging protocol. For chest X-rays, the maximum exposure index was reduced from 642 to 163, which was within the recommended range between 50 and 200 for the machine used in the study. For abdominal X-rays, the maximum exposure index was reduced from 583 to 382, within the range of 125–500. The exposure index for the combined chest and abdominal X-rays increased from 724 to 849, which exceeded the recommended range of 125–500. This phase showed that the standardised imaging protocol made a significant difference in neonatal imaging with alignment to dose optimisation techniques. The study's overall goal was achieved to standardise a protocol for the department for radiographic X-ray imaging of the neonatal chest and abdomen, in an attempt to optimise the radiation dose and to guide uniform radiographic evaluation of images of diagnostic value.