Comparative analysis of radiation dose and low contrast detail detectability using routine paediatric chest...

To compare low contrast detail (LCD) detectability and radiation dose for routine paediatric chest X-ray (CXR) imaging protocols among various hospitals.

CDRAD 2.0 phantom and medical grade polymethyl methacrylate (PMMA) slabs were used to simulate the chest region of four different paediatric age groups. Radiographic acquisitions were undertaken on 17 X-ray machines located in eight hospitals using their existing CXR protocols. LCD detectability represented by image quality figure inverse (IQF_inv) was measured physically using the CDRAD analyser software. Incident air kerma (IAK) measurements were obtained using a solid-state dosimeter.

The range of IQF_inv, between and within the hospitals, was 1.40-4.44 and 1.52-2.18, respectively for neonates; 0.96-4.73 and 2.33-4.73 for a 1-year old; 0.87-1.81 and 0.98-1.46 for a 5-year old and 0.90-2.39 and 1.27-2.39 for a 10-year old. The range of IAK, between and within the hospitals, was 8.56-52.62 μGy and 21.79-52.62 μGy, respectively for neonates; 5.44-82.82 μGy and 36.78-82.82 μGy for a 1-year old; 10.97-59.22 μGy and 11.75-52.94 μGy for a 5-year old and 13.97-100.77 μGy and 35.72-100.77 μGy for a 10-year old.

Results show considerable variation, between and within hospitals, in the LCD detectability and IAK. Further radiation dose optimisation for the four paediatric age groups, especially in hospitals /X-ray rooms with low LCD detectability and high IAK, are required.