Computed tomography radiation dose optimization for the diagnosis of acute rib fractures in infants investigated for suspected physical abuse: An experimental animal study.

Alzahrani, NM.; Paddock, M.; Jeanes, A.; Cohen, MC.; Offiah, AC.

Computed tomography radiation dose optimization for the diagnosis of acute rib fractures in infants investigated for suspected physical abuse: An experimental animal study.

All Authors

Alzahrani, NM.

Paddock, M.

Jeanes, A.

Cohen, MC.

Offiah, AC.

LTHT Author

Jeanes, Annmarie

LTHT Department

Leeds Children's Hospital
Radiology

Publication Date

2025

Item Type

Journal Article

Abstract

BACKGROUND: Computed tomography (CT) of the chest has proven promising in improving rib fracture detection in children with suspected physical abuse (SPA). However, concerns regarding relatively higher radiation exposure make it less desirable in routine clinical practice. OBJECTIVE: To investigate the effect of varying CT scanning parameters (tube voltage and current) on radiation dose, image quality and diagnostic performance (i.e., sensitivity and specificity), and to optimize chest CT scanning parameters for the detection of acute rib fractures in infants with SPA. METHODS: Following traumatic induction of rib fractures, five rabbits underwent post-mortem CT scanning at two centres using combinations of tube voltage (80 and 100 kV) with progressive 10 % reduction in tube current (mA) until 10 mA was reached. Two pediatric radiologists, blinded to the scan parameters, independently assessed subjective image quality using a 5-point Likert scale and recorded presence of acute undisplaced rib fractures. Linear regression between the readers' scores for image quality and effective dose (ED) was used to determine the imaging parameters providing the lowest ED with acceptable diagnostic image quality. RESULTS: There was moderate agreement between readers for image noise (Centre 1, kappa (k) = 0.5; Centre 2, k = 0.45) and sharpness (Centre 1, k = 0.59; Centre 2, k = 0.55). The parameters with acceptable diagnostic image quality at Centre 1 were 80 kV/30 mA with an ED of 0.32 mSv and sensitivity and specificity of 93.5 % and 99.4 %, respectively, and at Centre 2 80 kV/40 mA with ED of 0.2 mSv and sensitivity and specificity of 84.3 % and 99.1 %, respectively, approaching the combined ED for initial and follow-up skeletal survey chest radiographs performed for SPA (0.14 mSv). CONCLUSION: Low-dose CT (with ED approaching that of chest radiographs performed for SPA) may provide images of sufficient diagnostic quality to confidently diagnose rib fractures. Studies in children with SPA are required.