Comparative evaluation of soft-tissue foreign body detection using ultrasound and radiography: A phantom study

Abstract

Soft-tissue foreign bodies (STFBs) are common clinical presentations requiring accurate imaging for diagnosis and management. This experimental phantom study compared ultrasound and general radiography in detecting STFBs of varying materials and depths using anatomically relevant cow foreleg models. Eight foreign bodies; metallic, organic, and inorganic were inserted at depths of 1 cm, 3 cm, and 5 cm. Both modalities were performed, and image visibility was scored by two radiologists using standardized criteria, achieving substantial inter-rater agreement (κ = 0.74). Ultrasound demonstrated significantly higher visibility scores than radiography (p = .01), confirming superior diagnostic performance. Although ultrasound image quality declined slightly with depth, differences were not statistically significant (p = .75). Radiographic detection remained consistent across depths (p = .14) but was strongly influenced by material radiopacity, limiting its utility for radiolucent objects. These findings align with existing literature supporting ultrasound as a reliable modality for STFB detection, particularly when foreign body composition is unknown. Despite limitations, including small sample size and lack of clinical variability, this study provides clinically relevant evidence reinforcing ultrasound as a potential first-line imaging technique for suspected STFBs.