When evaluating foreign bodies in soft tissue, an imaging interface- such as a standoff pad- can improve imaging of superficial structures.
Common image interfaces include gel, commercial standoff pads, saline bags, and water baths.
Water baths are primarily used for imaging the hands and feet, but a recent study explored a water-filled patient belongings bag as a novel alternative. This method gives the benefit of the same elevated standoff that water baths provide, while accommodating larger extremities that may not fit in traditional setups.
The study found no significant difference between the patient belonging bag and a water bath for identifying a FB in a porcine model. Saline bags had the lowest image quality.
References
Vega C, Lindsay R, Shokraneh K, et al.. POCUS Standoff: Comparing Ultrasound Interfaces for Soft Tissue Foreign Body Imaging. Pediatric Emergency Care. 2025; 41 (5): 354-358. doi: 10.1097/PEC.0000000000003359.
