Simulation for ultrasound-guided renal biopsy using boiled egg

Real-time ultrasound-guided renal biopsy is generally applied to diagnose multiple kidney diseases. A practical simulation model is desired since it is an invasive technique with higher risks of complications such as bleeding. We developed a simple simulation tool for ultrasound-guided renal biopsy using boiled eggs. Boiled chicken eggs were embedded in the agar, and a biopsy simulation was performed using a real-time ultrasound-guided technique as the renal biopsy simulator by trainees and biopsyproficient nephrologists, and the feedback from the participants was obtained. The ultrasonographic evaluation revealed a clear contrast between egg yolk and white, which clearly mimicked the kidney cortex and medulla region. In addition, we observed the needle entering the egg white under needle penetration, and we obtained the biopsy core consisting of egg white. As for the simulations, all the participants succeeded in obtaining the appropriate samples. A total of 92% of the trainees agreed that the simulation could reduce their fears of performing renal biopsies in patients. In addition, all the trainees and biopsy-proficient nephrologists recommend using the simulator for trainees before conducting renal biopsies on patients. The total cost of the simulator was low (< USD 1/simulator). Collectively, our simulation tool using boiled eggs may be a good candidate for practical simulation models of renal biopsy.