Robot-Assisted Fluoroscopy Versus Ultrasound-Guided Renal Access for Nephrolithotomy: A Phantom Model Benchtop Study

Abstract

Objectives: To evaluate the feasibility of robot-assisted fluoroscopy-guided (RAG) puncture and to compare RAG puncture, utilizing a novel robot system for percutaneous renal access, with ultrasound-guided (USG) puncture. Materials and Methods: We conducted a bench-top study with a renal phantom model using the automated needle targeting with X-ray system. Seventeen urologists participated in this study and performed RAG and USG phantom punctures. The number of needle punctures, device set-up time, and fluoroscopic exposure duration were recorded for the analyses. Results: The single puncture success rates of the RAG and USG punctures were 100% and 70.6%, respectively (p=0.021). The median needle puncture time of RAG puncture was 24% shorter than that of USG puncture (35.0 vs 46.0 seconds; p<0.001), and the median device set-up time of RAG puncture was a minute longer than that of USG puncture (93.0 vs 30.5 seconds; p<0.001). The median duration of fluoroscopic exposure of RAG puncture was longer than that of USG puncture (38.0 vs 6.5 seconds; p<0.001). The surgeon’s self-assessment results demonstrated that the participating urologists found RAG puncture to be safer and have better visibility than USG puncture; they were also more satisfied with RAG puncture. Sub-analysis revealed that, in the RAG group, the attending surgeons had shorter total procedural time than the residents (p=0.045). Conclusion: RAG puncture showed comparable results and accuracy rates with USG puncture for renal access.