Robotic Precision vs. Human Dexterity—Benchtop Comparative Study of Free-Hand vs. Robotic-Assisted Puncture in Fluoroscopy-Guided Percutaneous Nephrolithotomy

Abstract

Introduction: Percutaneous nephrolithotomy (PCNL) is the standard procedure for treating large kidney stones, especially those measuring over 20 mm or staghorn stones. Accurate placement of the tract into the renal collecting system of interest is crucial. Objective: To compare the free-hand puncture technique with robotic-assisted puncture during fluoroscopy-guided PCNL on a phantom kidney model in terms of efficiency and safety. A self-assessment of confidence levels after each puncture was recorded. Study Design: This prospective single-center benchtop study was conducted at the University Malaya Medical Centre (UMMC). Four urological residents participated and performed phantom punctures using both the free-hand bull’s eye technique and the automated needle targeting system with X-ray (ANT-X). Each resident performed a total of 60 punctures on the renal phantom models, with 30 punctures using the free-hand technique and 30 punctures using the ANT-X robotic-assisted system. Results: A total of 240 needle insertions were conducted, with 120 in the ANT-X group and 120 in the free-hand group. The success rate of needle insertions was 100% in both groups. However, the study revealed that the ANT-X group required, on average, an additional 51 s for needle puncture compared to the free-hand group (p < 0.001). In terms of fluoroscopic exposure, the ANT-X group exhibited significantly lower radiation exposure compared to the free-hand group (p < 0.001). Sub-analysis showed that puncture time remained consistent regardless of the technique used, but fluoroscopic screening time decreased with increasing participant experience. The ANT-X group also resulted in significantly lower radiation exposure during initial sessions compared to the free-hand technique. Surgeons’ self-assessment of confidence levels indicated a high level of confidence in needle puncture. Conclusions: Our benchtop study comparing the efficacy and safety between free-hand and ANT-X phantom punctures revealed comparable results. The needle puncture technique facilitated by the ANT-X system showed promising results in terms of reducing fluoroscopic exposure, albeit at the cost of longer operative times. This technology holds promise for novice surgeons who are in the early stages of their learning curve and might be useful for experienced surgeons looking to reduce radiation exposure.