Automated Needle Targeting with X-ray (ANT-X) - Robot-assisted device for percutaneous nephrolithotomy (PCNL) with its first successful use in human.

INTRODUCTION: To make percutaneous access easier in PCNL, we developed Automated Needle Targeting with X-ray (ANT-X). METHOD: ANT-X uses an image registration software with a closed loop feedback system to autoalign the puncture needle to the desired calyx using the bullseye technique. We tried percutaneous punctures on a live pig model and compared the results with free-hand technique. We then performed our first PCNL in a human subject with the aid of ANT-X. Our patient was a 48 year-old gentleman with a 1.4cm left lower pole stone. RESULTS: Initial results for live animal trial showed radiation exposure for robot-assisted arm during puncture was reduced by 26% compared to the free-hand technique (8.2mGy vs 11.2mGy). In the human trial, obtaining percutaneous access was successful at first attempt. CONCLUSION: ANT-X system can help surgeons feel confident and potentially reduce complications, hence enabling more surgeons to adopt this procedure.

Laparoscopic pyelolithotomy: An emerging tool for complex staghorn nephrolithiasis in high-risk patients.

OBJECTIVES: To evaluate the effectiveness of laparoscopic pyelolithotomy (LP) for staghorn stones (>3-4 cm) in patients with chronic liver disease or coronary artery disease. PATIENTS AND METHODS: In all, 49 patients underwent LP; they were divided into four groups, with stones in group 1 in the renal pelvis only, in group 2 in the renal pelvis and one calyx, in group 3 in the renal pelvis and two calyces, and in group 4, in the renal pelvis and more than two calyces. Patient demography, stone characteristics, surgical outcomes and complications were evaluated. RESULTS: The mean stone-free rate in one session was 90% among all groups. The mean (SD) stone size was 4.27 (1.72) cm. The stone-free rate decreased with greater stone burden, but the operative time, estimated blood loss and need for ancillary procedures increased with stone burden. No blood transfusion was required and one patient each in groups 2 and 4 had a urine leak. CONCLUSION: LP provides acceptable results in complex cases for managing renal stone disease with a larger stone burden in high-risk situations.