Initial experience with augmented reality in planning renal access for PCNL

Achieving renal access during percutaneous nephrolithotomy is challenging, with a complication rate of 10-20%. This study aims to assess a novel technique for planning access to the renal collecting system using augmented reality (AR). Using Digital Imaging and Communications in Medicine software (DICOM 2-print), we generated 3-dimensional (3D) models of patients with different types of kidney stones (staghorn, lower pole, and pelvic stones) who underwent PCNL between 2018 and 2022. After viewing the patient's CT scans, surgeons explored the anatomical models using an AR system with a stereoscopic 3D lens array display. Using questionnaires, we quantitatively estimated the model's contribution on a scale of "1" ("poor") to "5" ("excellent") to the surgeon's understanding of stone location, patient anatomy, and ease of access compared to 2D CT imaging. A total of 38 questionnaires were completed by 13 urologists. Estimating renal location, renal pelvis, and stone mass were better demonstrated by AR (5 vs. 4, p < 0.001). The orientation of adjacent organs was better understood using AR (5 vs. 4, p = 0.004). In 86.8% of cases, surgeons preferred using AR models both before and during surgery, with 69.2% suggesting that AR could enhance procedural safety. The time frames for testing the models differed between senior and junior practitioners (p = 0.016) and were significantly reduced with model experience (p < 0.001). When comparing CT to 3D imaging, AR models provide a better understating of stone location, patient anatomy, and route of access to the collecting system. Further research is required to implement this innovative technique preoperatively and intra-operatively.