Figure 1. Ultrasound-guided percutaneous access nephrolithotomy model developed at the University of Rochester by Dr Ghazi.

Over the past few years, comprehensive surgical training has gone from solely being taught in the operating room (OR) to incorporating advanced training with simulation models outside of the OR. The ability for surgical trainees to be exposed to and perform procedures on a representative model prior to operating on a live patient is invaluable. Urology has been on the forefront of this training, especially in the subspeciality of stones. While multiple models exist (some discussed below), the true challenge is how to arrange exposure of trainees to them. Simulation labs offer a comprehensive yet condensed syllabus to trainees, and we believe they should be a standard part of resident education.

For ureteroscopy exposure, multiple models exist from various industries. Simulation labs are a perfect opportunity for industry to bring in their latest scopes and let trainees practice navigating around simulated kidneys. The exposure to multiple devices (scopes, baskets, wires, lasers, etc) allows trainees (and present faculty) to learn about various features and try out those features before getting them into the OR. In addition to basic exposure to the scopes, simulation training for ureteroscopy has been shown to decrease navigation time when trainees repeatedly practice on the model.¹ That decreased navigation time within simulation models likely translates to navigation time within live patients and leads to shorter operative times, which can help keep down OR costs and may help decrease infectious complications.²

Figure 2. Low-cost ultrasound-guided percutaneous access nephrolithotomy model developed at the University of Arizona.

For percutaneous nephrolithotomy (PCNL) training, there have been several models developed which offer lifelike anatomy to practice percutaneous access (both ultrasound and fluoroscopic) as well as tract dilation. While the Perc Mentor was a pioneer in helping establish a consistent fluoroscopic-guided training model for PCNL,³ more recent models have helped carry on this work utilizing updated technology. For example, Turney developed a silicone biomodel using a 3D printer, which when filled with contrast and sealed can serve as an anatomically correct model for simulating fluoroscopic-guided percutaneous access.⁴ Dr Ghazi and his team at the University of Rochester have developed a validated trainer for all portions of PCNL.⁵ With the increasing popularity of ultrasound-guided access, many advances have been made in incorporating PCNL models aimed at allowing urologists the ability to use ultrasound as an alternative to fluoroscopic percutaneous access. Ultrasound PCNL models allow for trainees to identify target calyces and practice the nuances of making subtle needle adjustments to avoid surrounding structures that are now able to be visualized on ultrasound (Figures 1 and 2). Similar to ureteroscopy simulation training, the benefits of simulated PCNL training have also been proven to translate to the OR, even for experienced surgeons. Using patient-specific anatomy, Ghazi et al developed simulation models, which were then available to a fellowship-trained endourologist to rehearse on prior to planned PCNLs. Compared to cases performed without those rehearsals, the simulation-rehearsed cases showed significant improvements in fluoroscopy time, needle attempts, complications, and additional procedures.⁶

The next frontier of simulation training in stones may reside with virtual reality. A study from UC Irvine demonstrated the feasibility of using CT-based immersive virtual reality (iVR) for preoperative planning.⁷ Surgeons reported a better understanding of the optimal calyx for entry, with the iVR model changing the approach of the operator (ie switch into a different calyx) in 40% of cases. When compared to a matched cohort performed without the assistance of iVR, those who utilized this technology had less blood loss and fluoroscopy time, and potentially better clearance rates.⁷

The validity of simulation training is clear. How to expose trainees to simulation through official simulation labs is not easy and requires time, resources, and a coordinated effort from academic faculty and industry. We recently organized a joint simulation lab with urology trainees from Mayo Clinic Arizona and the University of Arizona. Residents and fellows came together for a day at ASTEC (Arizona Simulation Technology and Education Center), the University of Arizona’s 6,000-square-foot simulation facility designed to represent ORs, intensive care units, and other health care settings (Figure 3, A and B). With industry and faculty support, multiple stations were set up to simulate urological procedures including PCNL, kidney ultrasound, holmium laser enucleation of the prostate, ureteroscopy, urethral bulking agents, transperineal prostate biopsy, female and male urethral slings, and more. The goal was to create a safe environment for junior trainees to learn about various procedures with hands-on experience prior to their exposure in the OR, and for more senior trainees to gain experience refining their skills. Although not always easy, the different models available for simulation training, like those above, can be obtained for these resident labs via a coordinated effort between academic centers. From residents of all levels, we received overwhelmingly positive feedback and have personally noted an extra familiarity with endoscopic procedures in junior residents from their exposure in the simulation lab.

Simulation labs present an educational opportunity that should not be overlooked, especially given the plethora of models now available. Given the positive feedback from our trainees along with the known translation of skills from these labs to the OR, we are encouraged to continue our lab as an annual education opportunity and hope that other training programs pursue similar opportunities.