EAU 2018: New Techniques in Renal Puncture During Percutaneous Nephrolithotomy Did They Make It Safer And Easier? 

Copenhagen, Denmark (UroToday.com) Dr. Skolarikos, professor of clinical urology from the National and Kapodistrian University in Athens, Greece, presented his findings on novel perioperative technologies being developed for percutaneous nephrolithotomy (PCNL). In his lecture, Dr. Skolarikos discussed novel imaging techniques, imaging procedures, robotic systems, navigation systems, finite elements models, and computer graphics and imaging processing.   

In regard to imaging techniques for puncture of the kidney during PCNL, there is a very limited number of techniques, mostly involving two dimensional imaging techniques such as C-arm fluoroscopy and US (US). As a novel approach, Dr. Skolarikos explained that there is development of three dimensional US that will be able to be used in the operating room to give the surgeon real time imaging of the kidney during needle puncture. Additionally, it was recommended that fusion technology of preoperative computed tomography (CT) or magnetic resonance imaging (MRI) scans be combined with real time US in the operating room to give a 3D image of the kidney during needle puncture. This technology is commonly used in prostate biopsy and could be quite efficacious in PCNL. Furthermore, Dr. Skolarikos introduced a novel “all seeing needle” equipped with a camera at the tip allowing the surgeon a real time image of the kidney as the puncture occurs. 

Additional surgical tools explored in this lecture included medical robots for PCNL with image guided modalities for percutaneous access. One such robotic arm, named the PAKY-RCM, is controlled by a joystick while the robotic needle driver advances the needle under direct fluoroscopic supervision by a C-arm which produces and 87% success rate in renal puncture for PCNL. Additionally, Dr. Skolarikos presented CT and MRI guided robots for PCNL. An additional surgical modality discussed was computer-aided surgery for PCNL which uses medical imaging and tracking systems for augmented reality. This is carried out by emphasizing the target structures of surgery and surrounding tissues in preoperative data then using image segmentation algorithms for the production of this augmented reality to allow the surgeon a more accurate visualization of the renal anatomy during surgery.

An interesting visualization technique that was shared during this lecture was the use of an iPad for the visualization of the kidney using augmented reality. First, preoperative imaging was carried out and the images were segmented on a computer which is then sent to the iPad for preoperative planning. Furthermore, this technology can be used by attaching markers to the patient and using the iPad to detect these markers with the camera for intraoperative visualization of the renal anatomy using augmented reality.   

Dr. Skolarikos concluded his speech by presenting a new technique on percutaneous access that he was quite impressed by. This procedure utilized electromagnetic tracking by attaching small magnets to a ureteroscope and the tip of the puncture needle. The ureteroscope would be inserted into the kidney to the calyx of choice, then the needle would be inserted into the kidney in an attempt to connect the two magnets with the help of tracking software to aid the insertion. This technology has been used in porcine studies but has not yet made it to the clinical field of surgery. Additionally, the technique and devices necessary to operate is relatively inexpensive, making it an extremely viable tool to one day be used in the clinical setting. 

Presented by:  A. Skolarikos, Urology Athens Medical School, National and Kapodistrian University Sismanogleio General Hospital, Athens, Greece 

Written by: Zachary Valley MD, (Department of Urology, University of California-Irvine) at the 2018 European Association of Urology Meeting EAU18, 16-20 March, 2018 Copenhagen, Denmark