Paris, France (UroToday.com) In his presentation, Dr. Alexey Martov introduced a novel modification to the ever-popular miniaturization to the percutaneous nephrolithotomy (PCNL) procedure. This modification uses a technology known as the ultra-mini-percutaneous nephrolithotripsy (UM-PCNL), which has been previously shown to be a safe and efficient procedure for renal stones less than 2 cm with a holmium laser. However, Dr. Martov offered a twist to the original technique by using a new Thulium SuperPulse Fiber Laser (TSPFL) rather than the traditional holmium laser.
Recently, both miniaturization of PCNL and thulium lasers have become extremely popular in the field of endourology and Dr. Martov and his team at the Federal Medical-Biological Agency of Russian Federation State Institute of Continuous Medical Education in Moscow attempted to combine these technologies and evaluate the patients’ stone free rate and the safety of the procedure itself.
For this procedure, a 200 micron thulium SuperPulse laser fiber was inserted into a 7.5 nephroscope complete with two channels to complete the combinative technology previously described. Routine preoperative multispiral CT (MCT) exams were underwent by each patient to determine stone size, location, and stone density. Stone density varied from 670 to 1430 hounsfield units (HU). The laser mode for fragmentation was 1-1.5 J and 15-30 Hz while settings of 0.1-0.3 J and 50-100 Hz were used for dusting. Stones were extracted through the nephrostomy sheath via the Venturi effect. High supracostal access was used in 11 cases. Control MCT exams to determine stone free status 30 days postoperatively was additionally underwent by each patient.
Following the completion of testing, 34 patients and 39 stones were operated on with the UM-PCNL and TSPFL technology. Upon analysis of MCT scans 30 days postoperatively, there was a 94% stone-free rate (no residual stones). The remaining 6% of patients had residual, clinically insignificant stones less than 3 mm. The average operative time using this technique was 29±9 minutes with a lasering time of 8±6. No bleeding or perforation was observed, however, the postoperative stay was 3.4±1.2 days following surgery.
At the conclusion of his presentation, Dr. Martov reiterated his appreciation for the popularity of the mini-PCNL techniques and thulium laser. Due to the success from his study, he thoroughly endorsed the combination of UM-PCNL and TSPFL technologies to treat stones less than 2 cm.
Figure 1: An example of renal stones following breakage via ultra-mini-percutaneous nephrolithotripsy (UM-PCNL) and Thulium SuperPulse Fiber Laser (TSPFL). There is almost no “snow storm” effect after the use of this technique.
Presented by: Alexey Martov, MD, Ph.D. Head of Urology Department, Federal Medical-Biological Agency of Russian Federation State Institute of Continuous Medical Education, Division of Urology, Moscow, Russia
Co-Authors: Dmitry Ergakov, MD, Ph.D., Associate Professor1 Andrey Andronov, Mirab Guseyno1, Vincent De Coninck, MD, FEBU, Urologist2, Etienne Keller, MD, FEBU, Fellow of the ES3, Professor Olivier Traxer3
Author Affiliation:
1. Federal Medical-Biological Agency of Russian Federation State Institute of Continuous Medical Education, Division of Urology, Pletnews Municipal Hospital, Moscow, Russia,
2. AZ Klina
3. Sorbonne Université, Clinical Research Group n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, AP-HP, Hôpital Tenon, Paris, France
Written by: Zachary Valley, Twitter: @ZacharyAValley, Department of Urology, University of California-Irvine, medical writer for UroToday.com at the 36th World Congress of Endourology (WCE) and SWL - September 20-23, 2018 Paris, France