AUA 2019: Comparison of Dusting and Fragmenting Using the New Super Pulse Thulium Fiber Laser to a 120W Holmium:YAG Laser

Chicago, IL ( Currently, the gold standard for laser lithotripsy is using the Holmium:YAG laser during standard stone surgery. This type of laser has progressively been advanced throughout the years, but limitations for pulse frequency, fiber size, and power are still persistent. A new competitor is believed to offer superior settings to the standard laser. Dr. Ben Chew, from the University of British Columbia, sought to evaluate the performance of the new Super Pulse Thulium Fiber laser compared to the standard.

Begostones remains as an alternative to stones given their similar physical features to calcium oxalate monohydrate stones. Dr. Chew and his research team used standard Begostones for this study, and these phantom stones were reduced using a fragmenting or a dusting method. Fragmenting was performed using 120W Holmium:YAG laser, while dusting was performed using a Thulium laser fiber. These procedures were performed until the particles were reduced to less than 1 mm.

They found that the total time of fragmenting was much faster while using the Thulium fiber laser at its ideal laser setting. Further, they concluded that this was even more prominent when dusting these stones. Of note, the authors reported that different settings were used for each laser due to the features of each fiber and was set up to mimic their own respective ideal setting. Further, the total mass of the stone material at the end of the procedure was much closer to the original weight when using the dusting method with the Thulium laser fiber.

The clinical importance of this experiment confirms the efficacy of this new, but highly anticipated, Thulium laser fiber as it significantly cuts down the length of lithotripsy and requires less power than the standard holmium laser. In addition, as the author stated in a previous study, when using a 200 micron Thulium fiber laser, there is significantly less retropulsion and laser burn back. Given these results, the presenter believes there are no limitations as it is quieter, easier, and requires less energy than our current gold standard. Though some members of the audience were weary of his comment, there remains a great hope to discover and further implement a more efficacious method in terms of fragmenting and dusting. The next step is to officially perform laser lithotripsy with the Thulium fiber laser in a clinical setting.

Presented by: Ben Chew, MD, Associate Professor of Urology, the University of British Columbia

Co-authors: Bodo E. Knudsen, Columbus, OH, Wilson R. Molina, Lawrence, Kansas
Author Affiliation: the University of British Columbia, The Ohio State University, The University of Kansas

Written by: Sherry Lu, (Department of Urology, University of California-Irvine) at the American Urological Association's 2019 Annual Meeting (AUA 2019), May 3 – 6, 2019 in Chicago, Illinois