Presentation Authors: Ben H. Chew*, Vancouver, Canada, Bodo E. Knudsen, Columbus, OH, Wilson R. Molina, Lawrence, KS
Introduction: Holmium:YAG laser is the current lithotrite of choice. Although improvements such as higher pulse frequency, longer pulse duration, and multi-pulse technology have advanced the platform, inherent limitations remain include high amperage power requirements, upper limits of pulse frequency, and limitations regarding fiber size. A new technology utilizing Thulium Fiber, which is completely different from Thulium:YAG, offers low pulse energy settings and pulse frequencies over 600Hz. We compared the novel Super Pulse Thulium Fiber laser (SPTF) to a commercially available 120W Ho:YAG laser.
Methods: Standard, homogeneous 5mm3 Begostones were used for all testing (n=10). To test ablation, stones were reduced using a commercially available 120W laser vs the SPTF laser until remaining particles were < 1 mm. To test fragmentation and dusting, resulting particle sizes were measured after delivering a total of 0.5 kJ and 2kJ, respectively.
Results: Ablation to particles < 1 mm was significantly faster using the SPTFL laser 2.23Â±0.22 mg/s (0.6J 30Hz SP) compared to the 120W laser 1.78Â± 0.44 mg/s (0.8J 10Hz SP), p=0.01 (Fig 1). After delivering 0.5kJ, fewer particles >2mm remained for SPTF than for the 120W laser (2.1 vs 7.2 fragments). Clinically, this would equate to fewer basketing passes for SPTF. The dusting rate (1.05Â± 0.08 mg/s ) was significantly faster using SPTF (0.1J 200Hz SP) compared to 120W 0.46Â±0.09 mg/s (0.3J 70Hz Moses), p < 0.001 (Fig 1). After delivering 2kJ, the SPTFL (0.1J 200Hz) produced 40% dust < 0.5mm compared to 24% produced by the 120W laser at 0.3J 70Hz Moses and 14% at 0.3J 70Hz LP, p < 0.005 (Fig 2).
Conclusions: The new Super Pulse Thulium Fiber laser is more efficacious in bench testing than a commercially available 120W laser in fragmenting and dusting stones. In tests of particle sizes, it produced smaller particles of dust. Fragmentation produced fewer fragments using SPTF (and more dust), thus making basketing more efficient.
Source of Funding: The Authoring Physicians are paid consultants to Olympus Corporation of the Americas.