Does Stone Entrapment With "Uro-Net" Improve Ho:YAG Laser Lithotripsy Efficiency in Percutaneous Nephrolithotomy and Cystolithopaxy?: an In Vitro Study

• Autor(a) principal: Marchini,Giovanni Scala
• Data de Publicação: 2013
• Outros Autores: Rai,Aayushi, De,Shubha, Sarkissian,Carl, Monga,Manoj
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: International Braz J Urol (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1677-55382013000400579
• topic: Lithotripsy; Laser; Nephrostomy; Percutaneous; Calculi

Purpose to test the effect of stone entrapment on laser lithotripsy efficiency. Materials and Methods Spherical stone phantoms were created using the BegoStone® plaster. Lithotripsy of one stone (1.0g) per test jar was performed with Ho:YAG laser (365µm fiber; 1 minute/trial). Four laser settings were tested: I-0.8J,8Hz; II-0.2J,50Hz; III-0.5J,50Hz; IV-1.5J,40Hz. Uro-Net (US Endoscopy) deployment was used in 3/9 trials. Post-treatment, stone fragments were strained though a 1mm sieve; after a 7-day drying period fragments and unfragmented stone were weighed. Uro-Net nylon mesh and wire frame resistance were tested (laser fired for 30s). All nets used were evaluated for functionality and strength (compared to 10 new nets). Student's T test was used to compare the studied parameters; significance was set at p < 0.05. Results Laser settings I and II caused less damage to the net overall; the mesh and wire frame had worst injuries with setting IV; setting III had an intermediate outcome; 42% of nets were rendered unusable and excluded from strength analysis. There was no difference in mean strength between used functional nets and non-used devices (8.05 vs. 7.45 lbs, respectively; p = 0.14). Setting IV was the most efficient for lithotripsy (1.9 ± 0.6 mg/s; p < 0.001) with or without net stabilization; setting III was superior to I and II only if a net was not used. conclusions Laser lithotripsy is not optimized by stone entrapment with a net retrieval device which may be damaged by high energy laser settings.