MP54-11 ARE WE BANGING OUR HEADS AGAINST THE WALL? THE EFFECT OF TREATMENT HEAD WEAR ON THE OUTCOMES OF EXTRACORPOREAL SHOCKWAVE LITHOTRIPSY

Abstract

You have accessJournal of UrologyStone Disease: Shock Wave Lithotripsy1 Apr 2016MP54-11 ARE WE BANGING OUR HEADS AGAINST THE WALL? THE EFFECT OF TREATMENT HEAD WEAR ON THE OUTCOMES OF EXTRACORPOREAL SHOCKWAVE LITHOTRIPSY Nathan Hoy, Derek Bochinski, Trevor Schuler, Timothy Wollin, and Shubha De Nathan HoyNathan Hoy More articles by this author , Derek BochinskiDerek Bochinski More articles by this author , Trevor SchulerTrevor Schuler More articles by this author , Timothy WollinTimothy Wollin More articles by this author , and Shubha DeShubha De More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.581AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The widely used Storz Modulith F2 lithotripter is rated for head exchange after 1.65 million shocks. With continued usage, the effectiveness of the shocks delivered by the treatment head could theoretically diminish. The objective of this study is to determine whether clinical outcomes are affected by treatment head wear. METHODS We conducted a retrospective chart review of 200 patients undergoing ESWL: 50 consecutive patients immediately preceding, and following 2 separate treatment head exchanges at ~1.65 million shockwaves. Our primary outcome measures were stone free rate (no stone on follow-up imaging), partial stone fragmentation (any decrease in size on follow-up imaging), and fragmentation rate ≤4mm (decrease in stone size with largest residual fragment ≤4 mm), at first follow up (with imaging). Secondary outcomes included complication rates, symptomatic re-presentation within 4 weeks, and re-treatment rates. RESULTS There were no baseline characteristic differences between the pre-exchange and post-exchange groups with respect to mean age (52.7 vs. 52.8 years), mean Charlson Co-Morbidity Index (1.5 vs. 1.3), recurrent stone formers (40% vs. 47%), first time lithotripsy for the stone (85% vs. 77%), mean stone density (912 HU vs. 840 HU), mean skin to stone distance (12.6 cm vs. 12.8 cm), stone location, stone sidedness (46% vs. 44% right side), pre-operative stenting (3% vs. 4%), mean number of shocks delivered (3105 vs. 3089), and mean maximal energy (6.2 vs. 6.1). Mean stone size (9.0 vs. 8.1 mm, p=0.042) was significantly larger in the pre-exchange group. Mean time to follow-up was 2.6 weeks vs. 2.5 weeks, with most follow-up imaging consisting of a KUB (87% vs. 85%), for the pre and post exchange groups, respectively. Stone free (34% vs. 27%), total stone fragmentation (76% vs. 76%), stone fragmentation ≤4mm (48% vs. 42%), re-treatment with ESWL or ureteroscopy (38% vs. 51%), and complication rates (6% vs. 7%), were not statistically different between the pre and post-exchange groups, respectively. CONCLUSIONS Our study is the first to suggest a continuing durability of clinical outcomes, throughout the lifespan of a Storz Modulith F2 lithotripter (over the manufacturer recommended 1.65 million shocks). If the manufacturer recommendation for treatment head longevity is based on clinical outcomes, then there may be room to extend this number without affecting treatment efficacy. However, the ideal number of shocks prior to a decrease in efficacy remains to be determined. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e730 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Nathan Hoy More articles by this author Derek Bochinski More articles by this author Trevor Schuler More articles by this author Timothy Wollin More articles by this author Shubha De More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...