Wagenius M. et al., 2022: Factors influencing stone-free rate of Extracorporeal Shock Wave Lithotripsy (ESWL); a cohort study.
Wagenius M, Oddason K, Utter M, Popiolek M, Forsvall A, Lundström KJ, Linder A.
Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden.
Department of Urology Helsingborg Hospital, Helsingborg, Sweden.
Department or Urology, Örebro University Hospital, Örebro, Sweden.
Institution of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden.
Objective: To evaluate the success rate of Extracorporeal Shock Wave Lithotripsy (ESWL) therapy and identify relevant treatment-specific factors affecting stone-free rate (SFR) after ESWL.
Materials and methods: All ESWL treatments in the years 2016-2019, in Ängelholm Hospital, Skåne, Sweden were analysed retrospectively. Primary outcome was stone-free rate (SFR) at 3 months. Univariate logistic regression was used followed by multivariable regression. Lasso analysis was made to adjust for treatment-specific factors such as age, stone size, skin-to-stone distance (SSD), stone attenuation, number of treatments, stone location and presence of a urinary stent.
Results: Factors affecting successful ESWL treatment were lower age (p < 0.001), smaller stone size and volume (both p = 0.001). SSD, stone attenuation, sex, laterality and drainage did not have an effect on SFR in this study. After the first ESWL treatment session, 46.7% of the patients were stone-free.
Conclusion: Results indicate that stone size and age are the most predictive factors for ESWL outcome. Based on this, we present a simple model for prediction of SFR after ESWL, to be used when counseling patients before ESWL treatment.
Scand J Urol. 2022 Apr 9:1-7. doi: 10.1080/21681805.2022.2055137. Online ahead of print. PMID: 35400281.
The experience with ESWL of 707 patients is reported. With a MODULITH® SLX-F2 583 renal and 124 ureteral stones were treated using the small focus in 98,6%.
Success or SFR were defined as fragments 4(1+odds). For counselling a patient, a very simple visual diagram predicting SFR/treatment success with age and maximum stone size as objective factors is offered. That is a nice gimmick to tell the future. The drawback might be that no such simple diagram for URS or PNL is available to inform the patient on all treatment aspects.