Holmium : YAG Laser Lithotripsy for Urolithiasis in Dogs

Background: Laser lithotripsy has been used as an alternative to surgical removal of uroliths in a number of species. Objectives: To determine the effectiveness of laser lithotripsy for removing urocystoliths, urethroliths, or both in dogs, and to determine the influence of dog (chronological order of lithotripsy, endoscope type, sex, body weight) and urolith (total urolith and urocystolith number, presence or absence of urethroliths, largest urolith dimension, and urolith composition) factors on outcome. Animals: Twenty‐five client‐owned dogs with urocystoliths, urethroliths, or both were included. Male dogs were required to weigh ≥6.8 kg. Methods: A single‐arm prospective clinical trial. Laser lithotripsy was performed under general anesthesia. Main outcomes included procedure success and lithotripsy time. Predictors of procedure success and lithotripsy time were selected using logistic and linear regression modeling, respectively. Results: The procedure was successful in 21 of 25 dogs. The procedure was successful more often and in less time in female spayed than in male neutered dogs. Sex was identified as a predictor of success. Univariable analysis showed that sex, endoscope type, and chronological order in which the dog received lithotripsy were significantly associated with lithotripsy time. Stepwise linear regression modeling identified sex, body weight, >10 uroliths, and largest urolith dimension as predictors of lithotripsy time. Conclusions and Clinical Importance: Laser lithotripsy is an effective procedure for the removal of urocystoliths, urethroliths, or both with rare important adverse effects and some limitations in male dogs.