Failure of holmium:yttrium-aluminum-garnet laser lithotripsy in two horses with calculi in the urinary bladder.

The study investigates the unsuccessful use of holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripsy in breaking up urinary bladder stones in two horses, with alternate methods then used for successful stone removal.

Methodology and Purpose

• The study was conducted in order to test the efficacy of holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripsy in treating urinary bacterial stones in horses, a treatment that has been successful in human medicine.
• Two horses, a mare and a gelding, were reported to have calculi in their urinary bladders and this procedure was attempted on them.

Findings

• Unfortunately, the Ho:YAG laser lithotripsy was not successful in adequately fragmenting the urinary stones in both horses. The stones remained intact and the procedure proved to be inefficient.

Subsequent Treatments

• For the gelding, a different type of laser lithotripsy – pulsed dye laser lithotripsy – was then used, which was successful in breaking down the urinary stone.
• In the mare, the urolith had to be manually removed via the urethra. This was a more invasive procedure, but was necessitated by the failure of the laser lithotripsy technique.

Conclusion and Implications

• This study indicates that while Ho:YAG laser lithotripsy may work effectively on humans, this is not necessarily the case for treating horses. The differences in physiology and the nature or composition of the urinary stones might be contributing factors to this failure.
• The researchers recommend that other methods of removing bladder stones should be considered for equine patients, with manual removal or the use of pulsed dye laser lithotripsy being potential options.