Lithotripsy

Ectopic ureter laser ablation:
Ectopic ureters are a congenital abnormality (present at birth). This is caused because the ureter (tube connecting the kidneys and bladder) tunnels through the bladder (instead of opening into the bladder, which is the reservoir of urine), but opens into the urethra. This leads to leakage of urine and subsequently, incontinence. Holmium laser can be used to correct ectopic ureters by ablating the ectopic ureter (correcting its opening). Ectopic ureter is one of the most common causes of incontinence in young dogs. This technique is minimally invasive as it does not require surgical intervention (need for incisions or sutures) because it is done via cystoscopy (camera used to visualize the urinary tract). A retrograde ureterogram and cystogram are performed during the ectopic laser ablation to ensure that the ureter is tunneling through the bladder and subsequently opening into the urethra (tube that connects the bladder to the outside) versus connecting and opening directly into the urethra.

Approximately 75% of dogs are continent after undergoing ectopic ureter laser ablation as well as medical therapy. The remainder 25% of dogs that are not continent may require additional therapy such as the placement of a hydraulic urethral occlude or collagen implant.

Besides improving incontinence, correction of an ectopic ureter helps prevent ascending infections to the kidneys because it corrects the direct connection between the urethra and the kidney. Therefore, bacteria would have to colonize the urethra, bladder, and subsequently the kidneys providing maximal protection.

Lithotripsy (use of Holmium laser to break stones/calculi within the bladder and urethra):
Lithotripsy is considered the standard of care for removing stones or calculi from the urinary tract in humans. This technique provides a minimally invasive form of treating bladder or urethral stones in dogs and cats. Laser is used to break stones into small fragments that can be subsequently removed with a basket via cystoscopy. This technique is considered ideal for small bladder or urethral stones in female dogs and cats as well as male dogs [over 10 kg (22 lb)]. Occasionally, dogs less than 10 kg can undergo lithotripsy. However, this depends on the urethral diameter because it is necessary to pass a flexible cystoscope in order to perform this procedure. Lithotripsy can also be used for large bladder stones. Nevertheless, the larger the stone, the longer the procedure may take. Additionally, it is possible that more than one procedure may be necessary to remove large stones or a large number of stones. This occurs when the bladder is very inflamed and bleeds easily/. Excessive bleeding hinders adequate visualization, which is essential for the successful removal of all stones. Besides being less invasive than surgery, lithotripsy does not require suturing the bladder wall, which could serve as a nidus for more stone formation or suture reaction. This technique can be used for all types of stones (e.g. calcium oxalate, struvite, urate, cysteine, among others).