Bladder stones are fairly common in dogs. They are less common in cats, and also occur in tortoises and iguanas. Bladder stones in dogs are most often composed of struvite or calcium oxalate crystals. The difference between them is that calcium oxalate stones like a more acid urine, struvites prefer a more alkaline urine.
Bladder stones can be treated with a surgical procedure called a cystotomy, which involves opening up the bladder and extracting the stones. Before surgery, a urinalysis and blood panel are performed. The urinalysis helps determine what type of stones might be in the bladder. Sometimes, the crystals will show up on a urinalysis, and there is usually a bacterial infection associated with struvite stones. There are cases of bladder stones where crystals do not show up in the urine.
Cystoscopy involves inserting a special scope in the bladder. Using instruments passed through channels in the sheath of the scope, the stones are pulled out. This works only if the stones are not too big and only with female dogs, as the scope is not flexible. The female's urethra is straight, whereas a male's is curved and will not allow the passing of the scope.
MCT News Service