urinary tract calculi in the bladder. Throughout most of the history of humans, this was the predominant form of urinary tract stone disease, mentioned in the Hippocratic oath, and giving rise to the common ancient surgical procedure, lithotomy. In much of the world, bladder stone disease has become uncommon and renal and ureteral stones (usually of different origins) have become more common. Bladder stones are now typically seen in patients with neurogenic bladders, urinary tract reconstruction, or infravesical obstruction. SYN: bladder calculus.