Lithotrypsy had advanced somewhat from the days of Webster 1913
. Whereas then it was a major surgical
procedure, involving mechanical destruction of calculi
now the proceure is carried out with ultrasonic waves, generated by a machine known as a lithotripter.
The procedure is typically carried out under anaesthetic, although modern machines do not actually require this. X-rays are used to find the position of stones, which then have ultrasonic waves directed at them. This reduces them to a find sand like material, which can easily pass along the urinary tract, and leave the body without any further assistance.
A more serious procedure is percutaneous lithotrypsy. This involves the insertion of instruments into the abdomen. This is used in cases where the stones are too large for surface lithtrypsy to work, or for kidney stones, as opposed to bladder stones.