When you have kidney stones either in the kidney or in the ureter along its length going towards the bladder, it can cause blockage of urine, then back pressure up to the kidney and then pain as the urine can’t pass. This is referred to as renal colic, and the pain is described as equivalent to giving birth.
One method of treating kidney stones as noninvasively as possible, is through ESWL. In this procedure, you will attend the VGH Acute Stone Center in the Radiology Department of VGH (Ground floor, Jim Pattison Pavilion) where the lithotriptor is housed. There you will be given mild sedation, and lie down on a special bed that has both an X ray machine built in, as well as a shockwave generator. The stone is targeted by the Urologist using the X rays, and who then starts the shocks.
The shocks generated by the machine are sound waves that are focused on the stone inside the body. The repeated crashing of the sound waves into the stone cause it to fragment into smaller and smaller pieces, eventually turning into small particles that can be passed easily in the urine.
Of course, anything that is strong enough to break a stone inside your body also has the risk for damaging other structures as well, and bleeding is one of the main risks associated with this treatment modality. Although the risk is low, it is not zero. Patients on blood thinners other than aspirin will require stoppage of the medications or selection of alternative procedure for their stones.
This is a day procedure, so you will be admitted, have the procedure, and then be discharged on the same day but cannot drive yourself home as you will have had a bit of an anesthetic. Therefore, ensure that you have someone available to pick you up afterwards.
Several weeks after the procedure, your Urologist will schedule you for followup X ray and Ultrasound exams to determine if there are any residual stone fragments left. If so, and if they are of appropriate size, you may be eligible for re-treatment. Most patients will select ESWL as the first line of treatment for stones as it is so noninvasive, however since some estimates place ESWL at only 70% stone free rates following a single treatment, repeated treatments can be required. If several attempts with ESWL have failed to clear the stone(s), then ureteroscopy is usually the recommended next step.