Kidney Stones | Treatment
Fortunately, about 90% of stones 4 mm or smaller pass spontaneously. A stone that is likely to pass through based on its size is given four weeks in most cases to pass before further intervention is planned. Various measures may be suggested to encourage the passage of a stone including increased hydration, medications to treat infection and reduce any pain, and diuretics to increase urine flow and prevent further stone formation. Waiting for a stone to pass is bypassed in special situations such as if the patient has only one working kidney or an infection is present in a kidney blocked by a stone.
Approximately 99% of stones larger than 6 mm in size need some form of intervention. The most common form of management is for pain, and will depend on your physician. Additionally, a class of drugs called alpha adrenergic blockers, which include Flomax, Terazosin, Doxazosin and Uroxatral, may be prescribed. These drugs reduce the muscular tone of the ureter, and can increase the rate of spontaneous passage of stones significantly. Depending on the type of stone and the underlying situation promoting its formation, you may be prescribed certain medications to correct the conditions that led to the formation of your stone.
Most kidney stones do not require surgery. Reasons to have surgical management for your kidney stone are as follows: the stone has not passed after a reasonable time and is causing constant pain, is too large to pass on its own or is causing significant blockage of urine flow. Other indications for surgery are if there is an infection caused by the stone, damage to kidney tissue or constant bleeding, and if the stone is consistently growing in size.
Over the past two decades, minimally invasive techniques have been developed and improved upon to eliminate kidney stones, greatly reducing the need for open surgery and long recovery times. Several of these techniques are described briefly here, and some have links to more detailed pages.
- Ureteral stent: A small tube is placed to run between the bladder and inside of the kidney (the stent), which immediately allows urine to drain around a stone. Stents are useful to allow an infection to go away or keep the ureters open while a fragmented stone passes through. They also are useful because they stretch the ureters gently to allow ureteroscopy, discussed below. Stents are easily removed in an office visit.
- Extracorporeal Shock Wave Lithotripsy (ESWL): If a stone is found in the kidney that is too large to pass spontaneously, it can be broken apart before it passes into the ureter and causes any problems. With ESWL, ultrasound is used to pinpoint the location of the stone, and then energy waves are targeted specifically to the stone to break it apart so that the pieces can pass spontaneously through your system. This procedure is non-invasive and is the most commonly used procedure for treating stones that cannot be passed. There are other forms of lithotripsy, including holmium laser lithotripsy, that are discussed in greater detail here on the lithotripsy page.
- Ureteroscopy: This method of kidney stone treatment is explained in greater detail here on the ureteroscopy page. Briefly, ureteroscopy is highly effective for removing stones in the lower ureters, close to the bladder. A long, thin telescope (the ureteroscope) is passed through your urethra, through your bladder and up into the ureter to the point where the stone is stuck. One the scope is inserted, the stone can be either removed using a basket, or fragmented using some sort of laser, ultrasound or mechanical energy.
- Percutaneous Nephrolithotomy: For stones in the kidney that are resistant to ESWL or have a certain size or shape, this procedure is often chosen to remove stones. In this procedure, another thin and long telescope called a nephroscope is passed through an incision made in your back and guided to your kidney. The stone is then pulled out or fragmented in a manner similar to used with ureteroscopy. This procedure requires general anesthesia.
- Open surgery: If a stone is unsuitable for treatment with any other method, or if other methods fail to remove the stone, then your urologist will recommend open surgery to directly remove the stone.
Each of these procedures has specific indications for use, and carry their own risks and benefits. Your Northwoods urologist will clearly and thoroughly explain all of these before making a recommendation for treatment. Some of the factors that will be discussed and weighed with you are:
- Stone location
- Number of and sizes of stones
- Stone composition
- How long the stone has been present and causing symptoms
- Pain caused by the stone
- Whether or not there is infection
- Patient expectation and desire
- Patient anatomy