Ureteral Stones 0.3 cm to 0.8 cm in Size: How We Break and Remove Small Stones in the Ureter at New York Urology Specialists
Dr. Alex Shteynshlyuger is a board certified urologist in NYC who specializes in treating men and women with kidney stones and ureteral stones.
Treatment of 3mm – 8 mm Ureteral Stones
Ureteral stones can block and cause obstruction in any part of the ureter (upper, middle, or lower). When kidney stones block urine from freely flowing from the kidney down the ureter and into the bladder, accumulation of urine in the kidney leads to dilatation of the kidney, called hydronephrosis. Blockage of the ureter by ureteral stones also leads increased pressure within the kidney which in turn causes pain in the back, flank or lower abdomen. Pain and stones can also lead to nausea, vomiting, decreased appetite; sometimes blood in the urine can occur.
How are 0.5 cm to 0.8 cm Ureteral Stones Treated and Removed?
Most but not all patients are able to pass stones smaller than 3 mm-4 mm, whether they are in the proximal ureter, mid-ureter or distal ureter. Similarly most patients are able to pass stones that are up to 7mm or 8 mm in size especially if they are in the distal ureter (up to 85%). The chances of passing stones that are 7-8 mm or larger are not as good if they are in the proximal ureter or at the UPJ (around 50-60%).
If intervention is necessary, either ESWL lithotripsy or ureteroscopy with laser lithotripsy are effective for ureteral stones that are smaller than 0.7 cm or 0.8 cm.
Passing Ureteral Stones is an Option for Many Patients
For stones that are smaller than 5 mm in particular, but also for stones smaller than 8 mm, it is usually possible to try to pass them spontaneously with medical expulsive therapy (MET). This is a conservative approach to treatment and uses fluids, pain medication, and ureteral relaxants such as Flomax to help the patient pass the stone spontaneously. Urologists will typically allow 4-6 weeks of MET to see if a patient can pass the stone on their own. A patient may experience mild pain when the stone passes or the stone may pass without the patient being aware. If possibly, patient should use a ‘stone strainer’ to catch the stone.
Trying to pass a stone is reasonable if patient has no signs of infection (fever, chills, etc), pain is mild or can be well controlled with pain medications and there is no severe nausea or vomiting.
If the patient is experiencing severe or recurrent pain or has nausea and vomiting and cannot tolerate a diet, then an early intervention may be reasonable. Typically in an urgent situation a ureteral stent can be placed or patient can undergo either shock-wave or ureteroscopy with Holmium laser as long as there are no signs of infection. If there are signs of infection in a patient with ureteral of kidney stones, immediate treatment usually with ureteral stent insertion is necessary to prevent life-threatening infection and sepsis.
It should be noted that observation is a reasonable option only if the patient is infection-free. If infection is present, this must be treated with antibiotics and an urgent intervention with a ureteral stent insertion or nephrostomy is performed. It is usually necessary to insert a stent in the ureter to keep it open and to decompress the kidney while the infection is being treated. If the ureter is blocked, infection may be difficult or impossible to cure without unblocking it.
If intervention is necessary, be either ESWL or ureteroscopy with laser lithotripsy are effective for ureteral stones that are smaller than 0.7 cm or 0.8 cm.
Shockwave Lithotripsy for Small Ureteral Stones
Shockwave lithotripsy (ESWL) is an effective and minimally invasive treatment option to break ureteral stones. ESWL is a same day procedure and most patients are able to return to work and regular activities the next day. Shockwave lithotripsy is usually used for stones larger than 5-6 mm in the ureter as smaller stones usually cannot be seen well on X-rays in the ureter. About 50% of ureteral stones are visible on X-rays and can be treated with ESWL.
Shock-wave lithotripsy is not an option for women of reproduction age with lower ureter stones as this procedure is not safe to perform near the ovaries. In general for lower ureteral stones in men and women, and in particular for UVJ stones, ureteroscopy is the preferred procedure.
Ureteroscopy with Holmium Laser to Break and Remove Small and Medium-Sized Ureteral Stones
ESWL is less invasive compared to ureteroscopy and is a reasonable option for smaller stones such as a 6 mm or 7 mm upper ureteral stone. However, ureteroscopy gives the urologist direct access to the stone and has a higher success rate in rendering patients stone free.
Ureteroscopy can be performed on stones that are not visible on X-rays and thus cannot be treated with ESWL. Ureteroscopy can be performed on any stone in any location within the ureter regardless of stone size or stone location. Typically, it is a same day procedure which means the patient is able to go home the same day. Most patients are able to return to regular activities within 1-2 days.
An additional benefit of ureteroscopy is that a stone sample can be retrieved during ureteroscopy to determine its biochemical composition. This can help direct future preventative treatment. A ureteral stent is usually left in place for a few days to a few weeks depending on complexity of the procedure after ureteroscopy. Ureteral stenting is usually not necessary after shock-wave lithotripsy. But if a patient had a ureteral stent placed before ESWL, it is typically removed about 2 weeks after ESWL or once the patient is confirmed to be stone-free
For smaller stones in the ureter that are less than 8 mm in size, both ESWL and ureteroscopy are reasonable options but for technical or medical reasons not all patients are candidates for shockwave lithotripsy. Both procedures are same-day outpatient interventions performed under anesthesia and the recovery from both procedures usually takes 1-2 days.
Dr. Alex Shteynshlyuger is a board certified urologist in NYC who specializes in treating men and women with kidney stones and ureteral stones. He has treated hundreds of men and women with large kidney stones.